2 Biological Bases

a branch of psychology concerned with the links between biology and behavior.

a nerve cell; the basic building block of the nervous system.

the bushy, branching extensions of a neuron that receive messages and conduct impulses toward the cell body.

the extension of a neuron, ending in branching terminal fibers through which messages pass to other neurons or to muscles or glands.

a layer of fatty tissue segmentally encasing the fivers of many neurons; enables vastly greater transmission speed of neural impulses as the pulse hops from one node to the next.

a neural impulse; a brief electrical charge that travels down an axon.

a period of inactivity after a neuron has fired

the level of stimulation required to trigger a neural impulse.

a neuron’s reaction of either firing (with a full-strength response) or not firing at all.

the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron. The tiny gap at the junction is called the synaptic gap or synaptic cleft.

chemical messengers that cross the synaptic gaps between neurons. When released by the sending neuron, they travel across the synapse and bind to the receptor sites on the receiving neuron, thereby influencing whether that neuron will generate a neural impulse.

a neurotransmitter's reabsorption by the sending neuron.

"morphine within" - natural, opiate-like neurotransmitters linked to pain control and to pleasure.

a molecule that, by binding to a receptor site, stimulates a response.

a molecule that, by binding to a receptor site, inhibits or blocks a response.

the body's speedy electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems.

the brain and spinal cord.

the sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body.

bundled axons that form neural cables connecting the central nervous system with muscles, glands, and sense of organs.

neurons that carry incoming information from the sensory receptors to the brain and spinal cord.

neurons that carry outgoing information from the brain and spinal cord to the muscles and glands.

neurons within the brain and spinal cord that communicate internally and intervene between sensory inputs and motor outputs.

the division of the peripheral nervous system that controls the body’s skeletal muscles. Also called the skeletal 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; its parasympathetic division calms.

the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations.

the division of the autonomic nervous system that calms the body, conserving its energy.

a simple automatic response to a sensory stimulus, such as the knee-jerk response.

the body's "slow" chemical communication system; a set of glands that secrete hormones into the bloodstreamblood stream.

pair of endocrine glands that sit just above the kidneys and secrete hormones (epinephrine and norepinephrine) that help arouse the body in times of stress.

tissue destruction; a brain lesion is a naturally or experimentally caused destruction of brain tissue.

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.

a series of X-ray photographs taken from different angles and combined by computer into a composite representation of a slice through the body. Also called CAT scan.

a visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given task.

a technique that uses magnetic fields and radio waves to produce computer-generated images of soft tissue. Shows brain anatomy.

a technique for revealing blood flow and, therefore, brain activity by comparing successive MRI scans. Shows brain function.

the oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull; is responsible for automatic survival functions.

doughnut-shaped neural system (including the hippocampus, amygdala, and hypothalamus) located below the cerebral hemispheres; associated with emotions and drives.

cells in the nervous system that support, nourish, and protect neurons.

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.

the brain's ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience.

the formation of new neurons

• a condition resulting from surgery that isolates the brain's two hemispheres by cutting the fibers (mainly those of the corpus callosum connecting them)

• Most often after repeated seizures (epilepsy)

our awareness of ourselves and our environment.

the interdisciplinary study of the brain activity linked with cognition (including perception, thinking, memory, and language).

the principle that information is often simultaneously processed on separate conscious and unconscious tracks.

the study of the relative power and limits of genetic and environmental influences on behavior.

every non-genetic influence, from prenatal nutrition to the people and things around us.

threadlike structures made of DNA molecules that contain the genes.

a complex molecule containing the genetic information that makes up the chromosomes

the biochemical units of heredity that make up the chromosomes; segments of DNA capable of synthesizing a protein.

the complete instructions for making an organism, consisting of all the genetic material in that organism's chromosomes.

twins who develop from a single fertilized egg that splits in two, creating two genetically identical organisms.

twins who develop from separate fertilized eggs. They are genetically no closer that brothers and sisters, but they share a fetal environment.

the subfield of biology that studies the molecular structure and functions of genes.

the proportion of variation among individuals that we can attribute to genes. This may vary, depending on the range of populations and environments studied.

the interplay that occurs when the effect of one factor (such as environment) depends on another factor (such as heredity).

The study of environmental influences on gene expression that occurs without a DNA change

the study of the evolution of behavior and the mind, using principles of natural selection.

the principle that, among the range of inherited trait variations, those that lead to increased reproduction and survival will most likely be passed on to succeeding generations.

a random error in gene replication that leads to a change.

the part of a neuron that contains the nucleus; the cell’s life-support centre

a brain imaging technique that measures magnetic fields from the brain’s natural electrical activity

a condition in which a person can respond to a visual stimulus without consciously experiencing it

processing many aspects of a problem simultaneously; generally used to process well-learned information or to solve easy problems

processing one aspect of a problem at a time; generally used to process new information or to solve difficult problems

the genetic transfer of characteristics from parent to offspring

a culturally modelled guide for how to act in various situations

impairment of language, usually caused by left hemisphere damage either to Broca’s area (impaired speaking) or to Wernicke’s area (impaired meaning of sentences)

an area at the rear of the frontal lobes that controls voluntary movements

• area at the front of the parietal lobes that registers and processes body touch and movement sensations

• receives information from skin surface and sense organs

• portion of the cerebral cortex lying at the top of the head and toward the rear

• receives sensory input for touch and body position

  • proprioception

involved in processing of visual input

• portion of the cerebral cortex lying at the back of the head

• includes areas that receive information from the visual fields.

a brain area involved in language comprehension and expression; usually in the left temporal lobe

• portion of the cerebral cortex lying roughly above the ears

• includes the auditory areas, each receiving information primarily from the opposite ear.

a brain area involved in speaking

• aids emotion regulation

• located in the forward part of the frontal lobes

• enables judgement, planning, and processing of new memories

• damage can impact ability to plan and control emotions

  • case study: Phineas Gage

speaking, making plans and judgments, voluntary muscle movements

• largest part of brain

• handles a wide ranges of responsibilities

• Includes

  • Frontal lobe

  • Occipital lobe

  • Temporal lobe

  • Parietal lobe

• the body's ultimate control and information processing centre for higher-level thinking

• the intricate fabric of interconnected neural cells covering the cerebral hemispheres

• part of the brain stem

• brain’s sensory switchboard

• directs messages to the sensory areas in the cortex and transmits replies to the cerebellum and medulla

the large band of neural fibers connecting the two brain hemispheres and carrying messages between them

• part of the limbic system

• processes conscious, explicit memories

• as we age, size decreases and function declines

• can appear smaller after repeated concussions

• two almond-shaped neural clusters

• part of the limbic system

• linked to emotions of fear and anger

• criminal behaviour can be linked to abnormalities of this structure

• part of the limbic system

• hypo = lies below the thalamus

• directs several maintenance activities like eating, body temperature and control of emotions

• helps govern the endocrine system via the pituitary gland

• linked to reward centre

  • Rat experiment

• the endocrine system’s most influential gland

• under the influence of the hypothalamus, the pituitary regulates growth and controls other endocrine glands

• part of the brainstem

• helps coordinate movement

• Nerve network in the brainstem that plays an important role in controlling arousal as it filters important information

• Severed = coma

• Controls heartbeat and breathing

• Part of the brainstem

  • Located at the base of brainstem

• "little brain" attached to the rear of the brain stem

• processes sensory input and coordinates movement output and balance

• non-verbal memory

• negatively affected by alcohol

the division of the brain into two hemispheres that differ in function

• tendency to remember the first and last elements of a series

  • primacy and recency

chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues

our awareness of ourselves and our environment

a social interaction in which one person (the hypnotist) suggests to another (the subject) that certain perceptions, feelings, thoughts, or behaviours will spontaneously occur

a suggestion, made during a hypnosis session, to be carried out after the subject is no longer hypnotized; used by some clinicians to help control undesired symptoms and behaviours

a split in consciousness, which allows some thoughts and behaviours to occur simultaneously with others

the biological clock; regular bodily rhythms (for example, of temperature and wakefulness) that occur on a 24-hour cycle

rapid eye movement sleep; a recurring sleep stage during which vivid dreams commonly occur. Also known as paradoxical sleep, because the muscles are relaxed (except for minor twitches) but other body systems are active

the relatively slow brain waves of a relaxed, awake state