Ch. 14 - Brain and Cranial Nerves II Flashcards
(50 cards)
What are the functions of the cerebellum?
- evaluate movements that cerebrum is ordering
- finetune motor function (voluntary and involuntary movement)
- maintain balance
- store memories of learned movements
What are some structures in the cerebellum?
- cerebellar hemispheres (L, R)
- flocculonodular lobe
- cerebellar peduncles (paired; sup, mid, inf)
What is the function of the cerebellar hemispheres and what do they consist of?
- control subconscious aspects of sk muscle movements
- each consist of ant and post lobes separated by fissures
What is the function of flocculonodular lobe?
maintain equilibrium/balance
What is the function of cerebellar peduncles?
- help coordinate muscle movement
- white matter tract attach cerebellum to brainstem
What is ataxia?
loss of ability to coordinate movement
What can occur when the cerebellum is damaged?
- ataxia
- no sense of proprioception
- uncoordinated speech muscles
- abnormal stumbling
What does the diencephalon include?
thalamus, hypothalamus, epithalamus
What does the thalamus consist of?
- constitutes 80% of diencephalon
- paired oval masses of grey matter connected across the 3rd ventricle by interthalamic adhesion
- contains nuclei and tracts
What are the functions of the thalamus?
- relay station for sensory and motor function
S - filters info from spinal cord/brain stem to the cerebral cortex; each region of thalamus contains nuclei that connect to specific regions of cc
M - sends info from cerebellum/basal nuclei to primary motor areas of cerebral cortex
What are the 4 main regions of the hypothalamus?
- mammillary
- tuberal region
- supraoptic
- preoptic
What are some functions of the hypothalamus?
- control of the ANS
- hormone production
- regulation of emotional and beh patterns
- regulation of eating and drinking
- control of body temp
- regulation of circadian rhythms/states of consc
Describe how the hypothalamus controls the ANS
- axons from hypothalamus extend to sym/parasym nuclei in brainstem and spinal cord
- stimulate autonomic effectors (e.g. regulate HR, movement of food through GI tract)
Describe how the hypothalamus functions with hormone production
releases hormones into capillary network –> carried to anterior pituitary –> stimulate/inhibit secretion of ant pit hormones
- cell bodies in paraventricular and supraoptic nuclei produce ADH/oxytocin
Describe how the hypothalamus functions in the regulation of emotional and behavioural patterns
with limbic system, participates in expression of pain, pleasure, rage, sexual arousal, aggression
Describe how the hypothalamus functions in the regulation of eating/drinking
contains thirst, feeding, and satiety centers
certain cells stimulated by increasing osmotic pressure of ECF and cause thirst sensation –> drinking H2O restores normal osmotic pressure
Describe how the hypothalamus functions in the control of body temp
ANS stimulate vasodilation/vasoconstriction to release/retain heat when temp of blood flowing through hypothalamus is too hot/low
Where is the epithalamus found and what does it contain?
- sup and post to the thalamus
- contains the pineal gland and habenular nuclei
What is the function of the pineal gland?
- secretes melatonin during darkness
- promotes sleepiness, sets biol clock
- pea-sized endocrine gland
What is the function of the habenular nuclei?
- involved in olfaction, particularly emo responses to odours
What are circumventricular organs (CVOs) ?
structures that lie w/i the 3rd ventricle and lack a BBB
- includes part of the hypothalamus, pineal gland, pituitary gland, and other nearby structures
What is the function of CVOs?
- monitor chem changes in blood to coordinate homeostatic activities of the endocrine and nervous systems (e.g. BP, fluid balance)
What does the cerebrum consist of?
- outer cerebral cortex (grey matter)
- inner cerebral white matter
- deep grey matter nuclei
- gyri (folds of cortex)
- fissures (deep grooves bt folds)
- sulci (shallow grooves bt folds)
How are the cerebral hemispheres organized and what do they do?
2 hemispheres divided into 4 lobes (frontal, parietal, occipital, temporal)
- each hem receives sensory input and generates motor output to opposite side of body
