Motivation Flashcards
suprachiasmatic nucleus
ganglion cells send signals to this to determine if it is light out
- lesions lead to disrupting sleep patterns
melatonin
pineal body secretes melatonin from SCN projections
- induces fatigue and sedation
- sleeping pills include this but do not form a tolerance
slow wave sleep
- 4 stages, progressively larger amplitudes
- cortical lobes detach during slow wave
- mild muscle tone
- no dreams
REM sleep
- 5th stage
- awake EEG
- rapid eye movements
- muscle tone lost, if you have lesion= can lead to sleep walking
cerveau isole
isolation from the forebrain and brainstem leads to permanent sleep
- brainstem wakes up brain
reticular system
after a man was stimulated by electricity in the vagus nerve continuously, it activate reticular system and cortex
raphe nuclei
electrical stimulation of this triggers sleep
- contains serotonin NT
lesion= can lead to temporary abolishment of sleep
basal forebrain GABA
promotes sleep, inhibiting arousal neurons
tubermammillary nucleus
arousal neurons are found here
Lateral hypothalamus
hypocretin in this promotes waking
Orexin/hypocretin
promote waking, inhibited in narcalepsy
PGO spike
pontine, geniculate, and occipital cortex= generate eye movement
hypovolemic thirst
- low blood volume, water deprivation, perspiration (heat thirst), injury thirst
process of hypovolemic thirst
- drop in blood pressure is detected
- Renin secretion by kidneys (neuroendocrine relex)
- Angiotensin II produced in blood
- Angiotensin II enters brain and causes thirst
- Angiotensin II enters Circumventricular organs (places without blood brain barrier)
-Hypothalamus and OVLT
Bp.R.Pr.B.Co
hyperosmotic thirst
- water deprivation, salty foods
- hypertonic extracellular fluid pull water from neurons
hunger
- lateral hypothalamus is center of hunger functions: - monitors body fuels - taste pleasure - incentive wanting lesions- aphagia (no eating)
ventromedial hypothalamus
lesions
- hyperphagia ( overeating)
- enhanced metabolism: hyperinsulinemia leads to storage of more fat
hypothalamic peptides
- satiety hormones (leptin)
- hunger (ghrelin)
leptin
without this, become obese
ghrelin
promotes eating, stomach hormone secreted before eating
POMC-CART neurons
satiety
- stimulated and then produce leptin
NPY-AGRP neurons
Hunger
- ghrelin stimulates
norepinephrine pathway
lesion= hyperphagia agonists= diet drugs
serotonin pathway
supresses feeding
-
neuropeptide pathway
triggers feeding
- inhibited by leptin
estrogen
can become masculinized by abundance of estrogen in bloodstream
testosterone
can cross the blood brain barrier and turned into estrogen
alpha feto protein
binds to estrogen causing it to not cross blood brain barrier
freemartin
female with male in utero can experience masculinization
medial anterior hypothalamus
lesion
- disrupt lordosis in genetic females
stimulation: leads to lordosis
preoptic area
lesion
- disrupts male sexual behavior
stimulation
- triggers male sexual behavior
preoptic INAH-3
- larger in men
- larger in heterosexuals
septum
lesions
- septal rage
- stop septal rage with adding amygdala lesion as well
stimulation= rabies
amygdala
lesion
- septal lesions disinhibit the amygdala
kluver bucy syndrom
especially aggressive
- large lesion of temporal lobe led to no aggression at all
hyperorality
pick things up and put them in their mouth
hypersexuality
- some would show sexual behavior to females in and out of estrus
ACTH secretion
pituitary trigger for stress axis
CRF secretion
brain trigger, glucorticoid hormones
