Chapter 2 Flashcards
a neuron’s often bushy, branching extensions that receive messages and conduct impulses toward the cell body
Dendrites
the neuron extension that passes messages through its branches to other neurons or to muscles or glands
axon
the cell’s life-support center (of a neuron)
Cell Body
a neural impulse; a brief electrical charge that travels down an axon.
Action Potential
a fatty tissue layer segmentally encasing the axons of some neurons; enables vastly greater transmission speed as neural impulses hop from one node to the next
Myelin Sheath
a part of the neuron that forms junctions with other cells
Terminal branches of axon
the scientific study of the links between biological (genetic, neural, hormonal) and psychological processes.
Biological Psychology
a nerve cell; the basic building block of the nervous system
neuron
cells in the nervous system that support, nourish, and protect neurons; they may also play a role in learning, thinking, and memory
glial cells(glia)
the level of stimulation required to trigger a neural impulse
threshold
a brief resting pause that occurs after a neuron has fired; subsequent action potentials cannot occur until the axon returns to its resting state.
refractory period
a neuron’s reaction of either firing (with a full-strength response) or not firing
all-or-none response
the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron. The tiny gap at this junction is called the synaptic gap or synaptic cleft.
synapse
a neurotransmitter’s reabsorption by the sending neuron
reuptake
“morphine within” – natural, opiate-like neurotransmitters linked to pain control and to pleasure
endorphins
chemical messengers that cross the synaptic gaps between neurons.
neurotransmitters
a molecule that increases a neurotransmitter’s action
agonist
a molecule that inhibits or blocks a neurotransmitter’s action
antagonist
the body’s speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous system
nervous system
the brain and spinal cord
central nervous system (CNS)
bundled axons that form neural cables connecting the central nervous system with muscles, glands, and sense organs.
nerves
neurons that carry incoming information from the sensory receptors to the brain and spinal cord
sensory (afferent) neurons
neurons that carry outgoing information from the brain and spinal cord to the muscles and glands
motor (efferent) neurons
neurons within the brain and spinal cord; communicate internally and process information between the sensory inputs and motor outputs
interneurons
the division of the peripheral nervous system that controls the body’s skeletal muscles. Also called the skeletal nervous system
somatic nervous system
the part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart) Its sympathetic division arouses; it’s parasympathetic division calms.
autonomic nervous system (ANS)
the division of the autonomic nervous system that arouses the body, mobilizing it’s energy
sympathetic nervous system
the division of the autonomic nervous system that calms the body, conserving its energy
parasympathetic nervous system
a simple, automatic response to a sensory stimulus, such as the knee-jerk response
reflex
the body’s “slow” chemical communication system; a set of glands that secrete hormones into the bloodstream
endocrine system
chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues
hormones
a pair of endocrine glands that sit just above the kidneys and secrete hormones that help arouse the body in times of stress
adrenal glands
the endocrine system’s most influential gland. Under the influence of the hypothalamus, this gland regulates growth and controls other endocrine glands
pituitary gland
tissue destruction
lesion
an amplified recording of the waves of electrical activity sweeping across the brain’s surface. These waves are measured by electrodes placed on the scalp
electroencephalogram (EEG)
a visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a give task
PET scan
a technique that uses magnetic fields and radio waves to produce computer-generated images of soft tissue.
MRI
a technique for revealing bloodflow and, therefore, brain activity by comparing succesive MRI scans.
fMRI
the oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull; this is responsible for automatic survival functions
brainstem
the base of the brainstem; controls heartbeat and breathing
medulla
the brain’s sensory control center, located on top of the brainstem; it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla
thalamus
a nerve network that travels through the brainstem into the thalamus and plays an important role in controlling arousal
reticular formation
the “little brain” at the rear of the brainstem; functions include processing sensory input, coordinating movement output and balance, and enabling noverbal learning and memory
cerebellum
neural system located below the cerebral hemispheres; associated with emotions and drives
limbic system
two lima-bean-sized neural clusters in the limbic system; linked to emotion
amygdala
a neural structure lying below the thalamus; it direct several maintenance activities (eating, drinking, body temperature) helps govern the endocrine system via the pituitary gland, and is linked to emotion and reward.
hypothalamus
a neural center located in the limbic system; helps process explicit memories for storage
hippocampus
the intricate fabric of interconnected neural cells covering the cerebral hemispheres; the body’s ultimate control and information-processing center
cerebral cortex
portion of the cerebral cortex lying at the top of the head and toward the rear; receives sensory input for touch and body position
parietal
portion of the cerebral cortex lying just behind the forehead; involved in speaking and muscle movements and in making plans and judgements
frontal lobes
portion of the cerebral cortex lying roughly above the ears; includes the auditory areas, each receiving information primarily form the opposite ear
temporal lobes
an area at the rear of the frontal lobes that controls voluntary movements
motor cortex
an area at the rear of the frontal lobes that controls voluntary movements
motor cortex
area at the front of parietal lobes that registers and processes body touch and movement sensations
somatosensory cortex
areas of the cerebral cortex that are not involved in primary motor or sensory functions; rather, they are involved in higher mental functions such as learning, remembering, thinking, and speaking
association areas
the brain’s ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience
plasticity
the formation of new neurons
neurogenesis
the large band of neural fibers connecting the two brain hemispheres and carrying messages between them
corpus callosum
a condition resulting from surgery that isolates the brain’s two hemispheres by cutting the fibers connecting them
split brain
theory which held that bumps on the skull revealed mental abilities + character traits
Phrenology
sends sensory information from tissue and sensory organs INWARD to the brain and spinal cord
Sensory Neurons
work in spinal cord and brain and INTERVENE between sensory and motor neurons
Interneurons
sends instructions OUTWARD from the brain and spinal cord
motor neurons
