Unit 2
Nervous System- The body’s electrochemical communication circuitry
Plasticity- The brain's special capacity for change
Neuron- Nerve cell that allows electrical impulses to travel
Afferent Nerves- Sensory nerves that carry information to the brain and spinal cord
Efferent Nerves- Motor nerves that carry information out of the brain and spinal cord to communicate with muscles for example what to do
Neural Networks- Interconnected groups of nerve cells that integrate sensory input and motor output (make up most of the brain)
Central Nervous System- The brain and spinal cord
Peripheral Nervous System- The network of nerves that connects the brain and spinal cord to other parts of the body
Somatic Nervous System- Sensory nerves (afferent) which convey information from the skin and muscles to the central nervous system about conditions such as pain and motor nerves (efferent) which tell muscles what to do
Autonomic Nervous System- The body system that takes messages to and from the body’s internal organs, monitoring such processes as breathing and heart rate
Sympathetic Nervous System- Part of the autonomic nervous system that arouses the body to mobilize it for action and this is involved in the experience of stress
Parasympathetic Nervous System- Part of the autonomic nervous system that calms the body
Stress- The responses of individuals to environmental stressors
Stressors- Circumstances and events that threaten individuals and tax their coping abilities and that cause physiological changes to ready the body to hand the assault of stress
Corticosteroids- When we experience stress we release this which are powerful stress hormones
Acute Stress- The momentary stress that occurs in response to life experiences
Chronic Stress- Stress that goes on continuously and may lead to persistent autonomic nervous system arousal
2.2
Neurons- The nerve cells that hand the information-processing function
Mirror Neurons- Play a role in imitation and are activated when we perform an action but also when we watch someone else perform the same task
Glial Cells- Provide support, nutritional benefits, and other functions in the nervous system (pit crew for Neurons)
Cell body- The part of the neuron that contains the nucleus, which directs the manufacture of substances that the neuron needs for growth and maintenance
Dendrites- Treelike fibers projecting from a neuron that receive information and orient it towards the neurons cell body
Axon- Part of the neuron that carries information away from the cell body towards other cells
Myelin Sheath- A layer of fat cells that encases and insulates most axons
Semipermeable- fluids can sometimes flow in and out of the gates of a membrane
Ions- electrically charged particles that float in and out of the axons membranes to create electrical signals
Ion Channels- Open and close to let ions pass into and out of the cell
Resting- When a neuron is not transmitting information
Polarized- The difference in ion charge by the membranes of axons
Resting Potential- A stable negative charge of an inactive neuron
Action Potential- The brief wave of positive electrical charge that sweeps down the axon
All-or-nothing principle- Once the electrical impulse reaches a certain level of intensity, called its threshold, it fires and moves all the way down the axon
Synapses- Tiny spaces between neurons; the gap between neurons is referred to as a synaptic gap
Terminal Buttons- Axons branch out into these structures
Neurotransmitters- Transmit, or carry, information across the synaptic gap to the next neuron
Reuptake- Neurotransmitters can sometimes be reabsorbed by the axon to await the next neural impulse
Acetylcholine- A chemical that usually stimulates the firing of neurons and is involved in the action of muscles
GABA- found throughout the central nervous system and is believed to be the neurotransmitter in as many as one-third of the brain's synapses
Glutamate- Key role in exciting many neurons to fire and is especially involved in learning and memory
Norepinephrine- Inhibits the firing of neurons in the CNS but excites the heart muscle, intestines, and urogenital tract
Dopamine- Helps to control voluntary movement and affects sleep, mood, attention, and learning
Serotonin- Regulation of sleep, mood, attention, and learning
Endorphins- Natural opiates that mainly stimulates the firing of neurons
Oxytocin- A hormone and neurotransmitter that plays an important role in the experience of love and social bonding
Agonist- A drug that mimics or increases a neurotransmitters effects
Antagonist- A drug that blocks a neurotransmitter’s effects
4.3
Brain Lesioning- An abnormal disruption in the tissue of the brain resulting from injury or disease
Electroencephalograph (EEG)- Records the brain's electrical activity
Positron-emission Tomography (PET) - A scan based on metabolic changes in the brain related to activity. PET measures the amount of glucose in various areas of the brain
Magnetic Resonance Imaging (MRI) - Creating a magnetic field around a person's body and using radio waves to construct images of the persons tissues and activities
Hindbrain- The lowest portion of the brain which contains the medulla, cerebellum, and pons
Medulla- begins where the spinal cord enters the skull and controls vital functions such as breathing and heart rate
Cerebellum- Extends from the rear of the hindbrain, just above the medulla, and plays important roles in motor coordination
Pons- a bridge between the hindbrain and the brain stem and contains several clusters of fibers involved in sleep and arousal
Brain Stem - Includes much of the hindbrain and midbrain and gets the name because it looks like a stem
Midbrain - An area in which many nerve-fiber systems ascend and descend to connect the higher and lower portions of the brain
Reticular Formation - A system in the midbrain comprising a diffuse collection of neurons involved in stereotyped patterns of behavior such as walking, sleeping, and turning to attend to a sudden noise
Forebrain- The largest division and the most important part
Limbic System - A network of structures under the cerebral cortex; A set of subcortical brain structures central to emotion, memory, and reward processing
Amygdala - An almond shaped structure located inside the brain towards the base involved in discrimination of objects that are necessary for the organisms survival such as appropriate mates, food ect (limbic)
Hippocampus - Has a special role in the storage of memories (limbic)
Thalamus - A structure that sits on top of the brain stem; serves as an essential relay station, functioning much like a server in a computer network
Basal Ganglia - A cluster of neurons that sit below the cerebral cortex and atop the thalamus which works with the cerebellum and cerebral cortex to control and coordinate voluntary movements
Hypothalamus - A small structure just below the thalamus which monitors three pleasurable activities: eating, drinking, and sexual behavior; regulates the bodys internal state
Cerebral Cortex - Outer layer of the brain responsible for the most complex mental functions such as thinking and planning
Neocortex - The outermost part of the cerebral cortex making up 80% of the brains cortex
Occipital Lobes - Located at the back of the brain, respond to visual stimuli
Temporal Lobes - The part of the cerebral cortex just above the ears, involved in hearing, language processing, and memory
Frontal Lobes - The portion of the cerebral cortex behind the forehead are involved in personality, intelligence, and the control of voluntary muscles
Prefrontal Cortex - A part of the frontal lobe that is involved in higher cognitive functions such as planning, reasoning, and self-control
Parietal Lobes - Located at the top of the head are involved in registering spatial location, attention, and motor control
Somatosensory Cortex - A region in the cerebral cortex that processes information bout body sensations
Motor Cortex - A region in the cerebral cortex located just behind the frontal lobe that processes information about voluntary movements
Association Cortex - Sometimes called association areas is the region that holds the highest intellectual functions such as thinking and problem solving
Broca’s Area - plays an important role in the production of speech
Wernicke’s area - Comprehending language
Corpus Callosum - The bundle of axons connecting the brains two hemispheres and is responsible for relaying information
Left Hemisphere - Speech and grammar are localized to the left hemisphere; most language comes from this side
Right hemisphere - Dominates nonverbal information such as spatial perception, visual recognition, and emotion
2.4
Endocrine System - Consists of a set of glands that regulate the activities of certain organs by releasing their chemical products into the bloodstream
Glands - Organs or tissues in the body that create chemicals that control bodily functions
Hormones- The chemical messages that are produced by endocrine glands
Pituitary Gland - A pea sized gland that controls growth and regulates other glands
Adrenal Glands - Located at the top of each kidney which regulates mood, energy level, and ability to cope with stress
Pancreas - Located under the stomach performs both digestive and endocrine functions
Ovaries/Testes - Sex related endocrine glands that produce hormone related to sexual development and reproduction
2.5
Collateral Sprouting - Axons of some healthy neurons adjacent to damaged cells grow new branches
Substitution of function - Damaged region’s function is taken over by another area
Neurogenesis - The process by which new neurons are generated
Brain Grafts - Implants of healthy tissue into damaged brains
Stem Cells - Primitive cells that have the capacity to develop into most types of human cells
2.6
Chromosomes - Threadlike structures that come in 23 pairs that contain DNA
DNA - A complex molecule in the cells chromosomes that carries genetic information
Genes - The units of hereditary information consisting of short segments of chromosomes composed of DNA
Dominant-recessive Gene Principles - If one gene of a pair is dominant and another is recessive, the dominant one overrides the recessive gene
Linkage Analysis - Link between what genes cause blue eyes for example
Genotype - A person's genetic heritage
Phenotype - Observable characteristics
Gene x environment interaction - The interaction of a specific measurable variation in DNA and a specific measured aspect of the environment
Risk Factor - Characteristics, experiences, or exposures that increase the likelihood that a person will develop a psychological disorder