Unit 3: Biological Bases of Behavior Flashcards
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 outputs.
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 muscles or 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. The tiny gap at this junction is called the synaptic gap (or synaptic cleft)
Neurotransmitters
chemical messengers that cross the synaptic gaps between neurons. When released by the sending neuron, they travel across the synapse and bind to receptor sites on the receiving neuron, influencing whether that neuron will generate a neural pulse.
Endorphins
“morphine within” - natural opiate like neurotransmitters linked to pain control and to pleasure
Agonist
a molecule similar enough to a neurotransmitter to bind to its receptor and mimic its effects (drugs)
Antagonists
also bind the receptors, but block a neurotransmitters functioning
Reuptake
a neurotransmitter’s reabsorption by sending neuron
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
the sensory and motor neurons that connect the central nervous system with 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 (Also called the skeletal nervous system)
Autonomic nervous system
the part of the PNS that controls the glands and the muscles of the internal organs
Sympathetic nervous system
the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations
Parasympathetic nervous sytem
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
Spinal Cord
the informational highway that connects the brain to the PNS
Endocrine system
the body’s “slow” chemical communication system; a set of glands that secrete hormones into the blood stream
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 about the kidneys and secrete hormones (epinephrine and norepinephrine) 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 regulates growth and controls other endocrine glands
Electroencephalogram (ECG)
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.
Computed tomography (CT scan)
a series of x-ray photographs taken from different angles and combined by computer into a composite representation of a slice through the body (CAT scan)
Position emission tomography (PET scan)
a visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given task
Magnetic resonance Imaging (MRI)
a technique that uses magnetic fields and radio waves to produce computer generated images of soft tissue (show brain anatomy)
fMRI
a technique for revealing blood flow and, therefore, brain activity by comparing successive MRI scans
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
Reticular formation
a nerve network in the brainstem that controls arousal
Medulla
the base of the brainstem; controls heartbeat and breathing
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 its 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
doughnut-shaped 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 temp.), 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
cells in the nervous syatem that support, nourish and protect neurons
Frontal lobe
portion of the cerebral cortex lying just behind the forehead; involved in speaking and muscles 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 cerebral 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 (output)
Sensory cortex
area at the front of the parietal lobes that registers and processes body touch and movement sensations (input)
Association 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
Phasia
impairment of language usually caused by left hemisphere damage to Broca’s area (impairing speaking) or to Wernicke’s area (impairing understanding)
Broca’s area
controls language expression - an area, usually in the left frontal lobe, that directs the muscles movements involved in speech
Wernicke’s area
controls language reception - a brain area involved in language comprehension and expression; usually in the left temporal lobe
Plasticity
the brain’s ability to change, especially during childhood, by reorganizing after damage or 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
Right hemisphere
makes inferences
makes meaning clear
orchestrates our sense of self
visual perception
recognition of emotion
Left hemisphere
makes quick literal interpretations of language
more verbal
Consciousness
our awareness of ourselves and our environment
Cognitive neuroscience
the interdisciplinary study of the brain activity linking with cognition (including perception, thinking, memory and language)
Dual processing
the principle that information is often simultaneously processed on seperate conscious and unconscious tracks
Behavior geneticists
the study of relative power and limits of genetic and environmental influences on behavior
Environment
every nongenetic influence, from prenatal nutrition to the people and things around us
Chromosomes
thread like structures made of DNA molecules that contain the genes
DNA (deoxyribonucleic acid)
a complex molecule containing genetic information that makes up the chromosomes
Genes
the biochemical units of heredity that make up the chromosomes; segments of DNA capable of synthesizing a protein
Genome
the complete instructions for making an organism , consisting of all the genetic material in that organism’s chromosomes
Identical twins
twins who develop from a single fertilized egg that splits in two, creating two genetically identical organisms
Fraternal twins
twins who develop from separate fertilized eggs. They are genetically no closer than brothers and sisters, but they share a fetal environment
Heritability
the proportion of variation among individuals that we can attribute to genes
Nature vs nurture
Hereditary deals the cards, environment plays the hand
Molecular genetics
the subfield of biology that studies the molecular structure and function of genes
Evolutionary psychology
the study of the evolution of behavior and the mind, using the principles of natural selection
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
Mutation
a random error in gene replication that leads to a change
