Textbook Notes (280,000)
CA (160,000)
York (10,000)
PSYC (4,000)
Chapter

Neural Basis of Behavior: Ch 15


Department
Psychology
Course Code
PSYC 3250
Professor
Pauline Charlton

This preview shows pages 1-3. to view the full 12 pages of the document.
Ch 15: neurological disorders
Tumors
Tumor: mass of cells that grow uncontrollably and serves no useful function; can be
malignant (cancerous) or benign (harmless)
Malignant tumors can become infiltrated into other healthy cells, and when a surgeon
cuts it away, some cells maybe missed causing a new tumor to be created
Malignant tumors can also become metastases - these cancerous cells can travel
through the bloodstream and capillaries, and can grow tumors in other regions of the
body
Tumors damage brain tissue two ways: (1) they compress the brain tissue and can
block the flow of CSF (can happen with benign tumors); (2) malignant tumors can com-
press and infiltrate, which destroys healthy brain cells
Since nerve cells cannot divide, tumors do not arise from them; however they can
arise from glia cells, which is known as gliomas, which are both malignant and fast
growing
Once a surgeon has removed most of the tumor, radiation can be used to destroy the
rest, as tumors are normally sensitive to radiation
Meningioma: a benign tumor consisting of cells found in the dura mater and arachnid
membrane
See table 15.1 on pg. 522 for other types of tumors
Seizure disorders
Following strokes, seizure disorders are the 2nd most important category of neurologi-
cal disorders
Seizure: period of sudden extensive activity of cerebral neurons

Only pages 1-3 are available for preview. Some parts have been intentionally blurred.

Convulsions: when neurons of the motor system are involved in a seizure, wild, un-
controllable activity of the muscles is displayed
Partial seizure: have a definite focus (restricted to a small part of the brain), either in
a scarred region, caused by an injury, or a developmental abnormality
Simple partial seizure: cause changes in consciousness, but do not cause a loss
of consciousness
Complex partial seizure: based on their location and severity, these seizure show
a loss in consciousness
Generalized seizures: widespread and involve most of the brain; can either grow
from a focus, or their origin may not be discovered at times
Grand mal: most severe form of seizures; is generalized and also includes convul-
sions
Aura: takes place seconds before a grand mal, which causes excitation of neurons
in the surrounding seizure focus
Tonic phase: beginning stage of a grand mal where the patients muscles contract
forcefully - patient is completely unconscious by now
Clonic phase: 15 sec after the tonic phase, the muscles tremble and start convuls-
ing (starts off fast and then eventually slows down), the eyes may roll and the auto-
nomic system causes sweating and salivation
30 seconds after, the person relax and go into an unresponsive sleep for around 15
mins; they may wake up after this, but will most likely go back to sleep for another
few hours
Partial seizures are less dramatic, as they include motor changes, sensory changes or
both; simple partial seizures can eventually become more severe with every seizure that
occurs and can change from being a simple partial seizure, to a complex one

Only pages 1-3 are available for preview. Some parts have been intentionally blurred.

Absence aka petit mal: seizures which are commonly found in children and is a gen-
eralized seizure; during this seizure, a child will stop what they are doing and stare into
space while repeatedly blinking their eyes - can happen several hundred times a day,
and if not diagnosed, can lead to disruptions with school performance and the children
are just considered unmotivated
Status epilepticus: a condition in which a patient undergoes numerous seizures with-
out regaining consciousness (because of an excessive amount of glutamate release),
and can also create brain damage to the hippocampus
Causes to seizures include scarring of the brain, head injury, drugs, infections that
cause high fever, genes that control ion channels
During alcohol withdrawal, NMDA receptors maybe involved with seizures - the recep-
tors maybe suppressed which is what causes the seizure
Seizures are treated with anticonvulsant drugs, which work to increase inhibitory
synapses
After surgery, which involves removing brain tissue, peoples performance on tests im-
proves bc the both the tumor and compensatory inhibitory neurons are both removed,
decreasing irritability, and allowing the person to function normally
Ketogenic diets: way to obtain relief from seizures - the diet consists of increasing
ones calorie intake by eating more fats, thus increasing their production of ketone com-
pounds that provide nourishment to the brain
Cerebrovascular accidents
~600,000 strokes per year in USA, which increases in individuals based on age
Hemorrhagic strokes: caused by bleeding within the brain, from malformed blood
vessels or from blood vessels weaken by high blood pressure, which leads to damage in
the brain - medication or surgery can be used to prevent another hemorrhage from hap-
pening
You're Reading a Preview

Unlock to view full version