How can we help?

You can also find more resources in our Help Center.

Chapter 2: The Biology of Mind

STUDY
PLAY
Biological Psychology
A branch of psychology concerned with the links between biology and behavior.
Neuron
A nerve cell; the basic building block of the nervous system.
Sensory Neurons
Neurons that carry incoming information from the sensory receptors to the brain and spinal cord.
Motor Neurons
Neurons that carry outgoing information from the brain and spinal cord to the muscles and glands.
Interneurons
Neurons within the brain and spinal cord that communicate internally and intervene between the sensory inputs and motor ouputs.
Dendrite
The bushy, branching extensions of a neuron that receive messages and conduct impulses toward the cell body.
Axon
The extension of a neuron, ending in branching terminal fibers, through which messages pass to other neurons or to muslces of glands.
Myelin Sheath
A layer of fatty tissue segmentally encasing the fibers of many neurons; enables vastly greater transmission speed of neural impulses as the impulse hops from one node to the next.
Action Potential
A neural impulse; a brief electrical charge that travels down an axon.
Threshold
The level of stimulation required to trigger a neural impulse
Synapse
The junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron.
Neurotransmitters
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.
Reuptake
A neurotransmitter's reabsorption by sending neuron
Endorphins
"Morphine Within"--natural, opiatelike neurotransmitters linked to pain control and to pleasure.
Nervous System
The body's speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems.
Central Nervous System (CNS)
The brain and spinal cord.
Peripheral Nervous System (PNS)
The sensory and motor neurons that connect the central nervous system to the rest of the body.
Nerves
Bundled axons that form neural "cables" connecting the central nervous system with muscles, glands and sense organs
Somatic Nervous System
The division of the peripheral nervous system that controls the body's skeletal muscles.
Autonomic Nervous System
The part of the peripheral nervous system that controls the glands and the muscles of the internal organs. Its sympathetic division arouses; its parasympathetic division calms.
Sympathetic Nervous System
The division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations.
Parasympathetic Nervous System
The division of the autonomic nervous system that calms the body, conserving its energy.
Reflex
A simple, automatic response to a sensory stimulus, such as the knee-jerk response.
Endocrine System
The body's "slow" chemical communication system; a set of glands that secrete hormones into the bloodstream.
Hormones
Chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues.
Adrenal Glands
A pair of endocrine glands that sit just above the kidneys and secrete hormones that help arouse the body in times of stress.
Pituitary Gland
The endocrine system's most influential gland. Under the influence of the hypothalamus, the pituitary regualtes growth and controls other endorcine glands.
Lesion
Tissue Destruction
Electroencephalogram (EEG)
An amplified recording of the waves of electrical activity that sweep across the brain's surface. These waves are measured by electrodes placed on the scalp.
PET (Positron Emission Tomography) Scan
A visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given tasks.
MRI (Magnetic Resonance Imaging)
A technique that uses magnetic fields and radio waves to produce computer-generated images of soft tissue. MRI scans show brain anatomy.
fMRI (Functional MRI)
A technique for revealing bloodflow and, therefore, brain activity by comparing successive MRI scans. fMRI scans show brain function.
Brainstem
The oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull; the brainstem is responsible for automatic survival functions.
Medulla
The base of the brainsterm; controls heartbeat and breathing.
Reticular Formation
A nerve network in the brainsterm that plays an important role in controlling in arousal.
Thalamus
The brain's sensory switchboard, 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.
Cerebellum
The "little brain" at the rear of the brainstem; functions include processing sensory input and coordinating movement output and balance.
Limbic System
Neural System located below the cerebral hemispheres; associated with emotions and drives.
Amygdala
Two lima bean-sized neural clusters in the limbic system; linked to emotion.
Hypothalamus
A neural structure lying below the thalamus; it directs several maintenance activities (eating, drinking, body temperature), helps govern the endocrine system via the pituitary gland, and is linked to emotion and reward.
Cerebral Cortex
The intricate fabric of interconnected neural cells covering the cerebral hemispheres; the body's ultimate control and information-processing center.
Glial Cells (Glia)
Cells in the nervous system that supports, nourish and protect neurons.
Frontal Lobes
Portion of the cerebral cortex lying just behind the forehead; involved in speaking and muscle movements and in making plans and judgements.
Parietal Lobes
Portion of the cerebral cortex lying at the top of the head and toward the rear; receives sensory input for touch and body position.
Occipital Lobes
Portion of the cerebral cortex lying at the back of the head; includes areas that receive information from the visual fields.
Temporal Lobes
Portion of the cerebal cortex lying roughly above the ears; includes the auditory areas, each receiving information primarily from the opposite ear.
Motor Cortex
An area at the rear of the frontal lobes that controls voluntary movements.
Sensory Cortex
Area at the front of the parietal lobes that registers and processes body touch and movement sensations.
Association Areas
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.
Plasticity
The brain's ability to change, especially during the childhood, by reorganizing after damage of by building new pathways based on experience.
Neurogenesis
The formation of new neurons
Corpus Callosum
The large band of neural fibers connecting the two brain hemispheres and carrying messages between them.
Split Brain
A condition resulting from surgery that isolates the brain's two hemispheres by cutting the fibers connecting them.