II) Nerve Impulse
A) All or None
1) Once triggered beyond
a point neural impulse will fire
B) Resting Potential
1) The inside of the
cell is negatively charged (-70 millivolts) while the outside of the
cell is positive
III) Synapse
A) Tiny gap between an axon terminal
& another neuron (or
specialized
cell)
B) Firing neurons release neurotransmitters
that cross the synapse
C) The neurotransmitter binds to
the receptor site on the target cell
D) Ion gates open
IV) Neurotransmitters
A) After crossing the synapse,
the neurotransmitter is reuptaken or
degraded
B) There are more than 40 known
types
C) Different neurotransmitters
have different effects
D) Drugs, neural diseases often
affect neurotransmitters
V) Major Neurotransmitters
A) Acetylcholine (ACh): important
for learning, memory, muscle
movement
B) Serotonin (5-HT): influences
mood and regulates food intake
C) Dopamine (DA): important
to movement and to frontal lobe activity
D) GABA: important in inhibiting
neural activity
E) Norepinephrine (NE): maintains
alertness & wakefulness
F) Endorphins: regulate firing
of pain neurons
VI) Agonistic Drugs
A) Increase synthesis of neurotransmitter
B) Increase release of neurotransmitter
C) Activate receptors, imitate
neurotransmitter
D) Inhibit reuptake of neurotransmitter
VII) Antagonistic Drugs
A) Interfere with release of neurotransmitter
B) Occupy and block neurotransmitter
sites
C) Cause neurotransmitter loss
from vesicles
VII) Major Structures of the Brain
A) The Hindbrain
1) Medulla: Regulates
heart rate & breathing
2) Pons: Links to cerebellum,
affects arousal, dreaming
3) Cerebellum: Balance,
coordination, movement
4) Reticular Formation
(deep inside): Controls arousal, waking, sleeping
B) The Midbrain
1) In mammals, little
more than a relay station
2) Coordinates signals
between hindbrain & forebrain
C) The Forebrain
1) Thalamus: A critical
relay station to the higher brain centers
2) Hypothalamus: Controls
appetites and homeostasis
3) Pituitary gland: Part
of the endocrine system-- connects to the hypothalamus,
releases critical hormones
4) Optic Nerve: Extends
the brain into the retina in each eye
5) Corpus Callosum: Connects
hemispheres of the cortex
6) Limbic System:
a) The hippocampus (memory)
b) The amygdala (emotional expression)
XI) Lobes of the Brain
A) Temporal Lobes: Contain the
auditory cortex, Wernicke's area,
associations
related to auditory stimuli
B) Occipital Lobes: Contain
the visual cortex, associations related to
visual
stimuli
C) Parietal Lobes: Contain
the somatosensory cortex, associations
related
to spatial orientation
D) Frontal Lobes: Contain
controls for speech production, thinking,
planning,
reasoning, impulse control, motivation
1) Example: After Phineas Gage's frontal lobes were destroyed in
a blasting
accident, his ability to plan, limit impulses, and reason were destroyed.
XII) Related
Links