Biological Basis of Nervous System Disorders

Question 1

Schizophrenia

Answer 1

-Most potential causes are genetic, but trauma at birth, especially hypoxemia, is also considered to be a risk factor
-Significant data shows that it is inherited
-Highly associated with an excess of dopamine in the brain
-Neuroleptic: medications that depress nerve function

Question 2

Depressive and Bipolar disorders

Answer 2

-Abnormally high glucose metabolism in the amygdala (depression)
-Hippocampal atrophy after a long duration of illness
-Abnormally high levels of glucocorticoids (cortisol)
-Decreased norepinephrine, serotonin, and dopamine (monoamine theory of depression)
-Increased norepinephrine and serotonin (monoamine theory) (bipolar disorder)
-Higher risk if parent has bipolar disorder
-Higher risk for persons with multiple sclerosis

Question 3

Alzheimer’s Disease

Answer 3

-Type of dementia characterized by gradual memory loss, disorientation to time and place, problems with abstract thought, and a tendency to disorientation to time
-Diffuse atrophy of the brain on CT or MRI
-Flattened sulci in the cerebral cortex
-Enlarged cerebral ventricles
-Deficient blood flow in parietal lobes, which is correlated with cognitive decline
-Reduction in levels of acetylcholine
-Reduction in choline acetyltransferase (ChAT), the enzyme that produces acetylcholine
-Reduced metabolism in temporal and parietal
-Senile plaques of -amyloid (a misfolded protein in -pleated sheet form)

Question 4

Parkinson’s Disease

Answer 4

-Biological basis of this disease is decreased dopamine production in the substantia nigra, a layer of cells in the brain that functions to produce dopamine to permit proper functioning of the basal ganglia
-The basal ganglia are critical for initiating and terminating movements, as well as sustaining repetitive motor tasks and smoothening motions
-Bradykinesia: slowness in movement
-Resting tremor: a tremor that appears when muscles are not being used
-Pill-rolling tremor: flexing and extending the fingers while moving the thumb back and forth, as if rolling something in the fingers
-Masklike faces: static and expressionless factions features, staring eyes, and a partially open mouth
-Cogwheel rigidity: muscle tension that intermittently halts movement as an examiner attempts to manipulate a limb
-Shuffling gait with stooped posture