【精品】PPT课件 Neuroplasiticitych. 10and Cerebral Hemispheresch. 16.ppt

Neuroplasiticitych. 10and Cerebral Hemispheresch. 16
Neuropsychological Disorders, Damage S, and Neuroplasticity
Ch. 10
Outline
Causes of Brain Damage
Neuropsychological Diseases
Neural Damage: Degeneration, Regeneration, anization, and Recovery
Causes of Brain Damage
Tumors
Group of cells growing independently of the rest of the body; tumor can be encapsulated or infiltrating; it can be benign or malignant
Metastatic tumors originate in an and spread to another; the symptoms of multiple brain tumors are often the first signs of lung cancer
20% of brain tumors are meningiomas that grow in the meninges; they are encapsulated and benign
Cerebrovascular Disorders
Stroke is mon term
May be due to cerebral hemorage, the bursting of aneuryms (balloon-like dilations of weak areas of blood vessels)
Cerebrovascular Disorders
Strokes are also caused by a cerebral ischema, a disruption of blood supply to an area of the brain
In thrombosis, a plug es lodged at the site of formation; the plug may be due to a blood clot, fat, oil, cancerous cells, air bubbles
In embolism a plug travels and es lodged in a smaller blood vessel
In arteriosclerosis the blood vessel walls thicken and the space inside narrows from accumulation of fat
Cerebrovascular Disorders
The brain damage caused during an ischemic episode is believed to be due to an excessive release of excitatory amino acids
Glutamate, the brain’s most prevalent excitatory neurotransmitter, is released in excessive quantities when blood vessels are blocked
Cerebrovascular Disorders
The excessive glutamate overactivates glutamate receptors on the postsynaptic membrane sites thus too many Na+ and Ca++ ions are allowed to enter the postsynaptic neuron; this overabundance of ions triggers either
More excessive release of glutamate, causing a cascade of this toxic effect
Triggers a sequence of reactions that kills the postsynaptic neuron
Cerebrovascular Disorders
The brain damage caused by ischema takes a while to