Psyc 412 1st EditionExam # 2 Study Guide Lectures: 9-13Chapter 2- Nervous system: a complex network of interconnected nerve fiberso Sensory nerve fibers provide input to the brain and spinal cord by carrying signalsfrom sensory receptorso Motor nerve fibers provide output from the brain or spinal cord to muscles and other organs (voluntary/involuntary movement)- Nervous systemo Central nervous system Brain Spinal cordo Peripheral nervous system- Somatic nervous system (Voluntary movement)- Autonomic nervous system (Involuntary movement), SNS and PNS act in complement to each othero Sympathetic nervous system: prepares the body to respond to emergencies, strong emotions, and strenuous activity Important role with reactions to stress Catabolic system Increases during an emergency or times of high activity (exercise), start to sweat, pupils dilateo Parasympathetic nervous system: controls the activities of organs under normal circumstances and acts antagonistically to SNS; helps restore body to normal state after emergency passes Anabolic system The rest of the time (digestion, rest)- Brain: the command center of the bodyo Receives afferent (sensory) impulses and sends efferent (motor) impulses- Hindbrain: made up of medulla, pons, and cerebellumo Medulla: Located just above point where spinal cord enters the skull Basic biological function, primitive Responsible for regulation of heart rate, blood pressure, respirationo Pons Link between the hindbrain and midbrain  Helps control respiration In charge of sleep/wakefulnesso Cerebellum “little brain” Coordinates voluntary muscle movement Maintenance of balance and coordination Maintenance of muscle tone and posture Combination of motor and gross coordination- Midbrain: major pathway for sensor and motor impulses moving between forebrain and hindbraino Responsible for coordination of visual and auditory reflexeso Superior and inferior colliculi: responsible for peripheral reflexes (superior colliculi) and auditory reflexes (inferior colliculi)- Forebrain: two main section:o Diencephalon Thalamus: involved in recognition of sensory stimuli and relay of sensory impulses to cerebral cortex- Relay center for brain Hypothalamus: helps regulate cardiac functioning, blood pressure, and respiration- Regulates water balance in the body- Regulates appetites (hunger and sexual desire)- Important transition center between thoughts and impact on organs- Important for stress response; regulates fight-or-flight response- Regulates body temperatureo Telencephalon Composed of left and right hemispheres of cerebral cortex Cerebral cortex: largest portion of the brain; involved in higher-order intelligence, memory, personality; has 4 lobes- Frontal lobeo Contains motor cortex: coordinates voluntary movement Left part of motor cortex controls right side of body Right part of motor cortex controls left side of body- Parietal lobeo Contains somatosensory cortex: sensations of touch, pain, temperature, pressure are registered and interpretedo Tactile and spatial information, somatosensory strip- Temporal lobeo Contains cortical areas responsible for auditory and olfactory impulses- Occipital lobe o Contains visual cortex, receives visual impulses- Wernicke’s area: spans the parietal and temporal lobeso Involved in understanding speecho Can hear words but can’t understand them, speak garbled words (“nonsense”)- Basal ganglia: embedded in cerebrum; help make muscle contractions orderly, smooth, and purposeful- Limbic system: play important role in stress and emotional responseso Amygdala: detection of threato Hippocampus: memories  Transfer memory from short-term to long-term Works with amygdala to make memories coupled with fear very potent, could cause phobias (emotionally charged)o Anterior part of thalamus: important for socially relevant behaviors- Neurotransmitters: chemicals that regulate nervous system functioningo Catecholamines: epinephrine and norepinephrine Secreted when sympathetic nervous system stimulated Secretion results in: heart rate increases, blood vessels constrict, blood pressure increases, respiration rate goes up, digestion/urination decreased, pupils dilate, sweat glands produce more sweat- About 20 million Americans have a disorder of the nervous systemo Epilepsy: disease of central nervous system affecting over 3 million people in U.S. Often idiopathic (no specific cause for symptoms can be identified) Marked by seizures accompanied by irregular breathing, drooling, and lossof consciousness Can’t be cured, can be controlled with medication and behavioral interventions to manage stresso Cerebral palsy: progressive degeneration of the basal ganglia Tremors, rigidity, slowness of movement Over 1 million Americans affected, mostly affects those over 50 years old Cause not known, may be influenced by depletion of neurotransmitter dopamine Can be treated with doses of dopamine, but has undesirable side effectso Multiple sclerosis: degenerative disease of certain brain tissues can cause paralysis and sometimes blindness, deafness, mental deterioration Affects 400,000 Americans, 200 people diagnosed every week Early symptoms: numbness, double vision, dragging of feet, loss of bowel control, speech difficulties, extreme fatigue (causes different symptoms depending on where it affects) Results from disintegration of myelin Autoimmune disorder: immune system fails to recognize its own tissue and attacks the myelin sheath around nerves May be link to a lack of vitamin Do Huntington’s Disease: hereditary disorder of central nervous system characterizedby chronic physical and mental deterioration Symptoms: involuntary muscle spasms, loss of motor abilities, personalitychanges, mental disintegration Affects 300,000 Americans  Gene has been isolated and tests exist to determine when disease will start to affect a persono Polio: poliomyelitis is a viral disease that attacks the spinal nerves and destroys cell bodies of motor neurons so motor impulses can’t be carried from spinal cord outward to peripheral nerves or muscles Can cause difficulties walking and moving properly, may have shrunken and ineffective limbs to full paralysis A vaccine exists- Paraplegia: paralysis of lower extremities of bodyo Results from injury to lower portion of spinal cord- Quadriplegia: paralysis of all 4 extremities