Psych Unit 3 Flashcards
a nerve cell; the basic building block of the nervous system
Neurons
the part of the neuron that contains the nucleus; the cell’s life support center
Cell body
a neuron’s often bushy, branching extensions that receive and integrate messages, conducting impulses towards the cell body
Dendrite
the neuron extensions that pass messages through its branches to other neurons or muscles or glands
Axon
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
cells in the nervous system that support, nourish, and protect neurons; they also play a role in learning, thinking, and memory
Glial cells (glia)
a neural impulse; a brief electrical charge that travels down an axon
Action potential
level of stimulation required to trigger a neural impulse
Threshold
in neural processing, 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/ synaptic cleft
Synapse
Chemical messengers that cross the synaptic gaps between neurons. When released by the sending neuron, neurotransmitters travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing whether that neuron will generate a neural impulse
Neurotransmitters
a neurotransmitter’s reabsorption by sending neuron
Reuptake
“the morphine within” - a natural opiate-like neurotransmitter linked to pain control and pleasure
Endorphins
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 systems
Nervous system
the brain and spinal cord
Central nervous system (CNS)
the sensory/ motor neurons that connect the CNS to the rest of the body
Peripheral nervous system (PNS)
bundled axons that form neural cable connecting the central nervous system with muscles, glands, and sense organs
Nerves
neurons that carry incoming info from the body’s tissues/ sensory receptors to the brain/ spinal cord
Sensory (afferent) neurons
neurons that carry outgoing information from the brain and spinal cord to the muscles/ glands
Motor (efferent) neurons
neurons within the brain/spinal cord; they communicate internally/ process information between the sensory inputs/ motor outputs
Interneurons
the division of the peripheral nervous system that controls the body’s skeletal muscles (Skeletal nervous system)
Somatic nervous system
the part of the peripheral nervous system that controls the glands/ muscles of the internal organs. Its sympathetic division arouses; its parasympathetic division calms
Autonomic nervous system (ANS)
the division of the autonomic nervous system that arouses the body, mobilizing its 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 (knee-jerk response)
Reflex
the body’s “slow” chemical communication system; a set of glands that secrete hormones into the bloodstream
Endocrine system
a pair of endocrine glands that sit just above the kidneys/ secrete hormones (epinephrine and norepinephrine) that help arouse the body in times of stress
Adrenal glands
chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream and affect other tissues
Hormones
the endocrine system’s most influential gland. Under the influence of the hypothalamus, the pituitary regulates growth/ controls other endocrine glands
Pituitary gland
is 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
EEG (electroencephalogram)
tissue destruction. A brain lesion is a naturally/ experimentally caused destruction of brain tissue
Lesion
a brain imaging technique that measures magnetic fields from the brain’s natural electrical activity
MEG (magnetoencephalography)
a visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given task
PET (positron emission tomography) scan
a series of X-ray photographs taken from different angles and combined by computer into a composite representation of a slice of the brain structure (CAT scan)
CT (computed tomography) scan
a technique that uses magnetic field/ radio waves to produce computer-generated images of soft tissue, show brain anatomy
MRI (magnetic resonance imaging)
a technique for revealing blood flow and, therefore, brain activity by comparing successive MRI scans, shows how brain function as well as structure
fMRI (functional MRI)
the oldest part/ central core of the brain, beginning where the spinal cord swells as it enters the skull; the brainstem is responsible for automatic survival functions
Brainstem
the base of the brainstem; control heartbeat/breathing
Medulla
the brain’s sensory control center, located at the top of the brainstem; it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum/ medulla
Thalamus
a nerve network that travels through the brainstem into the thalamus, 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/ balance, and enabling nonverbal learning/ memory
Cerebellum
neural system (amygdala, hypothalamus, hippocampus) located below the cerebral hemispheres; associated with emotion/drives
Limbic system
2 lima-bean-sized neural clusters in the limbic system; linked to emotion
Amygdala
a neural structure lying below (hypo) the thalamus; it directs several maintenance activities (eating, drinking, body temperature), helps govern the endocrine system via the pituitary gland, linked to emotion/reward
Hypothalamus
a neural center located in the limbic system helps process for storage of explicit (conscious) memories of facts/ events
Hippocampus
a molecule that increases a neurotransmitter’s action
Agonist
