BIOLOGICAL BASIS OF BEHAVIOR
Psychology 321
Spring, 2005 HGH 225
Dr. John M. Morgan MWF, 8am to 9:00
Hypothalamic lesion from perspective of neurologist and
neurosurgeon
By: Katrin Beene
The hypothalamus is a substructure of the diencephalon and acts
as one of the most significant control centers of the brain. It
is located inferior to the thalamus, encapsulates the ventral
portion of the third ventricle, and lies just superior to the
pituitary gland, which it has direct regulatory control over
(Gunderson, 1996). Neurosecretory neurons in the hypothalamus
secrete releasing and inhibiting hormones which are carried to
the anterior pituitary where they exert their effects via
hypothalamic-hypophyseal portal veins. Included in the many
functions of the hypothalamus are regulation of food and water
intake, autonomic function, emotions, body temperature, motor
functions, and circadian sleep-wake cycles (Kalat, 2004).
Hormones secreted by the hypothalamus include Thyrotropin-
releasing hormone, Gonadotropin-releasing hormone, Growth-
releasing hormone, Corticotropin-releasing hormone,
Somatostatin, and Dopamine (Klaus,n.d.).
Medically, a lesion is a term referring to abnormal tissue
in the body that can be caused by many factors including
disease, trauma, infection, or neoplasm which is an abnormal
growth of tissue, such as a tumor (Healthopedia.com, n.d.). For
the purpose of this paper tumor and lesion will be used
interchangeably.
As a neurologist I am a medical doctor with specialized
training in diagnosing, treating, and managing disorders of the
brain and nervous system, including diagnosis of brain tumors.
As a professional I act as the primary care provider for
patients with chronic neurological problems and as a consultant
to other physicians who have clients suspected of having a
condition involving the nervous system (Life NPH, n.d.). A
neurological examination allows me to effectively diagnose the
condition of the patient and suggest appropriate treatment
options. I first review the patient's health history with
special attention to the current condition. A patient suspected
of having a disorder of the nervous system will be subjected to
a general neurological examination which includes testing of eye
movement and pupil reaction, hearing, reflexes, balance and
coordination, sense of touch, sense of smell, facial muscle
functioning, gag reflex, head movement, mental status, abstract
thinking, and memory (Malhi, 2000).
A full neurological examination is generally administered,
despite any preconceived opinions of a patient’s potential
ailment, in order to illustrate the condition as clearly as
possible and rule out any alternative diagnosis. An examination
takes 90 minutes or more in most cases and consists of a battery
of tests. A neurological exam tests for a client’s level of
function of the area of the nervous system involved in a given
task, thus each segment of the exam must cover a scope from easy
to difficult to accommodate for naturally occurring differences
between individuals (Neuroexam.com, n.d.). For the purpose of
this paper it is not realistic or necessary to describe each
step of the exam but I will give a few examples to demonstrate
the types of tests involved.
The optic nerve (cranial nerve II) should be tested for
function of visual fields, visual acuity, and fundoscopy. To
test visual fields I ask the patient to shut their left eye and
look straight into my right eye. I introduce a pinhead (white
for peripheral field testing and red for central field) into the
patient’s field of vision midway between us and from several
different directions. Each time, the patient reports its
appearance as soon as it is detected. Visual acuity is tested by
having the patient read from eye charts from varying distances
for near and far vision. Fundoscopy is the examination of the
retina which is best done in a dark room so that the pupils are
better able to dilate. The patient stares at a fixed point in
the distance and I approach each eye in turn with an
opthalmoscope from an angle of approximately 15 degrees
(Malhi,2000).
Testing of the noncortical sensory system involves testing
for responses to tactile stimulation, temperature, and
vibration. To test light touch I have the patient close their
eyes and gently touch their skin in various areas with a piece
of cotton and have them report whether they feel the touch or
not (Neuroexam.com, n.d.). To test pain I once again have the
patient close their eyes and randomly apply a blunt or sharp
stimulus in random patterns, then have the patient report the
nature of the stimulus. To test temperature I apply a hot or
cold tube of water to the patient’s skin. Vibration is tested by
pressing a quivering tuning fork against a bony prominence, such
as the patella, and having the client report to what extent they
feel a vibration (Malhi, 2000).
In some cases, lesions of the hypothalamus may present no
overt symptoms but generally, a variety of neurological,
hormonal, and ophthalmologic symptoms cause a person to seek
help and lead the clinician to an accurate diagnosis.
Hypothalamic tumors that extend into the area of the pituitary
may lead to endocrine, visual, and neurological symptoms
comparable to those observed in patients with pituitary tumors.
The triad of symptoms that present the clearest indication of a
hypothalamic tumor are hypogonadism, central diabetes insipidus,
and visual disturbances. Hypogonadism is a deficiency of sex
hormone secretions from the gonads. Central diabetes insipidus
is a condition where the kidneys are unable to conserve water
during their filtering process due to abnormal secretion and
storage of ADH (Antidiuretic hormone or vasopressin) by the
hypothalamus and pituitary gland. Visual disturbances occur as a
result of the tumor compressing an area of the optic tract or
chiasma (Klaus,n.d.).
Other symptoms of a hypothalamic lesion include weight
loss or gain, paleness, excessive sweating, tremor or shakiness,
irritability, involuntary eye movements, euphoria, headaches
that tend to be worse during the morning, and, in children,
failure to thrive, which is a lack of normal growth (Cook,
1996).
The ventromedial region of the hypothalamus is responsible
for triggering satiety, and thus cessation of eating and
drinking behavior, and the lateral region of the hypothalamus is
involved with the initiation of eating and drinking.
Hypothalamic lesions, depending on their exact location, can
cause abnormal control of satiety which may lead to hyperphagia
(gross overeating) and eventual obesity or, in the opposite
direction, to cachexia (loss of body fat and appetite) (Klaus,
n.d.).
If the physical portion of the neurological examination
indicates the likelihood of a brain tumor I will then recommend
that the patient undergo further diagnostic testing involving
brain scans and/or a lumbar puncture. Brain scans are able to
provide an image of the brain that includes regions behind bone.
Common diagnostic scans for brain lesions include CAT and MRI
scans.
Before a CAT scan the patient is injected with a dye-like
solution that provides the x-ray device and computer a clearer
contrast between healthy and abnormal tissue. The patient is
placed on a flat surface that slides into a doughnut-shaped
opening (American Brain Tumor Association, n.d.). The scanner
circles the patient’s head, creating images of the brain based
on penetrating x-rays. The imaging portion of the procedure
should only take 10-15 minutes (Malhi, 2000).
The MRI is more sensitive than a CAT scan in detecting
brain lesions as it provides a higher resolution but it also
tends to be more expensive and is contraindicated for people
with any type of metal implant in their body (Malhi, 2000). The
patient lies on a table that slides inside of the tunnel-shaped
MRI. No x-rays are used in this procedure but instead a magnetic
field affects the movement of the atoms in the brain. Antennas
detect signals from the atoms and relay information to a
computer which pieces together an image of the brain (American
Brain Tumor Association, n.d.)
Brain scans can give important information about the
nature, location, and stage of a person’s lesion. They play a
vital role in planning and implementing treatment.
As a neurosurgeon I am trained in the operative and non-
operative diagnosis, management, prevention, and treatment of
neurological disorders. Incorporating diagnostic information and
opinions from other physicians and neurological specialists,
such as primary physicians, neurologists, and
nueropsychologists, I determine the most effective plan of
treatment for the given patient (Life NPH, n.d.).
Surgery is the preferred treatment for tumors and lesions
located within the brain but some areas of the brain may be
inoperable due to location or quality of the lesion. Among the
brain areas that are often deemed inoperable are the brain stem,
motor area, thalamus, and some areas of gray matter (University
of Chicago Department of Surgery, n.d.).
If a lesion is deemed surgically accessible and further
diagnostic information would be helpful in planning treatment,
then I will generally perform a biopsy A biopsy is a surgical
procedure in which a small quantity of the tumor is removed for
examination by a neuropathologist. For those areas of the brain
not easily accessible via an open biopsy, stereotaxic biopsy is
often employed. This process entails drilling a small hole in
the skull and inserting a narrow, hollow needle which is guided
via sterotaxic instrumentation to the location of the tumor.
Tumor tissue is then removed from the center of the needle and
examined by a neuropathologist to arrive at an accurate
diagnosis and classification of the lesion (American Brain Tumor
Association, n.d.).
There are many different types of lesions that may occur
at the site of the hypothalamus or that may affect it
indirectly. Hypothalamic lesions can occur at any age but many
are developmental and present themselves during childhood. Some
classifications of hypothalamic lesions include
craniopharyngioma, glioma, germinoma, chordoma, and hamartoma.
Craniopharyngiomas are benign but their growth often infiltrates
and causes adverse effects upon other brain structures
(Klaus,n.d.). Most hypothalamic tumors in children are gliomas
which originate from the supportive glial cells of the brain.
The presence of certain genetic syndromes, such as
neurofibramotosis, increases the risk of developing gliomas
(Gunderson, 1982). Germinomas develop from germ cells and are
most frequently observed in adult males. In younger patients
germinomas often present themselves through precocious puberty,
a condition in which the onset of puberty is significantly
premature, often before the age of eight (Klaus,n.d).
Some types of hypothalamic lesions are inoperable due to
the nature, specific location, and grade of the tumor.
Fortuantely there are some, most craniopharyngiomas for example,
that are surgically accessible. When determining whether surgery
is a viable option for a given patient I have to take into
consideration the exact location of the offending lesion, the
surrounding structures that may be affected by surgery, the age
and health of the patient, and whether alternative therapies may
provide a more effective or safer treatment option (American
Brain Tumor Association, n.d.).
As mentioned previously, surgery is the preferred option
for the most effectual treatment of brain tumors. The goal of
tumor resectioning is to remove as much of the tumor as
possible. A patient who will be undergoing brain surgery is
generally admitted to the hospital the day before surgery.
Before the day of surgery I will meet with a patient to answer
questions and discuss the surgical procedure, possible risks and
benefits, and alternative treatments. Generally surgical
resection of a tumor is executed by means of a craniotomy. A
craniotomy entails the removal of a piece of skull bone which is
replaced and secured back into place after surgery (American
Brain Tumor Association, n.d.).The patient usually lies on their
back and a general anesthesia, which causes the patient to
remain unconscious during the operation, is administered prior
to the beginning of the procedure. The area where I will be
making the incision is shaved and cleaned. I then make an
incision in the scalp and use a surgical saw to remove a portion
of bone over the brain area containing the tumor. Carefully, I
slice through the membranes surrounding the brain and use an
assortment of specialized tools to remove the abnormal growth
from the brain (The University of Chicago Department of Surgery,
n.d.). Some of the tools I might employ include a surgical
laser, an operating microscope, ultrasonic aspirator, and
stereotactic instrumentation (American Brain Tumor Association,
n.d.). When I feel that sufficient removal has been completed, I
will replace the membranes and skull bone and stitch the skin
back together.
Brain surgery can be a highly effective treatment but it
also poses the threat of serious complications such internal
bleeding, infection, brain damage, and death (The University of
Chicago Department of Surgery, n.d.). If removal of the tumor
was successful then the patient can expect a positive prognosis
regarding recovery rate and expected mortality.
Radiation and chemotherapy may be used as secondary
therapies if there is a question to the success of the surgery.
They may also be used as primary therapies if brain surgery is
too risky or not considered necessary. Radiation is the use of
high energy x-rays to destroy abnormal cells or to alter their
metabolism and thus alter their ability to function.
Chemotherapy involves the use of cytotoxic drugs to destroy
cancerous cells by interfering with their ability to reproduce
themselves (National cancer Institute, n.d.).
American Brain Tumor Association.(n.d.). Fifth Edition A Primer
of Brain Tumors: A Patient’s Reference Manual.
http://neurosurgery.mgh.harvard.edu/abta/primer.htm . (Retrieved
April 19, 2005).
Bast, R.C. (Ed), Kufe, D.W. (Ed), Holland J.F. (Ed), & Frei,E.
(Ed).(2003). Cancer Medicine, 6th edition. Ontario: B.C. Decker
Cook, A.R. (Ed). (1996). The New Cancer Sourcebook. Detroit:
Omniographics.
Gunderson, C. H.( 1982). Quick Reference to Clinical Neurology.
Philadelphia: J.B. Lippincott
Healthopedia.com. www.healthopedia.com (Retrieved April 19,
2005).
Klaus.W. (n.d.) Endotext.com. Pituitary-Hypothalamic Tumor
Syndromes: Adults www.endotext.org (Retrieved April 22, 2005).
Life NPH.(n.d.). http://www.allaboutnph.com (Retrieved April
21,2005)
Malhi, G.S. (2000). Neurology for Psychiatrists. London: Martin
Dunitz Ltd.
National Cancer Institute. www.nci.nih.gov (Retrieved May
2,2005)
Neuroexam.com. (n.d.). www.neuroexam.com (Retrieved May 1,
2005).
The University of Chicago Department of Surgery. (n.d.)
http://surgery.uchicago.edu/neurosurgery/brainsurgery.cfm
(Retrieved May 2, 2005)
Behaviors Caused by Hypothalamic and Thalamic Lesions from the
Perspective of a Neuropsychologist
By: Hannah Rich
In the field of neuropsychology, the area in the brain that
includes the hypothalamus, the thalamus, and the subthalamus is
referred to as the subcortex diencephalon (Kalat 2004). In the
following section, lesions to these specific areas will be
discussed. The results of the lesions will be addressed from the
perspective of a neuropsychologist. Neuropsychological
assessment refers to the objective evaluation of the cognitive,
linguistic, perceptual, and psychomotor performances of a person
with the aim of relating the status of his/her performances to
the structural and functional condition of his/her brain
(Steinhauer, Gruzelier, & Zubin 1991). Neuropsychological
assessment can be approached from an experimental method in
which the researcher has greater control of the variables
affecting the situation but, generalization is more difficult
and human subjects cannot be used in studies (Finger 1978). A
clinical method is also used and, although this method does not
experience the benefit of complete control, brain-behavior
relationships are much easier to study because human subjects
can be used in this method (Finger 1978). Both methods are
usually combined to produce the most efficient and helpful
information for the patient. The most prominent
neuropsychological tests include the Wechsler Adult Intelligence
Scale, the Halstead-Reitan battery, and the Wechsler Memory
Scale (Steinhauer et. al. 1991). These tests provide the
opportunity to analyze the components of performance and then
identify probable disabilities that would explain the defective
performance (Steinhauer, et. al. 1991). The main issue that will
be examined in this section will be behavioral effects of
lesions to specific parts of the hypothalamus and the thalamus.
The hypothalamus is located near the base of the brain and
is ventral to the thalamus (Dimond 1978, Kalat 2004). The
hypothalamus is part of the limbic system and is responsible for
motivational behaviors including emotion, eating, drinking,
sexual activity, anxiety and aggression (Kalat 2004, Dimond
1978, Isaacson 1982, Beaumont 1983). The hypothalamus has
widespread connections to the rest of the forebrain and also to
the midbrain (Kalat 2004). The hypothalamus contains a number of
distinct nuclei including the lateral nucleus which controls the
initiation of eating and drinking, the ventromedial nucleus
which controls the stopping of eating and drinking, the
paraventricular nucleus which limits meal size, the supraoptic
nucleus which controls the secretion of vasopressin, the
suprachiasmic nucleus which constitutes the biological clock,
and the POA/AH (preoptic area and the anterior hypothalamus)
which controls body temperature (Kalat 2004, Isaacson 1982,
Dimond 1978). The hypothalamus is also responsible for
regulating the release of hormones which contributes to the
management of many various bodily systems.
The hypothalamus conveys messages to both the anterior and
posterior pituitary gland through nerves and hypothalamic
hormones which results in an altering degree of hormones that
are released by the pituitary gland (Kalat 2004). The pituitary
gland is composed of two parts, the posterior and the anterior.
The posterior part of the pituitary gland is comprised of neural
tissue and is actually considered to be an extension of the
hypothalamus (Kalat 2004). The hypothalamus produces two of its
own hormones. These hormones are called vasopressin and oxytocin
(Kalat 2004, Isaacson 1982). Vasopressin is a hormone that
raises blood pressure and enables the kidneys to reabsorb water
(Kalat 2004). Oxytocin is a hormone as well as a
neurotransmitter that is important for sexual and parental
behaviors (Kalat 2004). When these hormones are released from
the hypothalamus they travel to the posterior pituitary gland
which then releases various hormones into the blood. On the
other hand, the anterior pituitary gland is made up of glandular
tissue and receives releasing hormones that are secreted by the
hypothalamus (Kalat 2004). These releasing hormones stimulate or
inhibit the release of hormones by the anterior pituitary gland.
Some of these hormones include the thyroid-stimulating hormone
(TSH), prolactin, the growth hormone, follicle-stimulating
hormones (FSH) and hormones that control the secretions of the
adrenal cortex, the secretions of the thyroid gland, the
secretions of the mammary glands, the secretions of the gonads
and finally hormones that promote growth throughout the body
(Kalat 2004). When the hypothalamus or the pituitary gland is
damaged the results can show up in abnormal behavior. The
behaviors that can be affected include motivational behaviors of
eating, drinking, temperature regulation, sexual behavior,
and/or activity level (Kalat 2004, Dimond 1978, Isaacson 1982).
The hypothalamus is also partly responsible for levels of
bodily arousal. According to Kalat, the hypothalamus contains
cells that have the potential to produce excitatory or
inhibitory effects (2004). One of the neurotransmitters that the
hypothalamus produces is GABA. GABA is an inhibitory transmitter
that is involved in decreased arousal. A lesion to the GABA-
releasing cells of the hypothalamus results in a state of
prolonged wakefulness, and/or an increased state of arousal
(Kalat 2004).
Body temperature is also controlled by the hypothalamus.
The specific area that is responsible for the physiological
changes that defend body temperature (sweating, shivering, etc.)
is called the POA/AH, or the preoptic area and the anterior
hypothalamus (Kalat 2004). Damage to the POA/AH impairs a
mammal’s ability to regulate their temperature. The mammal tends
to rely on behavioral mechanisms of regulation instead of
physiological efforts (Kalat 2004). According to Dimond, when
the temperature regulation area of the hypothalamus is damaged
abnormal behaviors of panting, sweating, and shivering can be
observed (1978).
One of the most important functions of the hypothalamus is
to regulate the behaviors of eating and drinking. This includes
both the initiation and satiation of eating and drinking. The
lateral nucleus of the hypothalamus is responsible for the
initiation of eating and drinking (Kalat 2004, Isaacson 1982).
It does this by controlling insulin secretions, taste
responsiveness, ingestion, swallowing, and digestive secretions
(Kalat 2004). Damage to the lateral nucleus of the hypothalamus
results in refusal of food (aphagia) and water (adipsia) even if
it is hungry and/or thirsty (Isaacson 1982, Kalat 2004). Animals
that recover from lateral hypothalamic damage do not return to
the same body weight as normal animals despite normal levels of
food intake (Isaacson 1982). In conclusion a lesion to the
lateral nucleus of the hypothalamus results in undereating,
weight loss, and low insulin levels (Kalat 2004, Isaacson 1982).
The ventromedial nucleus of the hypothalamus is responsible
for the stopping or satiation of eating and drinking behaviors
(Kalat 2004). When there is a lesion to this part of the
hypothalamus the animal doesn’t have the ability to stop eating
(hyperaphagia). According to Isaacson animals with lesions to
the ventromedial hypothalamus have permanent hyperaphagia and
obesity (1982). Some of the behaviors that accompany a lesion to
the ventromedial hypothalamus include an increase in appetite,
finicky eating, a higher frequency of normal size meals, an
increase in stomach motility, an increase in digestive
secretions, an increase in insulin production, and an increase
in fat stores (Kalat 2004, Isaacson 1982). In order for these
effects to occur the lesion must extend outside the ventromedial
nucleus and invade the nearby medial hypothalamic cells (Kalat
2004). Another area that is also involved in the limiting of
eating behavior is the paraventricular nucleus of the
hypothalamus. When the paraventricular nucleus is functioning
normally it provides the animal with the ability to determine
what an appropriate meal size is for their physiological needs
(Kalat 2004). When the paraventricular nucleus is damaged, the
animal overeats but the reason is different from that of an
animal that overeats because they have a lesion to the
ventromedial nucleus. When the paraventricular nucleus is
damaged the animal eats larger meals rather than eating more
frequently. This is because the paraventricular nucleus is
insensitive to the signals from periphery systems indicating the
end of a meal (Kalat 2004). Eventually after the animal has
doubled or, in some cases tripled their body weight, other
physiological mechanisms will step in and stop the weight gain.
The lateral preoptic area of the hypothalamus controls
drinking (Kalat 2004). Thirst can be divided into two
categories, osmotic thirst and hypovolemic thirst. Osmotic
thirst occurs when there is a higher concentration of solutes on
the outside of the cell than there is on the inside, this
results in osmotic pressure which draws the water out of the
cells causing dehydration and thirst (Kalat 2004). A lesion to
the lateral preoptic area impairs osmotic thirst by disrupting
the systems that detect when the concentration of solutes is not
in a state of equilibrium (Kalat 2004). Hypovolemic thirst
happens when blood volume drops sharply. This may be because of
severe bleeding, diarrhea or extreme sweating. During
hypovolemic thirst the animal needs to replenish lost salts and
solutes in addition to water (Kalat 2004).
Another important aspect of the hypothalamus is its role in
sexual differentiation. The sexually dimorphic nucleus is
located within the anterior hypothalamus and contributes to the
control of sexual behavior and the development of sexual
characteristics (Kalat 2004, Dimond 1978). Critical or sensitive
periods are important in determining which hormone will have
long-term effects on the hypothalamus. If a fetus is exposed to
large amounts of testosterone in the critical period then the
hypothalamic cells will go through a process of masculinization
and will develop receptors for androgens (male hormones). If
there is an absence of androgens during the critical period then
the female hormones will cause the hypothalamic cells to
feminize and androgen receptors will not develop. Parts of the
female hypothalamus generate a cyclic pattern of hormones that
are released which is known as the menstrual cycle (Kalat 2004).
The effects of the sexual hormones on the hypothalamus result in
sexually dimorphic behavior later in life. These behaviors
include but are not limited to sexual/mating behavior.
The thalamus is a structure located in the center of the
forebrain and is the main source of sensory input to the
cerebral cortex (Kalat 2004, Beaumont 1983). Most of the sensory
information goes first to the thalamus which then processes it
and then sends the output to the cerebral cortex. The thalamus
is also involved in arousal. The pontomesencephalon (a region of
the reticular formation that contributes to cortical arousal)
sends axons down into the thalamus and releases acetylcholine
and glutamate which results in an excitatory effect (Kalat
2004). The thalamus then relays this arousal to widespread areas
of the cortex. The thalamus governs sensation and movement and
is the control center for the general underlying motor functions
(Beaumont 1983).
Damage to areas of the thalamus produce a variety of
behaviors including: resting tremors, chorea (rapid, jerky,
involuntary movements), dystonia (uncontrolled movement),
Parkinsonism (rigidity of movement, shuffling gait, loss of
associated movements, loss of emotion and expression, and
tremors), and disturbances in consciousness (e.g. verbal
performance, facial recognition, facial matching, etc.)(Beaumont
1983).
The hypothalamus and the thalamus are very integral parts
of the brain and by using neuropsychological assessments
scientists and doctors can work together to try and help
individuals who have damage to these areas.
Works Cited
Beaumont, J.G. (1983). Introduction to Neuropsychology. New
York: Guilford Press.
Finger, S. (1978). The interplay of experimental and
clinical approaches in brain lesion research. In Benton, A. L.
(ed.) (2000). Exploring the History of Neuropsychology. Oxford:
Oxford University Press.
Isaacson, R.L. (1982). The Limbic System. New York: Plenum
Press.
Kalat, J.W. (2004). Biological Psychology. Wadsworth,
United States.
Steinhauer, S.R., Gruzelier, J.H., and Zubin, J. (1991).
Basic approaches to neuropsychological assessment. In Benton, A.
L. (ed.) (2000). Exploring the History of Neuropsychology.
Oxford: Oxford University Press.
Tumors or Lesions to the Hypothalamus
Patient him/herself
By Nicole Musone
The Hypothalamus is a small area near the base of the brain
just ventral to the thalamus. It has widespread connections
with the rest of the forebrain and the midbrain. Partly through
nerves and partly through hypothalamic hormones, the
hypothalamus conveys messages to the pituitary gland, altering
its release of hormones (Kalat, 2003). Any type of damage to a
hypothalamic nucleus, such as tumors or lesions, may lead to
abnormalities in one or more motivated behaviors, such as
feeding, drinking, temperature regulation, sexual behavior,
fighting, or activity level.
The exact cause of hypothalamic tumors is not known. It is
likely that they result from a combination of genetic and
environmental factors. In children, most hypothalamic tumors
are gliomas. Gliomas are a common type of brain tumor that
results from the abnormal growth of glial cells, which are a
type of cells that support nerve cells. Gliomas can occur at
any age but they are often more aggressive in adults than
children. In adults, tumors in the hypothalamus are more likely
to be metastatic (resulting form the spread of cancer form
another organ to the hypothalamus) than they are when they occur
in children.
Peter Heage, of Colorado, was diagnosed with a hypothalamic
brain tumor. He said that he was having headaches too often,
and they were different from most headaches he had in the past.
He would forget things, and then forget more often. He said he
had a vague feeling that something just wasn’t right. One day
he had a seizure while he was at work. After seeing his
physician, he told him that he had some of the common symptoms
of a brain tumor.
Brain tumors have a variety of symptoms ranging from
headache to stroke. Seizures may be the initial manifestation
of a brain tumor, and eventually as many as 30% of patients with
brain tumors will develop seizures. Gradual loss of movement or
sensation in an arm or leg may occur. Unsteadiness or
imbalance, and double vision may occur, especially if it is
associated with headache. Loss of vision in one or both eyes
could result with a brain tumor, depending on the exact location
of the tumor. An eating disorder for a child, and loss of
appetite for an adult could be one of several possible symptoms.
Hearing loss and speech difficulty of gradual onset may also be
symptoms. Patients with tumors of the hypothalamus region
specifically, can cause a range of symptoms; Cachexia (loss of
body fat and appetite), hyperactivity, euphoric “high”
sensations, headaches, and failure to thrive (lack of normal
growth in children), which are most frequently seen in children
whose tumors affect the anterior (front) portion of the
hypothalamus. Some of these hypothalamic tumors may extend to
the visual pathways, which can cause loss of the person’s
vision. If the tumors block the flow of spinal fluid, patient
may experience headaches and sleepiness as a result from
hydrocephalus (collection of fluid in the brain). Some of these
patients have seizures as a result from the brain tumor itself.
If a person is experiencing any of these symptoms, they
should see their physician promptly. If the patient’s doctor
identifies an abnormal development during a regular checkup,
they may perform a neurological exam, including testing of
visual function, which may provide more information about how
severe the vision is affected and possibly blood tests, for
hormone imbalances. Depending on the results of the
examination and blood tests, a CT scan or MRI scan can determine
the presence of hypothalamic tumors.
A CT scan is a procedure that makes a series of detailed
pictures of areas inside the body, taken from different angles.
The pictures are made by a computer lined to an x-ray machine.
A dye may be injected into a vein or swallowed to help the
tissues show up more clearly. In rare cases some patients
report a temporary headache, but otherwise it has no known side
effects (National Brain Tumor Foundation). An MRI, magnetic
resonance imaging, is a procedure that uses a magnet, radio
waves, and a computer to make a series of detailed pictures of
the brain. A substance called gadolinium is injected into the
patient through a vein. The gadolinium collects around the
cancer cells so they show up brighter in the picture. A PET,
Positron Emission Tomography, is a relatively new test that
measure cellular activity. An injection of radioactive glucose
dye is given to the patient and then a scan is made; since
malignant tumor cells metabolize glucose more quickly than
healthy cells, they also take up more of the radioactive marker
(National Brain Tumor Foundation). This technique can be
especially useful in distinguishing dead tissue masses from
active tumor cells, though this test is not always 100%
accurate. A biopsy can be done by removing part of the
patient’s skull and using a needle to remove a sample of the
brain tissue. After the biopsy the doctor can determine if the
patient has any cancer cells, and if so, they can find out the
grade of the tumor. The grade of a tumor refers to how abnormal
the cancer cells look and how quickly the tumor is likely to
grow and spread. A grade I tumor grows slowly, and rarely
spreads to nearby tissues and may be possible to remove the
entire tumor by surgery. Grade II tumors are also slow growing,
but may spread into nearby tissue, and become a higher-grade
tumor. Grade III tumors grow quickly, and are likely to spread
into nearby tissue. Grade IV tumors grow very aggressively, and
is difficult to treat successfully. Visual field testing may
provide more information about severely the vision is affected
and can help determine if the condition is improving or
worsening. Prognosis of this type of tumor depends on several
factors: type of tumor (i.e., glioma or other type), grade of
tumor, size of tumor, age and general health of the patient
(Campellone, Joseph, M.D.). In general, gliomas in adults are
more aggressive than in children and usually indicate a worse
outcome. Tumors causing hydrocephalus may cause additional
complications, such as required surgery.
Patients should be sure to voice their concerns, and ask
questions focusing on the disease and its treatment. For many,
the first step in coming to grips with the diagnosis of a brain
tumor is to begin to ask questions. Patients are suggested to
make a list of all their concerns in a small notebook so they
will not forget to ask an important question. It is also
suggested that the patient bring someone along to their doctor
appointments. A family member or friend can help give moral
support, and they can help the patient remember what is told to
them. While at their appointment, the patient should ask for
written information on the topics of concern so they have them
to take home and refer to. There are booklets, pamphlets, fact
sheets, medication cards, videos, and various other educational
materials that will help them understand their disease better
and in a different way. Some people may feel more comfortable
getting a second opinion. Second opinions are considered
standard medical practice. Many doctors are willing to suggest
a specialist, and may even make the appointment for the patient
themselves. Most hospitals offer physician referral services,
which can help the patient find members of their medical staff
with expertise in treating hypothalamic brain tumors (Chicago
Institute of Neurosurgery).
When a patient is diagnosed with a brain tumor they will
naturally have very negative feelings about the disease and the
changes it is causing in their life. They may experience many
emotional reactions: denial, anger, resentment, depression,
resignation, and acceptance. The American Brain Tumor
Association explains how many people go through a state of
temporary denial. The person may feel traumatized and
depressed, and it is common for the person to become numb and
hide or deny their initial feelings. This denial can last a few
days to a few weeks, or even a few months (The American Brain
Tumor Association). As time passes, denial often evolves into a
feeling of anger. Life may feel very unfair. Some people
develop a sense of resignation about living with their brain
tumor and the physical or emotional changes that may come with
the diagnosis. Eventually a sense of acceptance sets in as
people realize the brain tumor is a reality. They slowly come
to grips with the diagnosis, and usually the patient begins to
plan their life in a constructive, meaningful manner and
reassess their values (The American Tumor Association).
Patients may have a hard time telling their family and friends
about their brain tumor. Some may feel like they do not want to
tell them because they do not want to have their spouse, family
or friends worry and fuss over them, and others may feel like a
burden to them. If the person is uncomfortable sharing their
news, they can consider a family conference with the doctor.
When the person speaks to their family about their tumor, it is
helpful to have written information about brain tumors. This
can help the patient and the family to better understand the
disease and the treatment options. Social workers can help the
person talk to their family and help the family live more
comfortably with the diagnosis. Most hospitals have social work
departments, and patients can also find social workers and
counselors at community centers, local service agencies, local
health departments, or schools. The American Tumor association
explains how friends of the patient may find it difficult to
deal with the illness. Some family members or friends may avoid
the patient or conversations with the patient, which can cause
more feelings of depression in the patient. The Association
says that it is important to have a support group for patients,
and that there are nationwide and state support groups for
patients with hypothalamic tumors and their families.
Treatment for hypothalamic tumors depends on the
aggressiveness of the tumor and whether it is a glioma or
another type of cancer. Treatment options involve combinations
of surgery, radiation, and chemotherapy. Dr. Joseph V.
Campellone, from the division of Neurology in Camden, NJ, says
that special radiation treatments can be focused on some tumors
and can be as effective as surgery but pose less risk to
surrounding tissue. Gamma-knife radio surgery allows doctors to
identify abnormal areas in the brain with pinpoint accuracy,
making it possible to treat many disorders affecting the brain
without ever opening the skull. Gamma-knife surgery does not
require an incision; instead, the devise precisely delivers
radiation to an intracranial target. All the beams are aimed at
the target, but each one originates from a different location
outside the skull (National Cancer Inst.). Brain swelling
caused by a tumor may need to be treated with steroids.
Hypothalamic tumors may produce hormones or alter hormone
production, leading to imbalances that may need to be corrected.
In some cases, hormone replacement or suppression may be
necessary. Complications of brain surgery may include bleeding,
infection, brain damage, seizures, and rarely death.
Hydrocephalus can occur with some tumors and can require surgery
or a catheter placement in the brain to reduce spinal fluid
pressure (A.D.A.M.). Fluid normally flows around the spinal
cord and the brain and then is absorbed in the blood stream
(medicallibrary.org). This fluid serves as a cushion to
protect the spinal cord and brain from injury. It also contains
nutrients and proteins to nourish the brain and help it
function, and it carries waste products away to be absorbed by
the bloodstream (medicallibrary.org). When the fluid is
produced faster than it can be absorbed or blocked and collects
inside the brain, the condition is called hydrocephalus. As the
fluid builds up, it causes the ventricles to enlarge and the
pressure inside the head to increase. Risks of radiation
therapy can be damage to the healthy brain cells along with
destruction of the tumor cells. Common side effects from
chemotherapy include loss of appetite, vomiting, and fatigue.
Patients need support, through networking with other
patients, and families, the patient themself will be able to
meet other people learning to live with a brain tumor. One type
of support is the Brain Tumor support groups, who organize
specifically for those with brain tumors. Most brain tumor
group welcome both patients and family members or friends. Some
focus on adult tumors, others on childhood tumors. Cancer
support groups, or cancer wellness groups are more abundant.
Cancer groups offer information, support and nutrition
information for cancer patients. Brain tumor patients facing
radiation or chemotherapy may find valuable support and wellness
resources within the cancer community. Head injury support
groups welcome brain tumor patients also, treating the trauma of
brain surgery as a head injury. Families interested in learning
more about memory retraining, speech, or rehabilitation services
often find shared concerns within head injury groups (Institute
of Neurosurgery & Neuroresearch). Some groups specifically
focus on the person with the tumor, others meet the needs of
both patients and family members. Some groups offer support-
only, and may be run by someone who has experienced a tumor or
by a mental health professionals. Patients need support during
and after their treatment or surgery, whether they are tumor
free or not, this experience has affected their lives in a
dramatic way. Tips from the American Brain Tumor Association
for patients with any type of brain tumors to help them cope
with the disease include: don’t be afraid to ask for help, talk
about your fears, set short term goals, laugh and smile as often
as possible, keep a journal, find purposeful things to do , and
always have faith in yourself.
References
American Accreditation Healthcare Commission, (A.D.A.M.),
www.urac.org
American Brain Tumor Association, Des Plaines, Il., www.abta.org
Campellone, Joseph V., M.D., Division of Neurology, Cooper
Hospital, University Medical Center, Camden, NJ.
Department of Behavioral Medicine, Chicago Institute for
Neurosurgery and Neuroresearch, Chicago, IL.
Kalat, James W., Biological Psychology, 8th edition, 2003
National Cancer Institute, US. National Institute of Health,
www.cancer.gov
www.Medicallibrary.org
Living with Damage to the Hypothalamus:
Spousal or Family Member’s Perspective
By: Hanna Clement
Living with some-one who has a tumor or lesion; caused
by an accidental trauma to the head, a stroke or a penetrating
projectile, ect., can affect many aspects of normal life. Damage
to the hypothalamus can produce many different problems in the
body. According to James Kalat; the hypothalamus is a small area
near the base of the brain just ventral to the thalamus. It has
wide spread connections with the rest of the forebrain and the
midbrain. The hypothalamus contains a number of distinct nuclei.
Partly through nerves and partly through hypothalamic hormones,
the hypothalamus conveys message to pituitary gland, altering
its release of hormones. Damage to a hypothalamic nucleus leads
to abnormalities in one or more motivated behaviors, such as
feeding, drinking, temperature regulation, sexual behavior,
fighting, or activity level (Kalat, 2004). Some of the most
predominant diseases that affect the family and the home life
are; neurophysical diseases, adenohypophysical diseases, and
other hypothalamic syndromes. The most common neurophysical
diseases affected by damage to the hypothalamus are: Diabetes
Insipidus, (SIADH) Syndrome of Inappropriate ADH Secretion and
Cerebral Salt Wasting. Adenohypophysical diseases include:
Panhypopituitarism (Simmonds Disease), abnormalities in growth
and Cushing Disease and Cushing Syndrome. Other Hypothalamic
syndromes that would affect family life include: Precocious
Puberty,
Adiposogenital Dystrophy (Froelich Syndrome), disturbances in
regulation of temperature, appetite and sleep, lastly the Pineal
Gland and Melatonin (Bostrom, 2003).
The Hypothalamus serves as the “head ganglion” of both the
autonomic nervous system and endocrine system. The two are
closely integrated and abundantly connected to the entire limbic
brain. The hypothalamic nucleus, by releasing specific neuro-
transmitter peptides, controls the activities of the secretory
cells of the anterior lobe of the pituitary body. Hormones
released or secreted by cells of the supraoptic and
paraventricular nuclei are transported, in the form of granules,
to the posterior lobe of the pituitary; from there they are
absorbed into the blood stream (Engel,
1997).Under conditions of disease, the neurotransmitter peptides
may be quantitatively increased, decreased, or in some way made
defective; the neurons that synthesize these peptides or their
glandular targets may fail to function or become over
active(Ropper, 2002).
The nuclei of the hypothalamus are conventionally divided
into three paired groups: the anterior group, including the
preoptic, supraoptic, and
paraventriular nuclei, which are mainly neurohypophysical in
their relationships; the middle group, including the tuberal,
arcuate, ventrolatural, and dorsal nuclei; and the posterior
group including the mammillary and posterior nuclei (Ropper,
2002).The Hypothalamus or hypopysis is divided into two lobes:
the anterior, or adenohypophysis, which is derived from the
buccal endoderm(Rathke’s pouch),and; the posterior, or
neurohypophysis, which forms a diverticulum from the base of the
hypothalamus (Bostrom,2003).
The following is a brief description of the hypothalamic
disorders and how they would affect the injured and their family
members.
Diabetes Insipidus is characterized by excretion of large
amounts of dilute urine, which disrupts your body’s water
regulation. To make up for lost water, you may feel the need to
drink large amounts of water. To make up for lost water, you
feel the need to urinate frequently, even at night, which can
disrupt the sleep of you and your partner, on occasion can cause
bedwetting. Dehydration is a major risk with this disorder.
Diabetes Insipidus verses Diabetes Mellitus (which is the common
Diabetes usually called type one), cannot be confused, which is
also affected by the hypothalamus. Diabetes Mellitus results
from a deficiently in the hormone insulin. Hormones are
controlled by the hypothalamus. Living with some-one with this
disorder can be stressful, symptoms can be; irritation, coma,
low blood sugar and many others. Making sure your partner
exercise’s and has a healthy consistent diet can reduce these
symptoms.
Syndrome of Inappropriate ADH Secretion or SIADH is a
neurophysical disease. L-Arginine vasopressin (AVP, ADH), a
nonapeptide, is synthesized in the bodies of magnocellular
neurons in the paired supraoptic nuclei and lateral to the third
ventricle. Absence of AVP leads to excretion of large amounts
dilute urine. Other effects of AVP: the maintenance of blood
volume and osmolality (blood volume rises and serum osmolality
falls) and
hyponatremia.
Cerebral Salt Wasting may be mistaken for SIADH.A salt-
wasting syndrome causes a reduction in serum sodium and in
plasma volume. It may occur in a number of different
intracranial diseases. An increase secretion of atrial
natriuretic factors (peptides that were first identified in the
cardiac atria but are also present in the brain) promotes
diuresis and sodium excretion and may be responsible for
derangement. This occurs in head injury patients. If some-one in
your family had this disorder they would need to be
hospitalized, (putting financial stresses on family members) and
treatment would consist of the administration of intravenous
fluid and sodium rather than fluid restriction.
The first of the Adenohypophysical diseases is
Panhypopituitarism (Simmonds Disease). Simmonds Disease is the
most frequent in this category of diseases. It consists of
multiple glandular deficiencies, many including a nonsecretory
or prolactin-secreting pituitary adenoma. Adenoma compresses
normal glandular tissue, destroying many of the cells and
diminishing the function of others, this results in an
abnormality of growth hormones; ACTH, TSH and FSH-LH. This may
lead to hypothyroidism, adrenal insufficiency and
gonadal failure. In women this is expressed by an irregular
menses or amenorrhea, infertility and galactorrhea. In girls
puberty might be postponed or delayed. In men there is a lack of
libido or impotence.
Abnormalities in growth are also part of the Adenohypophysical
diseases. A deficiency of growth hormone releasing factor (GRH)
and therefore of GH may cause growth retardation. Or it may be
caused by the inheritability inactive
GH molecule, in which case plasma levels of GH are actually
higher, as in some forms of dwarfism. The opposite condition,
gigantism, may occur if an excess of GH is produced before
closure of the epiphyses. Acromegaly is related to pituitary
adenomas, this can lead to enlargement of hands, feet, jaws,
cranium and viscera. This disorder contains other symptoms that
are less apparent (Engel, 1997).
Cushing disease is characterized by a number of symptoms;
truncal obesity, with reddish-purple cutaneous striae,
hypertension, rounded plethoric facies, acne, hirsutism, easy
bruising, osteoporosis, menstrual irregularity, limb weakness
and psychiatric symptoms. Living with someone with this disease
would also be very stressful. Transsphenoidal surgery is the
usual approach to helping relieve the symptoms of this disease.
Medication that has other side effects will also help. The
spouse would deal with mood swings, depression, financial stress
and hospitalization of the effected partner (Boller, 1982).
In regards to eating many changes can take place especially
when damage occurs to the lateral or ventral hypothalamus. The
lateral hypothalamus includes many neuron clusters and passing
axons that contribute to feeding in many diverse ways. The
lateral hypothalamus also controls insulin secretion, alters
taste responsiveness and influences feeding in other ways
(Kalat, 2004). When this area is damaged by a lesion or tumor an
animal or human refuses to eat or drink, it responds as if the
food or water is distasteful. Axons containing dopamine pass
through the lateral hypothalamus, so damage to this area
interrupts these fibers. The interruption of these fibers
results in a chronically inactive, unresponsive animal. In
studies done with rats, experimenters used chemicals that
damaged only the cell bodies; the result was a major loss of
feeding with out lack of activity and response arousal (Kalat,
2004).
A lesion or tumor in the area of the ventromedial
hypothalamus leads to over eating and weight gain. Rats with
damage to this area can double or triple their weight. Symptoms
of this disorder are commonly called ventromedial hypothalamic
syndrome. Lesions must extend outside the ventromedial nucleus
to invade nearby hypothalamic cells and axons (Kalat, 2004).The
hypothalamus can effect eating by increasing aspects to diseases
such as Anorexia and Bulimia.
In many cases, people acquire these diseases later in life,
making it hard on the family or spouse. In order to be as
supportive as possible it is important to be as accepting,
empathetic and nonjudgmental. Since these diseases can affect
many areas of normal life, many that are key to a healthy
relationship such as; sex, eating, sleep, body temperature and
other that have been discussed in this paper, it would
appropriate to seek professional counseling. Clarification and
education may be needed about sexual functioning and effective
communication in contributing to a healthy relationship. Open
communication may help family members deal with feeling of
guilt, self-esteem, anxiety, and empathy towards the victim.
Also, support for the spouse in planning the patient’s care
regarding the specific issues and problems is extremely
important for both parties.
References
Boller, Francois. (1982). Sexual Dysfunction in
Neurological Disorders. New York, New York; Raven Press.
Bostrum, Donald. (2003). Psychiatric Nursing. St.Louis;
Mosbey Publishing.
Engel, Jerome., Williamson, Peter. (1997). Fundamental
Mechanisms of Human Brain Function. New York; New York;
Raven Press.
Kalat, James W. (2004). Biological Psychology. (8th
ed.).Belmont; Wadsworth/Thompson Learning.
Ropper, Allen H., Victor, Maurice. (2002). Manual of
Neurology. (7TH ed.). International Edition, McGraw-Hill
Companies, Inc.
Cause of the Change in Behavior of a Person with Damage to the
Hypothalamus and What to do About the Behavior Change from the
Perspective of the Social Worker
By Nicole Sesson
“The hypothalamus is a small area near the base of the
brain just ventral to the thalamus” (Kalat 90). It makes up
about 1/300 total brain weight in humans, and it is about the
size of an almond (www.factmonster.com). Since the hypothalamus
is attached to the pituitary gland, which is considered the
“master gland,” the hypothalamus is the structure which actually
has master control over promoting or inhibiting hormone release,
affecting many glands (Kalat 327). The main function of the
hypothalamus is to regulate homeostasis, but its wide range of
control affects the generation of behaviors involved in eating,
drinking, temperature regulation, sexual behavior, copulation,
maternal behavior, general arousal, activity level, the sleep-
wake cycle, and emotional regulation of rage, aggression,
embarrassment, escape from danger in “fight or flight”
responses, and pleasure (www.geocities.com). When the
hypothalamus is damaged, specific behavior changes occur
dependent on the lesion location on the hypothalamus. The
affects of such behavior changes can affect a person’s life to
such a degree that a social worker is needed for emotional,
informational, familial, economic, and environmental support
(www.iaswresearch.org).
The hypothalamus controls the pituitary, which consists of
two major glands: anterior pituitary and the posterior pituitary
(which can be considered an extension of the hypothalamus). The
hypothalamus synthesizes the hormones oxytocin and vasopressin,
which are transported to their terminals in the posterior
pituitary, and then released in the blood (Kalat 327). Oxytocin
controls uterine contractions, milk release, certain aspects of
parental behavior, and sexual pleasure. Vasopressin constricts
blood vessels, raises blood pressure, and decreases urine volume
(Kalat 325). The hypothalamus also produces releasing and
inhibiting hormones which travel to the anterior pituitary,
where they control the release of six hormones synthesized
there. The six hormones synthesized in the anterior pituitary
control stimulation of the thyroid gland, production of
progesterone and testosterone, ovulation stimulation, production
of estrogen, maturation of ovum, sperm production, secretion of
steroid hormones by the adrenal gland, milk production, and body
growth (Kalat 325). In general the “lateral and anterior parts
of the hypothalamus support activation of the parasympathetic
nervous system, which causes decreased blood pressure, slowing
of pulse, regulation of digestion, defecation, and reproduction;
while the medial and posterior areas regulate activation
consisting of acceleration of pulse and breathing rates, high
blood pressure, arousal, fear, and anger” (www.geocities.com).
“Damage to the hypothalamus can result from surgery,
physical trauma, degeneration due to old age, disease, a lesion,
or tumor. The results of damage can be varied and depend on the
areas of the hypothalamus involved. Diabetes insipidus can be
caused by hypothalamic damage or by damage to the hypothalamic-
pituitary tract. This disease reduces vasopressin production,
resulting in large volumes of urine being produced at all times.
Other hypothalamic disorders can include sexual abnormalities
(such as premature puberty), psychic disturbances, obesity,
anorexia, temperature regulation disorders, sleep disorders,
disruption of normal circadian rhythms,” cluster headaches, and
thyroid problems (www.webmd.com and www.heumann.org).
A lesion on the preoptic area, which is just anterior to
the anterior hypothalamus, causes a deficit in physiological
mechanisms of temperature regulation (Kalat 298). The preoptic
area monitors body temperature and receives input from
temperature sensitive receptors in the skin and spinal cord to
the extent that if an experimenter heats the preoptic area, an
animal sweats even when the animal is in a cool environment, and
the animal will shiver while in a hot environment, if the
preoptic area is cooled (Kalat 298). Damage to the preoptic area
impairs an animal’s ability to physiologically regulate its body
temperature, such that its body will be cold in a cold
environment. However, although its physiological mechanisms
fail, its behavioral mechanisms can cause an animal to stay warm
in a cool environment by it actively seeking out a warm
environment, (Kalat 298).
“A lesion on the lateral preoptic area impairs osmotic
thirst partly by damage to cell bodies in that area and partly
by damage to axons passing through or near it” (Kalat 301).
Osmotic thirst results from an increase in the concentration of
solutes (ie. NaCl salt) in the body” (Kalat 601). When certain
neurons detect their own loss of water due to osmotic pressure,
which draws water from the cells into the extracellular fluid to
maintain their set point, osmotic thirst is triggered (Kalat
301). The main area responsible for detecting osmotic pressure
is the organum vasculosum laminae terminalis (OVLT) which has
receptors that relay information to several parts of the
hypothalamus (Kalat 301). These areas “include the supraoptic
nucleus of the hypothalamus and the paraventricular nucleus of
the hypothalamus which control the rate at which the posterior
pituitary releases vasopressin, and the lateral preoptic area
which controls initiation of drinking” (Kalat 301). Thus, an
animal with lateral preoptic damage refuses to drink (Bio. of
Behavior lecture 4/6/05).
A lesion on the lateral hypothalamus causes “undereating,
weight loss, low insulin levels, underarousal, and
underresponsiveness” (Kalat 314). In a healthy animal, the
lateral hypothalamus stimulates eating and food-seeking
behaviors, but when this area is damaged, “an animal may starve
to death unless it is force-fed” (Kalat, 310). The lateral
hypothalamus affects taste sensations, the salivation response
to the tastes, and the autonomic responses such as digestive
secretions, so that an animal with damage to this area has
trouble digesting foods (Kalat 311).
A lesion to the ventromedial hypothalamus causes increased
meal frequency, increased appetite, weight gain, and high
insulin levels (Kalat 314). “Some people with a tumor in this
area have gained more than 22 pounds per month, but eventually
the body weight levels off at a stable but high set point, and
total food intake declines to nearly normal levels” (Kalat 312).
There are several reasons why damage to the ventromedial
hypothalamus causes weight gain which include that fact that
“they have increased stomach motility and secretions, their
stomachs empty faster than normal allowing them to be ready for
the next meal sooner, and because damage causes increased
insulin production causing a larger than normal percentage of
each meal to be stored as fat. Even animals with damage to this
area who are prevented from eating, gain weight anyway” (Kalat
312). A lesion to the ventromedial hypothalamus causes weight
gain due to increased frequency of eating, whereas a lesion to
the paraventricular nucleus of the hypothalamus causes weight
gain due to increased meal size (Kalat 314).
The hypothalamus controls the sleeping- waking schedule
(Kalat 157) by releasing the neurotransmitter histamine, which
stimulates arousal (Kalat 275). GABA is a neurotransmitter which
produces sleep, and when there is “a lesion to the GABA
releasing cells of the hypothalamus or basal forebrain, the
result is prolonged wakefulness” (Kalat, 277).
Although the behavior functions of the medial preoptic
area, particularly INAH-3 (interstitial nucleus of the anterior
hypothalamus), have not been tested in humans, this structure
has been found important for sexual activities during animal
studies (Kalat 349- 350). For example, female rats with damage
to this area lose their maternal behavior, and males with damage
to this area decrease sexual behaviors (Kalat 337, 350). These
studies could imply potential sexual dysfunctions for humans
with hypothalamic damage at this location.
Hypothalamic damage and/or brain cancer, not only causes
physiological and behavior changes, but can also cause cognitive
and perceptual changes, as well as family and relationship
changes, and a wide range of environmental changes, which can
often be remedied with the help of an oncology social worker. An
oncology social worker is a professional person trained in
assisting cancer patients, survivors, and their families with a
broad range of services to facilitate social functioning. In the
inpatient setting, “the oncology social worker is usually
expected to make contact with the patient or family member
within 24 hours of the patient’s admission” (Boerckel).
“Since 1974, when the first book was written on oncology
social work, Not Alone with Cancer: A Guide for Those Who Care
by Ruth Abrams, oncology social work has been recognized as an
invaluable service to individuals and their families who are
coping with cancer” (www.iaswresearch.org). “According to
government sources, more than 60% of mental health treatment is
delivered by social workers” (www.naswdc.org). Social work is so
important that March is dedicated as the National Professional
Social Work Month, with 22 years of recognition as of March 2005
(www.naswdc.org). The largest membership organization of
professional social workers in the world, with 153,000 members,
is the National Association of Social Workers (NASW), which was
established in 1955, (www.naswdc.org). This organization offers
business services, and access to publications, programs, and
information which help social workers stay up-to-date about
resources that are available for cancer victims
(www.naswdc.org).
Often when a person is diagnosed with a debilitating
condition, such as brain cancer, many emotions can arise such as
denial, anger, fear, anxiety, loss of self-efficacy, depression,
and loneliness, as well as financial, familial, employment,
insurance, legal, and ethical concerns (Taking Time 2). The
oncology social worker can help alleviate the impact of some of
these issues by: teaching coping strategies and stress
management, providing insight and information about cancer,
providing empowerment and advocacy, addressing the psychosocial
dimensions of care, working with the health professionals who
are treating the patient to help alleviate environmental
stressors, and guide patients to a variety of community and
hospital services or support groups (Taking Time 32;
www.iaswresearch.org). Often times cancer support groups are led
by social workers. During these meetings, members of support
groups can address problems, share joys, share information that
can help a person adapt to changes, learn how to communicate
better with their health professionals, and give each other
positive reinforcement, encouragement, and emotional support
(Taking Time 27). “Previous research has shown that the more
patients are supported by others, the better they adjust to the
cancer” (Hagedoorn). “Social support can reduce psychological
distress, and it reliably enhances the prospects of recovery”
(Taylor). Since many families have trouble adjusting to a
relative with cancer, whether due to: changing roles, added
responsibilities, denial and refusal to discuss the cancer,
uncertainties about sexual intimacy, or children being confused
or scared, there are also support groups for families of cancer
patients (Taking Time 37-40).
“According to Wortman and Dunkel-Schetter cancer is an
experience which can cause conflicting reactions in significant
others: first, feelings of fear and aversion; and second,
beliefs that appropriate behavior toward a victim requires
maintaining a cheerful, optimistic façade. These conflicting
responses may produce ambivalence toward the victim and anxiety
over interacting with the person. Consequently, significant
others may (a) physically avoid the victim, (b) avoid open
communication about the cancer and its consequences, or (c)
engage in forced cheerfulness or minimization of the victim’s
circumstances. As a result, the victim may feel rejected or
abandoned by loved ones” (Dakof). Research also indicates that
another common reaction is being overinvolved or overprotective
which can cause the victim of cancer to feel an additional loss
of self-efficacy (Dakof). A social worker would be able to help
family members come to terms with their conflicting emotions,
facilitate positive communication, and provide information about
additional support groups to further help facilitate
communication, which ultimately would lead to more familial
satisfaction.
According to Win Boerckel CSW, there are special
considerations for cancer patients in the workplace which the
social worker can address. Within the Americans With Disablities
Act (ADA), the cancer patient’s rights are protected. “The
employer is required to make reasonable accommodations to have
the cancer victim remain or return to the workplace, which
involves such factors as changed tours of duty to accommodated
treatment schedules; reconfiguration of tasks to accommodate
changes in abilities; the right to grievance, and to report
perceived failure on the employer’s part to the EEOC” (Boerckel
interview). A social worker can assist the cancer victim with
information and resources if they are having related employment
issues.
As already implied, hypothalamic damage can cause
devastating effects on a person’s life as well as the lives of
those close to them. The social worker helps ease a person’s
transition across the various stages, from detection, diagnosis,
treatment, and survivorship (www.naswdc.org).
References
Boerckel, W. (5/12/2000). Living well despite cancer with
Win Boerckel. WebMD Live Events Transcript.
http://my.webmd.com/content/article/1/1700_50458.htm.
Dakof, G.A., Taylor, S.E. (1990). Victims’ perceptions of
social support: What is helpful from whom? Journal of
Personality and Social Psychology, 58(1), 80-89.
Hagedoorn, M., Kuijer, R.G., Buunk, B.P., DeJong, G.M.,
Wobbes, T., Sanderman, R. (2000). Marital satisfaction in
patients with cancer: Does Support From Intimate Partners
Benefit Those Who Need It the Most? Health Psychology,
19(3), 274-282.
Institute for the Advancement of Social Work Research
(2003). A Report to the National Cancer Institute: Social
work’s contribution to research on cancer prevention,
detection, diagnosis, treatment and surviviorship.
Washington, D.C. www.iaswresearch.org.
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