Unit 3: Modules 9-11 Flashcards
A nerve cell, the basic building block of the nervous system
Neuron
The part of the neuron that contains the nucleus, the cell’s life-support center
Cell Body (soma)
A neuron’s often bushy, branching extensions, that receive and integrate messages, conducting impulses toward the cell body
Dendrites
The neuron extension that passes messages through its branches to other neurons or to muscles or glands
Axon
A fatty tissue layer that segmentally encases the axons of some neurons, enables vastly greater transmission speed as neurons 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
A neural impulse, a brief electronically charge that travels down an axon
Action Potential
The level of stimulation required to trigger a neural impulse
Threshold
In neural processing, a brief resting pause that occurs after 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 or receiving neuron. The tiny gap at this junction is called:
Synapse or synaptic cleft
Chemical transmitter that crosses the synaptic gap between neurons, when released by sending neurons, they travel across the synapse and bind to receptor sites on the receiving neuron, influencing whether that neuron will generate a neural impulse
Neurotransmitter
Neurotransmitter’s reabsorption by the sending neuron
Reuptake
Natural, opiate-like neurotransmitters linked to pain control and to pleasure, “morphine-within”
Endorphins
Molecule that increases a neurotransmitter’s action
Agonist
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 and motor neurons that connect the central nervous system to the rest of the body
Peripheral Nervous System (PNS)
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 body’s tissues and 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 sensory inputs and motor outputs
Interneurons
Division of the peripheral nervous system that controls the glands and muscles of internal organs (ex: the heart) sympathetic - arouses parasympathetic - calms
Autonomic Nervous System
The division of the autonomic nervous system that arouses the body, mobilizing its energy
Sympathetic Nervous System
Division of the autonomic system that calms the body, conserving its energy
Parasympathetic Nervous System
A simple, automatic response to a sensory stimulus, such as a knee-jerk reaction
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 tissue
Hormones
Pair of endocrine glands that sit just above the kidneys and secrete hormones (epinephrine and norepinephrine) in times of stress
Adrenal Glands
The endocrine system’s most influential gland. Under the influence of the hypothalamus, the pituitary regulates growth and controls the other endocrine glands.
Pituitary Gland
Tissue destruction, is a naturally or experimentally caused destruction of brain tissue
Lesion
Amplified recording of the waves of electrical activity sweeping across the brain’s surface. These waves are measured by electrodes placed on scalp.
Electroencephalography (EEG)
Brain imaging technique that measures magnetic fields from the brain’s natural electrical activity
Magnetoencephalography (MEG)
Series of x-ray photographs taken from different angles and combined by computer into a composite representation of a slice of brain’s structure (CAT Scan)
CT (computed tomography) Scan
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
Technique that uses magnetic fields and radio waves to produce computer generated images of soft tissue. Shows brain anatomy.
MRI (magnetic resonance imaging)
A technique for revealing blood flow, and therefore, brain activity by comparing successive MRI scans. Shows brain function and structure.
fMRI (functional MRI)
Oldest part and central core of the brain, begins where spinal cord swells as it enters the skull, is responsible for automatic survival functions
Brainstem
Base of the brainstem, controls heartbeat and breathing
Medulla
Nerve network that travels through the brainstem into the thalamus and plays an important role in controlling arousal
Retricular Formation
Brain’s sensory control center, directs messages to sensory receiving areas in cortex and transmits replies to cerebellum and medulla
Thalamus
“Little Brain” at the rear of brainstem, processes sensory input, coordinating movement output and balance, enabling nonverbal learning and memory
Cerebellum
Neural system (including amygdala, hypothalamus, hippocampus) located below cerebral hemispheres associated with emotions and drives
Limbic system
Two-lima-bean sized neural clusters in the lambic system, linked to emotion
Amygdala
Neural structure lying below the thalamus, directs maintenance activities (eating, drinking, body temperature) governs endocrine system with pituitary, limited to emotion and reward
Hypothalamus
Neural center located in limbic system, helps process for storage explicit (conscious) memories of facts and events
Hippocampus
