7A Flashcards
(191 cards)
sensory neurons
afferent neurons, transmit info from receptors to spinal cord and brain
motor neurons
efferent neurons, transmit motor info from brain and spinal cords to muscles and glands
interneurons
found between other neurons, most numerous. predominately in brain and spinal cord, deal with reflexive behavior
reflex arcs
neural circuits control reflexive behavior, step on nail, foot detects pain and pain signal transmitted by sensory neurons to spinal cord, then interneurons bypass brain and send signals to muscles of leg directly
central nervous system (CNS)
brain & spinal cord
peripheral nervous system (PNS)
made up of nerve tissue and fibers outside the brain and spinal cord. i.e. 12 pairs of cranial nerves and 31 pairs of spinal nerves. connects cns to rest of body, subdivided into somatic and autonomic
somatic nervous system
consists of sensory and motor neurons distributed throughout the skin, joints, and muscles
autonomic nervous system
generally regulates heartbeat, respiration, digestion, glandular secretions, involuntary muscles assc with internal organs and glands
ANS Subdivisions
parasympathetic and sympathetic nervous system
parasympathetic
conserve energy, resting/sleeping states, reduces heart rate/constrict bronchi, increase peristalsis/exocrine secretions, acetylcholine is NT responsible
sympathetic
activated by stress, inc. heart rate, blood to muscles of locomotion, inc. blood glucose, dec. digestion/peristalsis, dilate eyes, epinephrine release
meninges
brain covered with thick sheath of connective tissue, protect brain, keep it anchored with skull, resorb CSF.
3 layers of meninges
dura mater, arachnoid mater, pia mater
dura mater
outermost layer
arachnoid mater
middle layer
pia mater
innermost layer, closest to brain
cerebrospinal fluid
aqueous soln in which brain and spinal cord rest, produced by specialized cells that line ventricles (internal cavities) of brain
three basic brain subdivisions
hindbrain, midbrain, forebrain
brainstem
hindbrain + midbrain, most primitive region of the brain
limbic system
group of neural structures primarily associated with emotion and memory. aggression, fear, pleasure, and pain are related to limbic system
cerebral cortex
most recent evolutionary development of human brain, outer covering of cerebral hemispheres, associated with language processing to problem solving, impulse control, long term planning
forebrain structures (5)
cerebral cortex, basal ganglia, limbic, thalamus, hypothalamus
forebrain function (5 sections)
complex perceptual, cog, behavioral processes/ movement/ emotion, memory/ sensory relay station/ hunger, thirst, emotion
midbrain structures (2)
inferior and superior colliculi