Chapter 12 Flashcards
Ventricles
fluid-filled chambers that are continuous to one another and to the central canal of spinal cord
What are ventricles filled with?
cerebrospinal fluid (CSF)
What are ventricles lined by?
ependymal cells (neuroglia cells)
Subarachnoid space
is the interval between the arachnoid membrane and the pia mater
Cerebral hemispheres
form superior part of brain
Cerebral hemispheres amount how much brain mass?
83%
Cerebral cortex
is “executive space” of brain and site of conscious mind
Conscious mind functions
awareness, sensory perception, voluntary motor initiation, communication, memory storage, understanding
Broca’s area
motor speech area that directs muscles of speech production
Pyramid cells
large neurons that allow conscious control of precise, skilled, skeletal muscle movements
Pyramidal (corticospinal) tracts
formed from long axons that project down spinal cord
Motor homunculi
upside-down caricatures represent contralateral motor innervation of body regions
Cerebral cortex
premotor cortex, broca’s area, frontal eye field, visual areas, auditory areas, vestibular cortex, olfactory cortex, gustatory and visceral sensory area, multimodal association areas, anterior association area, posterior association area
Primary somatosensory cortex
receives general sensory information from skin and proprioceptors of skeletal muscle, joints, and tendons
Somatosensory homunculus
upside-down caricatures represent contralateral sensory input from body regions
Wernicke’s area
involved in understanding written and spoken language
Limbic association area
provides emotional impact that makes a scene important to us and helps establish memories
Thalamus
acts to mediate sensation, motor activities, cortical arousal, learning and memory
Infundibulum
stalk the connects to pituitary gland
Hypothalamus
main visceral control and regulating center that is vital to homeostasis
Chief homeostasis controls
controls autonomic nervous system and initiates physical responses to emotions
Hypothalamus functions
regulated body temperature, regulated hunger and satiety in response to nutrient blood levels or hormones, regulates water balance and thirst, regulates sleep-wake cycles, controls endocrine system functions
Pineal gland (body
secretes melatonin that helps regulate sleep-wake cycle
Brain stem three regions
midbrain, pons, medulla oblongata
Substantia nigra
functionally linked to basal nuclei and degeneration of this area occurs in Parkinson’s disease
Pons
maintain normal rhythm of breathing
Medulla oblongata contains what?
choroid plexus
Choroid plexus
capillary-rich membrane that forms cerebral spinal fluid
Functional groups of medulla
cardiovascular and respiratory centers
Cerebellum
major role in balance
Limbic system includes
amygdaloid body and cingulate gyrus
Limbic system function
puts emotional responses to odors
output relayed via hypothalamus
Hypothalamus plays a role in what kind of illnesses?
psychosomatic illnesses
Reticular activation system (RAS)
conscious and alert, filters out receptive, familiar, or weak stimuli
Meninges
dura mater, arachnoid mater, pia mater
Cerebrospinal fluid (CSF)
forms a liquid cushion of constant volume around brain
Choroid plexus
cluster of capillaries that hangs from roof of each ventricle, enclosed by pia mater and surrounding layers of ependymal cells
Substances must pass through three layers before gaining entry to neurons
- continuous endothelium of capillary walls
- thick basal lamina around capillaries
- feet of astrocytes surround neurons
Epidural space
cushion of fat and network of veins in space between vertebrae and spinal dura mater
Cauda equina
collection of nerve roots at inferior end of vertebral canal
Spinal Cord cross-section anatomy
gray matter is located in core, white matter outside
Central canal
runs length of cord and filled with CSF
