Chapter 2 Flashcards
neuroplasticity
the brain’s ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience
neuron
a nerve cell. basic building block of nervous system
cell body (neuron)
part of the neuron that contains the nucleus
dendrites
branching extensions of a neuron which receive and integrate messages, conducting impulses towards the body
axon
long segmented neuron extension that passes messages through it’s branches (terminal branches) to other neurons or to muscles or glands
myelin
fatty coating on some neuron’s axons which insulates + speeds up the impulses
glial cells
nervous system cells that support, nourish, and protect neurons. also play a role in learning, thinking, and memory
action potentential
a brief electrical charge that travels down an axon
excitatory neural signals
pushing the accelerator
inhibitory neural signals
pushing the breaks
threshold (relating to neurall signaling)
level of stimulation required to produce a neural impulse
refractory period
a brief resting pause that occurs after a neuron as fired. action potentials cannot occur when a neuron is it its refractory period
synapse
junction between the tip of an axon from one neuron and the dendrites of another
synaptic cleft
actual space in synapse
neurotransmitter
chemical messenger that crosses the synaptic cleft. when released by sending neuron, they travel across synapse and bind to receptor sites on receiving neuron.
reuptake
a neurotransmitter’s reabsorption by the sending neuron
endorphines
natural opiate-like neurotransmitters in the body linked to pain and pleasure
“morphine within”
agonist
a molecule that increases a neurotransmitter’s action
the nervous system
the body’s fast, electrochemical communication network consisting of all nerve cells
antagonist
a molecule that inhibits or blocks a neurotransmitter’s action
central nervous system (CNS)
spine + brain
decision making center
peripheral nervous system (PNS)
nerves that connect everything else to the CNS
nerves
bundled axons that form neural cables connecting CNS with muscles, glands, and sensory organs
sensory (afferent) neurons
cary incoming info from PMS to CNS
motor (efferent) neurons
cary outgoing info from CNS to muscles and glands
interneurons
neurons in think in spine that connect between other neurons and have something to do with reflexes?
somatic nervous system (SNS)
controls voluntary movement of skeletal muscles
interneurons
found in CNS only. communicate internally and process information between the sensory inputs and motor outputs
autonomic nervous system (ANS)
controls glands + internal organs (usually operates autonomously)
sympathetic nervous system
a subdivision of the ANS
arouses and increases energy
parasympathetic nervous system
a subdivision of the ANS
calms + conserves energy, returning the body to homeostasis
spinal chord
two-way information pathway connecting PNS and CNS
ascending fibers bring sensory input to brain, descending fibers send back motor-control impulses
reflex
a simple, automatic response to sensory stimuli (knee jerk)
often one single neuron from spinal chord to area of stimuli for fast reaction time
endocrine system
the body’s “slow” chemical communication system: glands and fatty tissues secrete hormones into bloodstream
hormone
chemical messenger that is manufactured by endocrine glands. travel through the bloodstream + affect other tissue(s)
adrenal glads
pair of endocrine glads atop the kidneys which secrete epinephrine and adrenaline causing body arousal during stressful times (feeling often lingers)
pituitary glad
most influential gland, master gland controlled by the hypothalamus. regulates growth + controls other glands
lesion (brain)
tissue destruction (brain lesions can be natural or experimentally caused)
electroencephalogram (EEG)
amplified recording of electrical activity sweeping across the brain’s surface (cortex)
magnetoencephalography (MEG)
brain-imaging technique measuring magnetic fields from the brain’s neural activity
position emmission tomography (PET)
a technique for detecting brain activity by displaying where a radioactive form of glucose goes while brain performs a task
magnetic resonance imaging (MRI)
technique that uses magnetic fields and radio waves to produce computer-generated images of soft tissue, showing brain anatomy
functional MRI (fMRI)
technique for revealing bloodflow and therefore brain activity by comparing succesive MRI scans. shows brain structure and function
brainstem
oldest part of brain. begins at top of spinal chord where it enters the skull and includes the medulla and pons
medulla
base of the brainstem. controls heartbeat + breathing
thallamus
brain’s sensory control center. directs messages to sensory receiving areas in cortex + transmits replies to medulla and cerebellum
reticular formation
the nerve network that travels through the brainstem into the thalamus. filters information and plans an important role in controlling arousal
cerebellum
at rear of brainstem. processes sensory input coordinating movement output and balance and enables non-verbal (muscle) learning + memory
“little brain”
limbic system
neural system consisting of the amygdala, hypothallamus, and hippocampus. associated with emotion and drives (hormones)
amygdala
two lima-bean sized neural clusters in limbic system. linked to emotion (aggression and fear)
hypocampus
neural center located in limbic system. helps process explicit (conscious) memories for storage (facts and events)
hypothallamus
neural structure directly below thalamus. directs maintenance activities (eating, drinking, body temp). helps govern endocrine system through pituitary glad (also linked with emotion and reward)
cerebral cortex
intricate fabric of interconnected neural cells covering the cerebral hemispheres (surface of brain). the body’s ultimate control and informational processing center
frontal lobes
portion of brain directly behind forehead. involved in making plans + judgements, inhibition, risk judgement
parietal lobes
portion of brain at top of the head and toward the rear. receives sensory input for touch and body positioning
occipital lobes
lobe at very back of head. facial recognition and memory.
temporal lobes
section of brain roughly right above/at ear level. includes the auditory areas, each receiving information primarily from the opposite ear
motor cortex
strip of cortex at rear of frontal lobe and anterior to the central sulcus. controls voluntary movement.
somatosensory cortex
strip of brain at front of the parietal lobe and immediately posterior to the central sulcus
processes touch, pain, etc
association areas
areas of cerebral cortex that are NOT involved in primary motor or sensory functions. rather they are involved in higher mental functions (learning, thinking, etc)
neurogenesis
formation of new neurons
corpus callosum
large band of neural fibers connecting the two brain hemispheres and passing information between them
split brain
condition resulting from surgery which separates the right and left hemispheres by cutting the corpus callosum
performing perceptual tasks = increased brain activity on BLANK side
increased brain activity in RIGHT side
performing math/calculations = increased brain activity on BLANK side
increased brain activity in LEFT side
boca’s area
in middle(ish) of frontal lobe on the LEFT hemisphere. responsible for speech PRODUCTION
BOCA = MOUTH = SPEACH PRODUCTION
wernick’s area
in middle of LEFT temporal lobe directly below the lateral sulcus. responsible for speech COMPREHENSION
