produced in the paraventricular nucleus of the hypothalamus; transmitted to posterior pituitary; released from posterior pituitary into bloodstream
oxytocin release in the brain
neurons of the posterior pituitary innervate the nucleus accumbens; dendritic vs. axonal release not determined
production of vasopressin
produced in the hypothalamus; transmitted to the posterior pituitary; affects the amygdala
sexual dimorphism of vasopressin
vasopressin = testosterone-dependent; much more widespread in male brain; produces male-typical behaviors & pair-bonding in males
effects of oxytocin on social bonding
OTKO mice have social amnesia; injection of OT rescues
prairie vs. meadow voles
prairie voles = monogomous; have more oxytocin receptors in brain; meadow voles = promiscuous
V1AR
differences in vasopressin receptor gene expression are correlated with differences in social behavior; long sattelite regions of this gene are associated with increased social attachment
alpha-melanocyte stimulating hormone
stimulates oxytocin release; can pass through the blood-brain barrier
limbic system
includes the hippocampus; fornix; fimbria; dentate gyrus; amygdala; parahippocampal gyrus; cingulate gyrus; subcallosal gyrus
fornix
C-shaped structure in the limbic system that carries information from the hypothalamus to the mammilary bodies and septal nuclei
mammillary bodies
small round bodies; part of the limbic system; involved in processing of memories
episodic memory
also called declarative memory; long-term memory; involves the hippocampus and medial temporal lobe
working memory
short-term memory; involves the dorsolateral prefrontal cortex
emotional memory
involves the amygdala
procedural memory
motor memory; involves the basal ganglia
retrograde amnesia
loss of episodic memories
antereograde amnesia
inability to form new memories
non-associative learning
includes habituation and sensitization
associative learning
classical and operant conditioning
patient H.M.
landmark patient in the understanding of memory disorders; partial removal of temporal lobes resulted in severe retrograde amnesia
roles of the hippocampus
episodic memory; regulation of HPA axis (involved in stress response)
limbic loop
limbic system -> activation of ventral striatum -> inhibition of ventral pallidum ->less inhibition of thalamus -> activation of limbic system
posterior hypothalamus
stimulation activates the sympathetic nervous system
anterior hypothalamus
stimulation activates the parasympathetic nervous system
function of the hypothalamus
regulatory; maintenance of homeostasis; compares sensory information with set points from the cerebral cortex
neuropeptides
small neurotransmitters produced within the nuclei of the hypothalamus; act on the anterior pituitary
infundibulum
connects hypothalamus with the pituitary gland
suprachiasmatic nucleus
regulates circadian rhythm; found within the hypothalamus
posterior pituitary
neurons from the hypothalamus project directly to the posterior pituitary to induce the release of hormones (two-tiered response)
anterior pituitary
neuropeptides produced in the hypothalamus act up the anterior pituitary to induce the release of hormones (three-tiered response)
magnocellular neurons of the hypothalamus
produce oxytocin and/or vasopressin; project to posterior pituitar for hormonal release; on kidney & uterus & mammary gland
parvocellular neurons of the hypothalamus
act on anterior pituitary to release trophic hormones
organization of the somatic motor system
somatic motor neurons project directly to the muscle of innervation
organization of the autonomic motor system
preganglionic motor neurons project to autonomic ganglia; unmyelinated postganglionic motor neurons project to the muscle of innervation
distinguishing features of sympathetic vs. parasympathetic nervous system
location of preganglionic neuronal bodies; neurotransmitter released from postganglionic neurons; diffuse vs. targeted outflow
adrenal medulla
located inside adrenal gland; innervated primarily by cholinergic preganglionic neurons of the sympathetic nervous system; activation evokes secretion of adrenaline/noradrenaline into circulation
neurotransmitter of sympathetic ANS
primarily epinephrine and norepinephrine
neurotransmitter of parasympathetic ANS
primarily acetylcholine
cholinergic receptors
receptor for acetylcholine; primarily found on organs innervated by the parasympathetic nervous system; include M1 and M2 receptors; binding generally leads to smooth muscle contraction
adrenergic receptors
G-protein coupled receptors that are the targets for catecholemines; primarily found on organs innervated by the sympathetic nervous system; include alpha-1 and beta-1 and beta-2 receptors; binding generally leads to smooth muscle relaxation
enteric nervous system
intrinsic to the gastrointestinal tract; not directly controlled by the CNS; modulated by ANS modulation (primarily parasympathetic)