steps of Hypothalamic hormones journey
1. hypothalamic hormones are relaesed into a capillary network
2. hormones travel down a "portal" vein in the pituatary stalk
3. hormones excite or inhibit other hormones of the anterior pituatary to be released into bloodstream
- *Hypothalamus-pituatary gonadal axis
Where do we get the Y chromosome from?
We all have a _________, what dictates who has potential to be a male?
primordial, and the prescence of a Y chromosome
Whats responsible masculinizing the hypothalamus?
Male pathways in the brain (2)
-lateral tegmental field
-medial preoptic area
Female pathways in the brain (2)
Female rats have "proceptive" behaviors (flirting actions), what triggers it? (3)
*Progestorone seems to play an especially strong role in female procetive behaviors
3 components to the motivational side of sexual behavior
- drive to engage in sexual behavior
-anticipation of a sexual encounter
-reward associated with sexual behavior
(motivational component in sexual beahvior in rats) Female and male rats develop_______ for sexual encounters.
conditioned place preferences
Which NT is released in response to the delivery of rewarding stimuli?
ex) food, drugs, sex
-The VTA and Sn of rats and oher animals will activate when they do work to get satisfaction
-dopamine release in the nucleus accumbens is associated with food and other rewards
Dopamine levels and sexual behavior
dopamine levels are high when engaging in sexual behavior but then drop when the interest is gone
(females want soemting different) female sexual behavior
-they engage in appraoch and avoidance behaviors directed toward male to pace the rate of copulation which will result a pattern of vagincervical stimulation that triggers a neuroendocrine reflex important for pregnancy
-was a responsible, respected contruction worker for railroad
-after damage to the frontal lobe, he became a different person in his emotions.
Areas of our brains appear to play a particularly...
important role in emotion
Experiment of Bard
-removed a cats cortex which resulted in overly aggressive behavior from the cat that wasnt being directed to anyone
Hypothalamus appears to be critical for ________ and the role of the _________ is to inhibit these reponses as well as direct them
aggressive behaviors, cortex
*prove: when they didnt cut the hypothalamus they didnt have sham rage but when they did they did have sham rage
Electrical stimulation of specific regions of_________ leads to the expression of aspects of emotion.
hypothalamus (medial hypothalamus)
*they trigger "affective attack"
Dr James Paypez work
-proposed a circuit
-emotions are expressed by inputs of a variety of structures on hypothalamus
-emotions are experienced by inputs of a variety of structures on the cortex
*structures involved in processing of emotion, LIMBIC SYSTEM
Where did stress come from? and what was it referred to as?
Hans Seyle, "the weight of all the wear and tear caused by life"
when do we experience stress?
when the body is exposed to harm or threat
Seyle's 3 phases "General adaption syndrome"
(seyles 3 pahses GAS) 1. Alarm reaction
alarm reaction to the stressor is the initial response
(seyles 3 pahses GAS) 2. Adaptation stage
- activation of appropriate response systems to bring the body back to a normal state.
(seyles 3 pahses GAS) 3. Exhaustion phase
in response to prolonged stress leads to increased susceptibility to disease
Stressful stimuli activate the_________ which in turn activates_______ to promote_________
hypothalamus, adrenal glands, secretions
2 ways in which hypothalamus activates the adrenals
Where are the adrenal glands located?
just above the kidneys
2 portions of the adrenal glands
(portions of adrenal glands) Cortex
secretes hormones: cortisol, androgens, and estrogens
(portions of adrenal glands) Medulla
secretes: norepinephrine and epinephrine
(ways of activating adrenals) Hormonal response steps (3)
-hypothalamus releases cortocotropin-releasing hormone (CRH)
-CRH stimulates the release of adrenocorticotropic hormone (ACTH) from cells in anterior pit. gland
-ACTH stimulates the adrenal cortex to release cortisol(steroid hormone)
negative feed back occurs to...
(ways of activating adrenals) Neural response steps (2)
-autonomic nervous system
-neurons of the hypothalamus project to ganglion of sympathetic nervous system which then innervate the adrenal medulla to cause the release of norepinephrine and epinephrine
Stress activates both _______ and ________ responses
neural , hormone
(Results of activation of adrenals) Cortisol (3)
-increases blood pressure
-increases blood sugar level
-suppresses immune function...immune response causes inflammation so cortisol suppresses inflamation
(Results of activation of adrenals) Epinephrine and Norepinephrine (2)
- increase heart rate
-increase blood pressure
(long term stress) Holding position in dominance hierarchy is stressful
- -they are always watchign their back for challengers
- *but get most/all the resources available
(social hierarchy) Chronic social stress results (3)
- -stress suppreses testosterone levels
- *subordinates have testes reduced in size
-shorter life span
-lower body weight