Teena George
Neurology project #1
Dr. Morgan, Psych. 472
Fall Semester, 1999
Subject:  Frontal Lobe Damage and
 Premotor Cortex Symptoms

The frontal lobe contains both a left and a right 
hemisphere.  These hemispheres are responsible for special 
task.  Many of those tasks involve sending and receiving 
messages from the brain to other locations in the body.  
There are many problems correlated to head injuries and 
strokes that cause lesions on the brain.  A brain lesion can 
be the result of non-penetrating or penetrating blow to the 
skull.  A lesion is destruction of tissue.  A brain lesion 
is a naturally or experimentally caused by the destruction 
of an injured person's brain tissue.  Throughout this paper 
I will address each of these issues and explain any 
unfamiliar terminology.   
	The brain is unilateral which means if you are injured 
on one side of the brain, the other side of the body would 
be effected.  The workings of the brain are connected 
through this unilateral process.  The right side of the 
brain sends messages to the left potion of the body, which 
is then sent back to the right side of the brain causing a 
reaction of to occure in the left anterior     
There are special functions performed by each side of the 
hemisphere.  For example: the left area of the frontal 
cortex has to do with speech and language, and the right 
hemisphere is important for recognizing faces and emotions.  
The premotor cortex is located in front of the primary motor 
cortex.  The primary motor cortex is located adjacent to the 
central sulcus.  Sulci is the deep fissures in the brain 
that separate gyri.  Gyri is the folds that give the brain 
its character..  The central sulcus is the line from the tip 
of one ear to the other, directly in the center lateral part 
of your brain.  What I will be referring to is the Premotor 
Cortex in head injury and stroke patients/victims.
The premotor cortex is the area of the brain used in 
initiating and sequencing movements.  There are many 
specific roles in sensory guided movements that are 
activated in a premotor response to visual, auditory, and 
somatosensory stimuli.  The structure of the premotor cortex 
resembles the primary motor area, but their duties are 
completely different, yet strongly correlated.  
	A stroke is caused by many risk factors.  The two most 
important are hypertension (high blood pressure), in which, 
the walls of the arteries are weakened by this process.  The 
other atherosclerosis (thickens the lining of the arterial 
walls), which 
narrows the arteries.  Seniors are often effected most by 
this disorder.  Maintaining a proper diet and exercise can 
help in the prevention of these factors but some are 
hereditary.
A stroke causes damage to the brain because the blood supply 
is either interrupted in its flow or leaking of blood is 
outside of the vessel walls.  While the brain is swelling 
the movement is impaired until the swelling decreases.  
Hemiplegia is the one sided weakness or paralysis 
experienced with stroke.  This is again linked to the 
unilaterally of the brain.  One area is effected in the 
brain, but it will impair bodily sensations, movements, and 
even brain function.  The stroke patients are unable to make 
voluntary motor or eye movements.  This makes picking up a 
glass a difficult and emotional task, whereas non stroke 
patients have no prolonged movement in this task.  Most 
people often don't think or feel like they are using their 
own body parts.  The paralysis is usually temporary and the 
patients are, usually, able to walk and use all their limbs 
again.  Unfortunately, intellectual impairment is often 
permanent.  The phenomenal part about it is that the brain 
will learn to adapt for the non working part.  The brain 
relearns and teaches other parts of the brain or muscle 
groups to make up for the damaged area.
	Head injury is often a result of (but not limited to) 
traffic accidents, sports injuries, falls, assaults, work or 
home related accidents, or bullet wounds.  Almost everyone 
has had a minor head injury, non penetrating.  These rarely 
cause any trauma or problems for the individual.  A person 
may loose consciousness, have a tender point of impact, and 
a headache.    
Traumatic brain damage includes penetrating objects into the 
brain.  Bullet wounds, for example, can cause a person to 
loose consciousness and have epileptic seizures.  People 
that get injured during their lifetime are more 
disadvantaged than a person that has been disabled their 
entire lives.  The disadvantaged person has to reorient 
their live completely.  This is very devastating to a person 
that is struggling with psychological and physically 
changes.  
Some premotor symptoms include: thinking ahead, planning, 
organizing, voluntary movements, a loss of learned behaviors 
(some) become isolated fragments, and poor copying skills.  
Frontal damage causes oculomotor difficulties also.  They 
are unable to make quick eye movement or succades.  Succades 
are when the eyes move in abrupt jerking motion.  When a 
person fixates (focuses real hard) on an object the eyeball 
will jump back and forth between two points that are several 
inches apart.  If a paralyzed person wills their movement 
left, the eyes would not move.  No commands or cues cause a 
reaction, the eyes are paralyzed with the body.  The other 
perceptual condition is when the eyeball is pushed there is 
no displacement of the world, that means that no movement is 
seen at all from pushing in the corner of ones eye.  The 
retinal image is there but there is no command signal to the 
going to the extraocular muscles.  This is a deficit seen in 
frontal lobe injury patients.  The problem is that the brain 
is not informing the other region on its intention to move.  
This is called an impaired corollary discharge.
	Some other premotor disorders include apraxia, ataxia, 
hemipledia, papaplegia, chorea, and athetosis.  Apraxia is a 
disorder concerning voluntary movement which are not caused 
by motor weakness,  paralysis,  sensory loss or 
intellectual,  motivational  or  attentional impairments.  
Ataxia is the failure of muscle coordination or an 
irregularity of muscular action.  Hemiplegia is the complete 
or partial paralysis of one side of the body.  Paraplegia is 
the paralysis of the legs and the lower half of the body.  
Chorea is the non-stop occurrence of involuntary,  jerky 
movements.  Athetosis is a slow writhing movement in the 
hands.  
	Some of the machines used to measure and diagnose both 
of these injuries, stroke and head injury, are 
Electroencephalography (ECG), Magnetoencephalography (MEG), 
Computerized axial tomography (CT or CAT), Positron emission 
tomography (PET), Functional magnetic resonance imaging 
(fMRI).  There are also biochemical techniques, other forms 
of x-rays, blood test, and many other breakthrough 
technology sources in finding detection of brain damage.   
Behavioral changes that might be noticeable by friends, 
family, and/or co workers.  Many people feel like they are 
only half a person when trauma to the brain is experienced.  
There are many fundamental issues that proceed a patient 
after one of these injuries.  To start with the recovery is 
unpredictable in head injuries so doctors are forced to give 
opinions that have no predictability's.  There are many 
ongoing treatments and appointments that consume an injured 
person's time.  Rehabilitation could take years before any 
results are seen.  They have a difficult time with 
organizing their thoughts, which make it difficult to 
communicate.  They are usually frustrated and withdrawn in 
stressful situations.  And last, to only name a few, the 
habituated learning styles the person injured is usually 
accustomed to is not always an effected form of learning 
anymore.  As you could see, a person experiencing head 
trauma is dealing with many issues to regain their former 
lifestyles.  As friends, family, and/or co workers we should 
all try to understand and research why they are not 
"themselves" lately.
Treatment includes prescription drugs, surgical procedures, 
and various forms of therapy.  A few of the theroputic 
rehabilitation treatments include occupational and physical 
therapy.  There is generally a need for psychological and/or 
neurological rehabilitation as well.   It is always good to 
be positive and have a hopeful outlook for whomever may be 
experiencing these trauma.
	Some of the medical terms for conditions that result 
from trauma are: Contusion, a bruise caused from brain 
impact against the skull. Coma, a random and uncontrolled 
electrical firing in the brain resulting in seizures.  
Concussion, a head trauma resulting in possible loss of 
consciousness.  Hematoma, formed by a hemorrhage, blood in 
the brain.  Shearing, the tearing of nerve fibers caused by 
twisting of the brain inside ones skull.

References:
Human Neuropsychology   G. Neil Martin  Prentice Hall  1998

Psychology  Fourth Edition  David G. Myers Worth Publishers, 
Inc. 1995

Left Brain, Right Brain  Sally P. Springer  W.H. Freeman And 
Company  1981

The AMA Encyclopedia of Medicine  Charles B. Clayman, M.D.   
Random House  1989
 
Intro to Psycology  Seventh Edition  Denis Coon  West 
Publishing Company  1995

Perception Third Edition  Robert Sekuler McGraw-Hill, Inc. 
1994

Human Mind  Robert J. Sternberg  Harcourt Brace & Company 
1995

Head Injury Association of Waterloo Welington  
http.//www.waterloo/
 Humboldt State connection 
http://madrone.humboldt.edu/campus

Encarta Online  info@wireheading.com

 http://debra.dgbt.coc.ca/~andrew/epilespy//

Brain Center  4229 Bardstown Rd. 3330 Louisville, Ky 40218 
(800)592-1117

Barrow Neurological Institute.  
www.amnesia//

    

Copyright © 1999, Dr. John M. Morgan, All rights reserved - This page last edited 13 - December, 1999
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