Chemical Control of Behavior Flashcards
What is homeostasis?
maintenance of the body’s internal environment within a certain range
What are the 3 functional structures of the hypothalamus?
Lateral hypothalamus, medial ventral zone, periventricular zone
The lateral hypothalamus controls _______; conversely the ventromedial hypothalamus controls ______
hunger; satiety
What happens if the ventromedial hypothalamus is lesioned?
excessive eating
What function does the suprachiasmatic nucleus in the periventricular zone have?
Establishes Circadian Rhythms with respect to the light/dark cycle
How do cortisol levels in the body change during the day?
Rise just before waking up, then drop steadily throughout the day
Which part of the pituitary is actually a gland?
anterior
Which neurohormones do magnocellular secretory cells secrete?
oxytocin and vasopressin
When is oxytocin highest?
intimate/sexual behavior, pregnancy
What is another name for vasopressin?
antidiuretic hormone
What is vasopressin’s function and how does it perform said function?
it regulated blood volume and salt concentration; causes kidneys to release renin, which acts on angiotensin I in the liver, which acts on angiotensin II, which raises blood pressure and causes thirst when detected by the subfornical organ in the hypothalamus
What part of the hypothalamus detects angiotensin II?
subfornical organ
The anterior pituitary controls the _____ system.
endocrine
Parvocellular neurosecretory cells communicate with the anterior pituitary via ______
hypothalamo-pituitary portal circulation/local blood vessels
Parvocellular neurosecretory cells release hypophysiotropic hormones, which bind to receptors on the anterior pituitary to
secrete or halt secretion of hormones into blood
Which hormone released by the parvocellular neurosecretory cells causes the release of cortisol?
CRH (corticotropin releasing hormone)
What does the somatic nervous system control?
skeletal muscles
Preganglionic neurons in the somatic and autonomic nervous system release which neurotransmitter?
acetylcholine
The sympathetic nervous system activates the body’s _______ response. The parasympathetic nervous system activates the _______ response.
fight or flight/emergency; rest and digest/relaxation
Postganglionic cells in the sympathetic NS release ______; those in the parasympathetic NS release _____
norepinephrine; acetylcholine
Acetylcholine released by postganglionic cells in the parasympathetic NS bind to ______ receptors.
muscarinic
Sympathomimetic drugs enhance ______ and reduce _____ action.
norepinephrine; muscarinic
Parasympathomimetic drugs mimic the activation of the ______ nervous system.
parasympathetic
The enteric division of the autonomic NS monitors and controls _______ functions.
gastrointestinal
Why is negative feedback important to consider when taking prescription steroids?
The body will think cortisol levels are too high and inhibit the release of it.
The nucleus of the solitary tract integrates information from ______ and coordinates output to ________
internal organs; autonomic brain stem nuclei
What are the two major areas of cell body concentration in the dopaminergic system?
Substantia nigra, ventral tegmental area
What does the ventral tegmental area control?
reward, reinforcement and appetitive behaviour
Diffuse modulatory systems perform _____ functions, and have diverse and widespread effects on the brain.
regulatory
The core of the noradrenergic system is in the ______
Locus Coeruleus
The cell bodies of the serotonergic are found in the ______
Raphe nuclei
Psychoactive drugs affect the _____ system; stimulant drugs affect _______ systems by blocking reuptake of the neurotransmitters.
serotonergic; catecholaminergic
