Flashcards in Neuropsychology 5 Deck (36):
What is thyroxin?
The hormone released by the thyroid, by which it controls metabolism.
What is metabolism?
The rate at which the body burns calories.
What is cretinism?
A syndrome of physical maldevelopment and intellectual impairment that results from early thyroid deficiency.
What is hypothyroidism?
A syndrome resulting from undersecretion of thyroxin in adulthood. It is characterized by slow metabolism, reduced appetite, weight gain, lowered heart rate and body temperature, decreased sex drive, depression, and cognitive deficits such as impaired concentration and memory.
What is hyperthyroidism?
A syndrome resulting from oversecretion of thyroxin in adulthood. It is characterized by elevated body temperature, increased metabolic rate and appetite, weight loss, accelerated heart rate, nervousness, agitation, fatigue, insomnia, mania, and decreased attention span. Aka Grave's Disease.
What is the function of insulin?
It helps the body absorb and make use of glucose and amino acids.
What is diabetes millitus?
A syndrome resulting from the pancreas' inability to produce insulin. It is characterized by high glucose levels in the blood, which result in mineral loss, low blood pressure, reduced blood flow, and can result in death.
What is hypoglycemia?
A syndrome resulting from oversecretion of insulin. It is characterized by hunger, dizziness, headaches, blurred vision, heart palpitations, anxiety, depression, and confusion.
Name the four types of sensory receptors.
Photoreceptors (light), chemoreceptors (taste and smell), mechanoreceptors (touch and hearing), thermoreceptors (heat/cold).
How are rods and cones distributed on the retina?
Cones are fairly dense, especially so in the fovea; moving outward from the fovea, the proportion of rods increases and that of cones decreases.
Describe the sequence of synapses from photoreceptors to the optic nerve.
Rods and cones (photoreceptors) synapse with bipolar cells. Bipolar cells synapse with ganglion cells. The axons of ganglion cells bundle to form the optic nerve.
Where do most optic nerve fibers terminate?
Lateral geniculate nucleus of the thalamus. The LGN then projects to the primary visual cortex of the occipital lobe.
How are signals from the auditory nerve distributed between brain hemispheres?
About 60% of auditory nerve signals cross to the opposite side of the brain.
Name the two membranes of the inner ear between which hair cells are located.
Basilar and tectorial.
What is the "pain-prone" theory of pain?
For some, chronic pain may be a form of masked depression; the mood disorder may precede the pain. There is evidence supporting an environmental or genetic predisposition for developing pain.
What is the "gate" theory of pain?
Large myelinated nerve fibers serve as gates for small, unmyelinated afferent fibers the pain signals from which are passed or not by the gating fibers. Gating mechanism can be activated locally by stimulation from heat/cold or massage, or distally from the brain through distraction.
What is the "endorphin" theory of pain?
The brain must produce opiate-like substances for pain relief, as evidenced by the fact that opioids bind with existing receptors.
There is one sense in which the nerve fibers do not pass through the thalamus: what is it and into what part of the brain do they project?
The olfactory nerves project directly into the limbic system and do not cross to opposite sides of the brain.
What are pheromones?
Scents that initiate sexual activity and are used to mark territory.
What is psychophysics?
The study of the relationship between the magnitude of physical stimuli and sensation.
What is absolute threshold?
The minimum intensity for a stimulus to be detected 50% of the time.
What is Stevens' Power Law?
There is an exponential relationship between the magnitude of a stimulus and its sensation, but the exponent varies by stimulus.
What is dysarthria?
Problems in speech articulation, often mistaken for aphasia. A common symptom of Parkinson's, Huntington's, or multiple sclerosis.
What is alexia?
Word blindness, a focal dysfunction typically caused by a brain lesion. DiffDx, dyslexia: dyslexia is a learning disorder and is developmental.
What is constructional apraxia?
Inability to draw or copy simple figures or arrange blocks in a pattern.
How are age and tumor location related?
Children are more likely to develop brainstem or cerebellar tumors, while adults are more likely to develop cortical tumors.
List five symptoms that suggest the presence of a brain tumor.
Dull, generalized headaches; partial, adult-onset seizures; projectile vomiting; vision and hearing changes like visual field disturbances and tinnitus; focal neurological signs.
What areas of the brain does the middle cerebral artery supply?
Parts of the frontal, temporal, and parietal lobes, and the basal ganglia.
What consequences are common for strokes occurring in the middle cerebral artery?
Contralateral hemiplegia and sensory loss (esp. face and arm); dementia; contralateral visual field loss (aka homonymous hemianopsia).
What areas of the brain does the anterior cerebral artery supply?
Areas of the frontal and parietal lobes, the corpus callosum, and the caudate nucleus.
What consequences are common for strokes occurring in the anterior cerebral artery?
Contralateral hemiplegia and sensory loss (usu. lower limbs), dementia, and affective disturbance.
What areas of the brain does the posterior cerebral artery supply?
Temporal and occipital lobes and thalamus.
What consequences are common for strokes occurring in the posterior cerebral artery?
Cortical blindness and other visual deficits, anterograde amnesia, and agitated delirium.
What is the most common location for strokes?
The middle cerebral artery.
What is a common consequence of stroke, regardless of artery involved?
Impairment of cerebrospinal fluid flow.