GRADED A+ 2025/2026
action potential - a neural impulse; a brief electrical charge that provides basis for
sending info along axon
--Na+ rush in through sodium channels, inside becomes positive from charged ions
depolarization - The process during the action potential when sodium is rushing into the
cell causing the interior to become more positive and K+ moves outside of potassium
gates causing resting value again
all or none - once action potential is triggered, it is propagated without decrement to end
of fiber
--ms by ms sum of all signals determines whether neuron will fire or not
synapse - the junction between terminal button of one neuron and membrane (soma or
dendrites) of another
synaptic gap - space between the axon terminal of one neuron and the receptors of the
next neuron, when action potential occurs reaches terminal button: vesicles release
neurotransmitter into synaptic cleft
neurotransmitters - travel across synaptic gap, bind to receptor sites on receiving
neuron, effect might be excitatory or inhibitory
ligands - bind to postsynaptic membrane at binding sites, can be a natural body
produced chemical (neurotransmitter) or other chem like medication or poison
reuptake - ransporters located in thepre-synaptic membrane transport themolecules of
neurotransmitter backinto the cytoplasm
SSRI - block reuptake of serotonin,making more of it available at thesynaptic gap and
increasingserotonergic activity
enzymatic deactivation - destruction of a neurotransmitter by an enzymeafter its release
neurogenesis - production of new neurons, adult brain can divide and produce new
neurons mainly in hippocampus, olfactory bulb, and amygdala
--new synaptic connections between neurons
--dendritic branching
Central Nervous System (CNS) - brain and spinal cord
Peripheral Nervous System (PNS) - the sensory and motor neurons that connect the
central nervous system (CNS) to the rest of the body.
, sympathetic nervous system - Division of the autonomic nervous system that controls
functions that accompany arousal and expenditure of energy (increased heart rate, rise
in blood sugar level, piloerection("goosebumps"))
adrenal medulla - secretes epinephrine and norepinephrine
parasympathetic nervous system - Division of the autonomic nervous system that
controls functions that occur during a relaxed state; secretes acetylcholine
--Supports activities involved with increases in the body's supply ofstored energy, such
as salivation, gastric and intestinal motility
neuroanatomical orientations - anterior, posterior, dorsal, ventral, lateral, medial
anterior - located near ortoward the front
posterior - near or toward back
dorsal - in a direction towardthe top of the head or the bac
ventral - in a direction towardthe bottom of the skull or thefront surface of the body
lateral - toward the side of thebody, away from the middle
medial - toward the middle ofthe body, away from the side
coronal or frontal section - slice through brain parallel to forehead
sagittal or lateral section - slice through brain perpendicular to ground and parallel to
temporal lobes
transverse or axial section - slice through brain parallel to ground
cerebral cortex - outmost layer of grey matter of cerebral hemisphere about 3 mm,
consists of glia and cell bodies
neocortex - Part of the cerebral cortex; generally thought to be most closely associated
with problem solving and behavioral flexibility. In mammals, the neocortex covers
virtually the entire surface of the forebrain.
limbic cortex - phylogenetically old cortex, located at the medial edge of the cerebral
hemispheres; part of the limbic system
frontal lobe - involved in speaking and muscle movements and in making plans and
judgements, and emotional control
primary motor cortex - voluntary movement