Key Terms for Endocrine and Nervous Systems

Acetylcholine

NT; chemical means by which neurons communicate with muscles; also involved with memory, learning, and general intellectual functioning. deficiency in those with Alzenheimer’s

Serotonin

NT; associated with “calm” and involved with sleep, sensory perception, mood, and emotional state

Norepinephrine

NT/hormone; produced by adrenal gland and in brainstem, triggers fight or flight response

Glutamate

NT; excitatory neurotransmitter involved in learning, memory, sensory processes

GABA

NT; inhibitory neurotransmitter that regulates the level of neural activity in the brain—alcohol increases presence of this short-term but lowers receptors long-term

Endorphins

NT; excitatory released in response to pain or stress and create positive mood/pain relief in response to exercise

Dopamine

NT; inhibitor involved with movement, attention, learning, and associated with reward pathways; deficiency in those with Parkinson’s

Dopamine pathway

in the mesolimbic dopamine pathway (in limbic system): dopamine first activated in ventral tegmental area, then projected to nucleus accumbens

in mesocorticol dopamine pathway (in cerebral cortex): activation of nucleus accumbens is projected up to prefrontal cortex, which understands the reward and plans further

Dopamine and ADHD

higher levels of dopamine transporter → overactive reuptake of dopamine, struggle with motivation

Brain processes of nicotine use

nicotine bonds to nicotinic receptors to facilitate release of acetylcholine, dopamine, epinephrine/norepinephrine

long-term use results in desensitization of nicotinic acetylcholine receptors & increase in number of receptors

Brain processes of alcohol use

short-term: GABA agonist, binds to GABA receptors and facilitates release; reduces glutamate functioning

long-term: brain compensates to restore homeostasis by decreasing baseline GABA function and increasing baseline glutamate; inhibits function of frontal lobe

Brain processes of psilocybin

serotonin agonist (desensitization and down-regulation of receptors), increases dopamine activity, increases glutamate through serotonin

Difference between hormone and neuron signals

neurons: electrical signal travels along an axon → chemical signals (NTs) over short distances at a synapse

hormones: chemical signals over long distances after being released into the bloodstream; brain triggers release of hormones that trigger glands to release other hormones

Hypothalamus in the endocrine system

links endocrine and nervous systems by regulating pituitary gland; secretes hormones that are stored in posterior pituitary that are later released

Pineal gland

produces melatonin to regulate sleep/wake cycle

Pituitary gland

regulates activities of several other glands; produces HGH, prolactin, oxytocin

Thyroid gland

controls body metabolism rate

Adrenal gland

produces epinephrine and norepinephrine; involved in stress/fight/flight response

Pancreas

regulates blood sugar and insulin levels; involved in hunger

Gonads

regulate sexual development and reproduction; ovaries secrete estrogen and progesterone while testes secrete testosterone

Prolactin

secreted by pituitary gland; responsible for lactation and some breast tissue development; elevated when pregnant/breastfeeding

Oxytocin

produced by hypothalamus and released by pituitary gland; involved in reproduction, social motivation, and social behavior

Epinephrine (adrenaline)

produced by adrenal gland’ increases rate of blood circulation, breathing, and carbohydrate metabolism

Cortisol

secreted by adrenal gland; regulates stress response, metabolism, and blood sugar by triggering glucose release from liver

Melatonin

secreted by pituitary gland; helps with timing circadian rhythms and sleep

Insulin

secreted by pancreas; facilitates uptake of glucose from bloodstream into cells, promotes storage of glucose in liver and muscles, inhibits production of glucose and breakdown of glycogen

Progesterone

secreted by ovaries; prepares endometrium for fertilized egg and supports menstruation and early pregnancy