Ch. 12 Mastering A&P

conscious control of skeletal muscles origin of corticospinal tracts post-central gyrus cell bodies of pyramidal neurons

-Broca's area; posterior association area; auditory areas; visual areas *primary motor cortex; premotor cortex; Broca's area; frontal eye field -primary motor cortex; premotor cortex; prefrontal cortex; gustatory cortex -primary somatosensory cortex; somatosensory association cortex; visual areas

do not understand language *can understand language, but have difficulty speaking do not understand written communications, but they can speak clearly and intelligibly can communicate through writing or sign language, but they cannot speak Patients with lesions involving Broca's area can understand language but have difficulty speaking (and sometimes cannot write or type or use sign language) - this disorder is called expressive, or Broca's, aphasia. On the other hand, patients with lesions involving Wernicke's area are able to speak but produce a type of nonsense often referred to as "word salad" - this disorder is called receptive, or Wernicke's, aphasia. These patients also have great difficulty understanding language.

Alzheimer's disease Huntington's disease mad cow disease Parkinson's disease Alzheimer's disease is a degenerative brain disease in which beta-amyloid peptide deposits and neurofibrillary tangles appear. Marked by a deficit of ACh, it results in slow, progressive loss of memory and motor control and increasing dementia. Alzheimer's patients represent nearly half of the people living in nursing homes. Between 5 and 15% of people over 65 develop this condition, and for up to half of those over 85 it is a major contributing cause in their deaths.

arachnoid mater membranous part of the dura mater periosteal part of the dura mater pia mater

The membranous part of the dura mater, called the meningeal layer, forms the true external covering of the brain and continues caudally in the vertebral canal as the spinal dura mater. The meningeal layer does not provide passageways for CSF to leave the subarachnoid space and enter the venous blood of the sinus. The subarachnoid space is filled with CSF. Knoblike projections of the arachnoid mater, called arachnoid villi, protrude superiorly through the dura mater and into the superior sagittal sinus. These villi provide a passageway for CSF to leave the subarachnoid space and enter the venous blood of the sinus.

By processing and interpreting impulses from the motor cortex and brain stem nuclei, as well as the sensory pathways, the cerebellum provides the precise timing and appropriate patterns of skeletal muscle contraction for the smooth, coordinated movements and agility needed for daily activities (e.g., driving, typing, and tying our shoes). It also plays a poorly understood role in cognition. Cerebellar activity occurs subconsciously (we are not aware of it).

Memory is a function of the brain (not the spinal cord).

It means they cross from one side of the CNS to the other at some point along their journey.

It means that tract fibers are spatially arranged in a way that reflects the orderly mapping of the body. For example, in an ascending sensory tract, somatotropy refers to the fact that fibers transmitting inputs from sensory receptors in the superior parts of the body lie lateral to those conveying sensory information from inferior body regions.

The collection of nerve roots at the inferior end of the vertebral canal is named the cauda (tail) equina (horse) because it resembles a horse's tail. This strange arrangement reflects the fact that during fetal development, the vertebral column grows faster than the spinal cord, forcing the lower spinal nerve roots to "chase" their exit points inferiorly through the vertebral canal.

conus medullaris is the name of the end of the spinal cord; the spinal cord does not reach the end of the vertebral column; growing down to the end of the vertebral column is a collection of nerve roots that resembles a horse's tail; this collection of fibers is called the cauda equina. The collection of nerve roots at the inferior end of the vertebral canal is named the cauda (tail) equina (horse) because it resembles a horse's tail. This strange arrangement reflects the fact that during fetal development, the vertebral column grows faster than the spinal cord, forcing the lower spinal nerve roots to "chase" their exit points inferiorly through the vertebral canal.

It's not the primary motor cortex. The primary motor cortex of the brain functions to control voluntary skeletal muscle activity via contralateral innervation. It's not the premotor cortex. The premotor cortex of the brain determines which voluntary skeletal muscle groups will be activated and how they will be used prior to stimulating the primary motor cortex. However, none of these answers are correct. Review central nervous system control of voluntary skeletal muscle contractions and compare it to reflex arc activation.

The superchiasmatic nucleus. This area of the hypothalamus is important in determining the circadian rhythm that sets our sleep-wake cycles. It is our biological clock.

Mitochondria are cytoplasmic organelles that produce ATP that provide energy for other cellular activities. Oxygen consumption during sleep resembles that of the waking state. In coma patients, in contrast, oxygen use is always below resting levels.

the medulla oblongata The medulla contains many important functional groups of visceral motor nuclei, including the cardiovascular (CV) and respiratory centers. The CV center includes the cardiac center, which adjusts the force and rate of heart contraction to meet the body's needs, and the vasomotor center, which changes blood vessel diameter to regulate blood pressure. The respiratory centers generate the respiratory rhythm and (in concert with pontine centers) control the rate and depth of breathing. The olivary nuclei and cough, sneezing, swallowing, and vomiting centers are also in the medulla.

pons (p. 448)

medulla oblongata

...

the most superficial region is the cortex; it consists of gray matter; deep to the cortex is internal white matter; and the third the basal ganglia, which are small islands of gray matter located deep within the white matter

the cerebral cortex contains neuron cell bodies, dendrites, and unmyelinated axons, but no fiber tracts

pyramidal tracts, aka corticospinal tracts

damage to the primary visual cortex results in blindness

they can still see, but they don't know what they are looking at; but also they can apparently be blind if the visual association area is damaged, even thought that's not how I understood the book

person is unable to perform learned motor skills of a repetitious nature such as playing an instrument or typing, but they are still able to move

the person loses voluntary muscle control

caudate nucleus

1. caudate nucleus 2. putamen 3. globus pallidus

basal ganglia

corticospinal tracts

the limbic system

eight structures make up the limbic system; the fornix links them together

the amygdala and the anterior part of the cingulate gyrus; the amygdala allows us to recognize angry or fearful facial expressions, assesses danger; the cingulate gyrus helps us to express our emotions through gestures and in resolving mental conflicts when we are frustrated

septal nuclei, cingulate gyrus, parahippocampal gyrus, dentate gyrus, hippocampus, amygdala, hypothalamus, anterior nucleus of the thalamus

loss of proprioception

Parkinson's disease

cerebral aqueduct

1. prefrontal cortex 2. language areas 3. general (aka common) interpretation area 4. visceral association area

so far three: 1. prefrontal cortex 2. hippocampus 3. thalamus the cerebral hemispheres diencephalon: thalamus, hypothalamus, epithalamus

brain stem: midbrain, pons, medulla oblongata cerebellum