Chapter 1 The Physical Foundation of Behavior

© Copyright 2009 Delmar, Cengage Learning. All Rights Reserved.2 The Influence of DNA DNA: complex set of plans (genes) stored in the nucleus of each cell Fraternal twins: develop from separate fertilized eggs Identical twins: develop from one fertilized egg and have identical DNA

© Copyright 2009 Delmar, Cengage Learning. All Rights Reserved.3 The Nervous System Neurons: the working cells of the nervous system have three basic parts; (See textbook Figure 1-2.) –Cell body: bulk of the cell that contains the nucleus and the cell machinery –Dendrites: fibers that carry electrical impulses to the cell body –Axons: fibers that take electrical impulses away from the cell body

© Copyright 2009 Delmar, Cengage Learning. All Rights Reserved.4 The Nervous System Tracts : long bundles of fibers that carry electrical impulses inside of the central nervous system Nerves: long bundles of fibers that carry electrical impulses in the peripheral nervous system

© Copyright 2009 Delmar, Cengage Learning. All Rights Reserved.5 Myelin sheath: a covering wrapped around some nerve fibers that greatly increases the speed of electrical impulses (See textbook Figure 1-2.) Synapse: a specialized structure that forms a junction between two neurons or between a neuron and another type of cell (See textbook Figure 1-4.) The Nervous System

© Copyright 2009 Delmar, Cengage Learning. All Rights Reserved.6 Neurotransmitters: chemicals that pass an electrical impulse from one neuron to another across a synapse Neuroinhibitors: chemicals that stop electrical impulses from being passed from one neuron to another across a synapse The Nervous System

© Copyright 2009 Delmar, Cengage Learning. All Rights Reserved.7 The Influence of the Environment Neurodevelopment: the growth and organization of the nervous system Decisions: all connected neurons have input into the decision a neuron makes Astrocytes: support cells in the brain and spinal cord Domain: a group of neurons tied together by one astrocyte

© Copyright 2009 Delmar, Cengage Learning. All Rights Reserved.8 Organization of the Nervous System The Nervous System: is divided into three primary divisions; (See textbook Figure 1-6.) –Sensory: neurons outside of the brain or spinal cord extend fibers into the body to pick up information –Association: neurons in the brain receive information from the sensory neurons, process the input and make decisions

© Copyright 2009 Delmar, Cengage Learning. All Rights Reserved.9 Organization of the Nervous System –Motor division: motor neurons receive impulses from association neurons and carry them back to muscles,organs, and glands. Motor nervous system: is then divided into two groups; (See textbook Figure 1-7.) Somatic division Autonomic division

© Copyright 2009 Delmar, Cengage Learning. All Rights Reserved.10 Somatic: motor neurons that carry electrical impulses to voluntary muscles (muscle that can be moved at will) Autonomic: the division with motor neurons that take impulses to glands and to involuntary muscles in the heart, organs, and blood vessels Organization of the Nervous System

© Copyright 2009 Delmar, Cengage Learning. All Rights Reserved.11 Autonomic Nervous System: is subdivided into two divisions: – Sympathetic: motor neurons that move things away from normal and is responsible for “flight or fight” and stress reactions – Parasympathetic: returns everything back to normal Organization of the Nervous System

© Copyright 2009 Delmar, Cengage Learning. All Rights Reserved.12 The Brain Brain: encased in the skull, is the central processing unit for the nervous system and has four major divisions: (See textbook Figure 1-8) –Brain stem –Diencephalon –Cerebellum –Cerebrum

© Copyright 2009 Delmar, Cengage Learning. All Rights Reserved.13 Brain stem: carries out processes vital to the physical well being and survival of the body; connects the rest of the brain to the spinal cord Diencephalon: contains the thalamus and the hypothalamus and is the major switchboard of the brain The Brain

© Copyright 2009 Delmar, Cengage Learning. All Rights Reserved.14 Cerebellum: coordinates the activities of voluntary muscles Cerebrum: largest part of the brain and divided into right and left hemispheres. Contains sensory and motor areas and is the seat of higher mental functions. Has centers that activate and inhibit behavior The Brain

© Copyright 2009 Delmar, Cengage Learning. All Rights Reserved.15 The Functional Brain Functional divisions: the functional layers of the brain include (See textbook Figure 1-10.) –Brain stem –Reptilian complex –Limbic system –Neocortex

© Copyright 2009 Delmar, Cengage Learning. All Rights Reserved.16 The Functional Brain Brain stem: most primitive part of the brain; controls processes vital to physical functioning of the body Reptilian complex: layer of brain over the brain stem. The seat of status and territory; enables more complicated behaviors in life.

© Copyright 2009 Delmar, Cengage Learning. All Rights Reserved.17 The Functional Brain Limbic system: motivates and guides group behavior; situated at the base of the cerebrum; known as the emotional brain Neocortex: most complex development in the brain; composed of the bulk of the cerebrum. Responsible for higher mental functions that we identify with being human and humane.

© Copyright 2009 Delmar, Cengage Learning. All Rights Reserved.18 Consciousness Consciousness: a great mystery. Awareness including self awareness Spirit: The origin of belief in a spirit is unknown. Consciousness has been equated as the Spirit within us. Belief is widespread and the basis of most religion.

© Copyright 2009 Delmar, Cengage Learning. All Rights Reserved.19 Consciousness Chemical consciousness: scientific view. Result of patterns and concentrations of chemicals in the brain Quantum consciousness: emerging view. Based in quantum waves isolated in the neurons of the brain; contains elements of spiritual and chemical consciousness

© Copyright 2009 Delmar, Cengage Learning. All Rights Reserved.20 Consciousness Void: Mathematics is the only language that describes the void. Quantum computers have the potential to be more powerful than a conventional computer. Still rudimentary, they open the possibility that consciousness may be a quantum phenomenon

© Copyright 2009 Delmar, Cengage Learning. All Rights Reserved.21 Metaphysics Metaphysics: reality and rules beyond the limits of the universe and understanding. Recognized and identified by –Science: as an existence and a power which creates and sustains the universe –Religion: as an existence and power Who creates and sustains the universe

© Copyright 2009 Delmar, Cengage Learning. All Rights Reserved.22 Summary DNA is the genetic material received from our parents At birth the brain is about 15% developed Growth of the brain is a long and complex process which requires both genetic plans and interactions with the environment

© Copyright 2009 Delmar, Cengage Learning. All Rights Reserved.23 Summary The brain is divided both structurally and functionally and each area is responsible for its own tasks The most complex achievement of the brain is consciousness