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16 Neural Integration II: The Autonomic Nervous System and Higher-Order Functions PowerPoint® Lecture Presentations prepared by Jason LaPres Lone Star College—North Harris © 2012 Pearson Education, Inc. An Introduction to the ANS and Higher-Order Functions Learning Outcomes 16-1 Compare the organization of the autonomic nervous system with that of the somatic nervous system. 16-2 Describe the structures and functions of the sympathetic division of the autonomic nervous system. 16-3 Describe the mechanisms of sympathetic neurotransmitter release and their effects on target organs and tissues. 16-4 Describe the structures and functions of the parasympathetic division of the autonomic nervous system. 16-5 Describe the mechanisms of parasympathetic neurotransmitter release and their effects on target organs and tissues. 16-6 Discuss the functional significance of dual innervation and autonomic tone. 16-7 Describe the hierarchy of interacting levels of control in the autonomic nervous system, including the significance of visceral reflexes. 16-8 Explain how memories are created, stored, and recalled, and distinguish among the levels of consciousness and unconsciousness. 16-9 Describe some of the ways in which the interactions of neurotransmitters influence brain function. 16-10 Summarize the effects of aging on the nervous system and give examples of interactions between the nervous system and other organ systems. © 2012 Pearson Education, Inc. An Introduction to the ANS and Higher-Order Functions Somatic Nervous System (SNS)—operates under conscious control SNS controls skeletal muscles Autonomic Nervous System (ANS)—operates without conscious instruction ANS controls visceral effectors and coordinates system functions (Cardiovascular, respiratory, digestive, urinary, reproductive) © 2012 Pearson Education, Inc. 16-1 Divisions of the ANS The Autonomic Nervous System Operates largely outside our awareness Has two divisions Sympathetic division Increases alertness, metabolic rate, and muscularabilities “Kicks in” only during exertion, stress, or emergency “Fight or flight” Parasympathetic division Reduces metabolic rate and promotes digestion Controls during resting conditions “Rest and digest” © 2012 Pearson Education, Inc. 16-1 Divisions of the ANS Sympathetic and Parasympathetic Division Most often, these two divisions have opposing effects If the sympathetic division causes excitation, the parasympathetic causes inhibition The two divisions may also work independently Only one division innervates some structures The two divisions may work together, with each controlling one stage of a complex process 1 Because the sympathetic division of the ANS stimulates tissue metabolism and increases alertness, it is called the _____ subdivision. 2 Because the parasympathetic division of the ANS conserves energy and promotes sedentary activity, it is known as the ____ subdivision. 3 A third division of the ANS is the _____________. © 2012 Pearson Education, Inc. 16-1 Divisions of the ANS Seven Responses to Increased Sympathetic Activity Heightened mental alertness Increased metabolic rate Reduced digestive and urinary functions Energy reserves activated Increased respiratory rate and respiratory passageways dilate Increased heart rate and blood pressure Sweat glands activated Five Responses to Increased Parasympathetic Activity Decreased metabolic rate Decreased heart rate and blood pressure Increased secretion by salivary and digestive glands Increased motility and blood flow in digestive tract Urination and defecation stimulation © 2012 Pearson Education, Inc. 16-2 The Sympathetic Division Changes Caused by Sympathetic Activation Increased alertness Feelings of energy and euphoria Change in breathing Elevation in muscle tone Mobilization of energy reserves © 2012 Pearson Education, Inc. 16-4 The Parasympathetic Division Major Effects of Parasympathetic Division Constriction of the pupils Secretion by digestive glands Secretion of hormones Changes in blood flow and glandular activity Increase in smooth muscle activity Stimulation and coordination of defecation Contraction of the urinary bladder during urination Constriction of the respiratory passageways Reduction in heart rate and in the force of contraction © 2012 Pearson Education, Inc. Table 16-2 A Structural Comparison of the Sympathetic and Parasympathetic Divisions of the ANS 4 The sympathetic effects on the eye is to _____, while the parasympathetic effect on the eye is to ____________. 5 The sympathetic effects on the heart is to _______________, while the parasympathetic effect on the heart is to _________________. © 2012 Pearson Education, Inc. 16-8 Higher-Order Functions Higher-Order Functions Share Three Characteristics Require the cerebral cortex Involve conscious and unconscious information processing Are not part of programmed “wiring” of brain © 2012 Pearson Education, Inc. 16-8 Higher-Order Functions Memory Fact memories (are specific bits of information) Skill memories (are learned motor behaviors that are incorporated at unconscious level with repetition) Short-term memories Information that can be recalled immediately Contain small bits of information Primary memories Long-term memories Memory consolidation – conversion from short-term to long-term memory Two types of long-term memory Secondary memories fade and require effort to recall Tertiary memories are with you for life 6 The loss of memory as a result of disease or trauma is ________. © 2012 Pearson Education, Inc. 7 The conversion from short-term to long-term memory is called _____. © 2012 Pearson Education, Inc. 16-8 Higher-Order Functions States of Consciousness Degree of wakefulness indicates level of ongoing CNS activity When abnormal or depressed, state of wakefulness is affected Deep sleep Also called slow-wave or Non-REM (NREM) sleep. The entire body relaxes and the cerebral cortex activity is minimal. Rapid eye movement (REM) sleep. When active dreaming occurs. Changes in blood pressure and respiratory rate Less receptive to outside stimuli than in deep sleep Muscle tone decreases markedly Eyes move rapidly as dream events unfold © 2012 Pearson Education, Inc. © 2012 Pearson Education, Inc. 16-8 Higher-Order Functions States of Consciousness Nighttime sleep pattern alternates between levels Begins in deep sleep REM periods average 5 minutes in length; increase to 20 minutes over 8 hours © 2012 Pearson Education, Inc. 16-8 Higher-Order Functions Sleep Has important impact on CNS Produces only minor changes in physiological activities of organs and systems Protein synthesis in neurons increases during sleep Extended periods without sleep lead to disturbances in mental function 25% of the U.S. population experiences sleep disorders 8 The degree of wakefulness at any moment is an indication of the level of ongoing ___ activity. 9 Active dreaming occurs during _____ sleep. © 2012 Pearson Education, Inc. 16-10 Effects of Aging on the Nervous System Effects of Aging Anatomical and physiological changes begin after maturity (age 30) and they acumulate over time 85% of people over age 65 have changes in mental performance and CNS function Common Age-related Anatomical Changes in the Nervous System Reduction in Brain Size and Weight (reduction in cerebral cortex) Reduction in Number of Neurons (reduction in cortical neurons) Decrease in Blood Flow to Brain (fatty acid deposits that reduce blood flow) Changes in Synaptic Organization of Brain (decreased dendritic branches, spines and interconnections) Intracellular and Extracellular Changes in CNS Neurons (accumulate abdormal deposits) 10 An example of an abnormal intracellular deposit is _________. © 2012 Pearson Education, Inc. 16-10 Effects of Aging on the Nervous System Anatomical Changes Linked to functional changes Neural processing becomes less efficient with age Memory consolidation more difficult Secondary memories harder to access Sensory Systems Hearing, balance, vision, smell, and taste become less acute Reaction times slowed Reflexes weaken or disappear Motor Control Precision decreases Takes longer to perform © 2012 Pearson Education, Inc. 16-10 Effects of Aging on the Nervous System Incapacitation 85% of elderly population develops changes that do not interfere with abilities Some individuals become incapacitated by progressive CNS changes Senility (senile dementia) Degenerative changes: Memory loss, anterograde amnesia (lose ability to store new memories), emotional disturbances, Alzheimer’s disease is most common 11 The most common and disabling form of senile dementia is ______. © 2012 Pearson Education, Inc. 16-10 Nervous System Integration The Nervous System Monitors all other systems Issues commands that adjust their activities Like conductor of orchestra 12 Alzheimer’s disease (AD) is _________________________________________. © 2012 Pearson Education, Inc.