Biology and Behaviors

sensory (afferent neurons)

motor (efferent) neurons

interneurons

reflex arcs

ability of interneurons in spinal cord to relay info to source of stimuli while also routing it to the brain

central nervous system (CNS)

brain and spinal cord

peripheral nervous system (PNS)

most cranial and spinal nerves

PNS divisions

somatic (voluntary) and autonomic (automatic)

autonomic system divisions

parasympathetic (rest-and-digest) and sympathetic (fight-or-flight)

three subdivisions of the brain

hindbrain, midbrain, forebrain

hindbrain contains

cerebellum, medulla oblongata, and reticular formation

midbrain contains

inferior and superior colliculi

forebrain contains

thalamus, hypothalamus, basal ganglia, limbic system and cerebral cortex

methods of studying the brain

lesions, electrical stimulation and activity recording (EEG), and regional cerebral blood flow

thalamus

relay station for sensory info

hypothalamus

maintains homeostasis and integrates with the endocrine system the hypophyseal portal system and that connects it to the anterior pituitary

basal ganglia

smoothen movements and help maintain postural stability

limbic system

contains the septal nuclei, amygdala and hippocampus, controls emotion and memory

septal nuclei

involved with feelings of pleasure, pleasure-seeking behavior, and addition

amygdala 

controls fear and aggression

hippocampus

consolidates memories and communicates with other parts of the limbic system through an extension called the fornix

divisions of cerebral cortex

frontal, parietal, occipital and temporal

frontal lobe

controls executive function, impulse control, long-term planning, motor function, and speech production

parietal lobe

controls sensations of touch, pressure, temperature and pain; spatial processing; orientation; and manipulation

occipital lobe

controls visual processing

temporal lobe

controls sound processing, speech perception, memory and emotion

division of brain

left hem and right hem

• left: for language

neurotransmitters

released by neurons and carry a signal to another neuron or effector (a muscle fiber or gland)

types of neurotransmitters

acetylcholine, dopamine, endorphins/enkephalins, epinephrine/norepinephrine, GABA/glycine, glutamate, serotonin

acetylchonile

used by somatic NS (to move muscles), parasympathetic NS, and CNS (for alertness)

dopamine

maintains smooth movements and steady posture

endorphins and enkephalins

natural painkillers

epinephrine and norepinephrine

maintain wakefulness and alertness and mediate fight or flight responses

GABA (gamma-aminobutyric acid) and glycine

brain “stabilizers”

glutamate

excitatory neurotransmitter in the brain

serotonin

modulates mood, sleep patterns, eating patters, and dreaming

cortisol

stress hormone released by the adrenal cortex

testosterone and estrogen

mediate libido; both released by adrenal gland

epinephrine and norepinephrine (endocrine system)

released by adrenal medulla and cause physiological changes associated with sympathetic nervous system