Use with Atkinson & Hilgard’s Introduction to Psychology 15 th edition Nolen-Hoeksema, Fredrickson, Loftus, Wagenaar ISBN © 2009 Cengage Learning Chapter 2 Biological Foundations of Psychology

Use with Atkinson & Hilgard’s Introduction to Psychology 15 th edition Nolen-Hoeksema, Fredrickson, Loftus, Wagenaar ISBN © 2009 Cengage Learning The Study of the Biological Bases of Psychology Pre-adaptation –Describes the process by which an existing system (e.g. physical disgust/physical pain) is co-opted (“hi-jacked”) in order for new human functions to develop (e.g. moral disgust/response to social exclusion) Nervous system –Divided into Central Nervous System (CNS) and Peripheral Nervous System (PNS) –CNS includes the brain and spinal chord –PNS includes the somatic system and autonomic system

Use with Atkinson & Hilgard’s Introduction to Psychology 15 th edition Nolen-Hoeksema, Fredrickson, Loftus, Wagenaar ISBN © 2009 Cengage Learning Neurons, the Building Blocks of the Nervous System Basic unit of the nervous system = Neuron –Specialized cell that transmits neural impulses or messages to other neurons, glands and muscles Figure 2.2 Schematic Diagram of a Neuron. Arrows indicate the direction of the nerve impulse. Some axons are branched; the branches are called collaterals. The axons of many neurons are covered with an insulating myelin sheath that helps increase the speed of the nerve impulse. (Adapted from Human Anatomy by Anthony J. Gaudin and Kenneth C. Jones. Copyright © 1988 by Anthony J. Gaudin and Kenneth C. Jones. Reprinted by permission of the authors.)

Use with Atkinson & Hilgard’s Introduction to Psychology 15 th edition Nolen-Hoeksema, Fredrickson, Loftus, Wagenaar ISBN © 2009 Cengage Learning Neurons, the Building Blocks of the Nervous System Neurons vary greatly in size and shape Neurons are classified into three categories –Sensory neurons – transmit impulses from receptors to CNS –Motor neurons – carry outgoing signals from CNS to muscles and glands –Inter-neurons – connect sensory and motor neurons

Use with Atkinson & Hilgard’s Introduction to Psychology 15 th edition Nolen-Hoeksema, Fredrickson, Loftus, Wagenaar ISBN © 2009 Cengage Learning Neurons, the Building Blocks of the Nervous System Action Potentials –Information travels along neuron in form of neural impulse called an action potential –Each action potential is the result of movement of electrically charged particles (ions) in and out of neuron –Movement of ions controlled by ion channels - when these are closed the neuron is referred to as “resting” –When a neuron is depolarized above the excitation threshold cell membrane is temporarily unstable, resulting in action potential

Use with Atkinson & Hilgard’s Introduction to Psychology 15 th edition Nolen-Hoeksema, Fredrickson, Loftus, Wagenaar ISBN © 2009 Cengage Learning Neurons, the Building Blocks of the Nervous System

Use with Atkinson & Hilgard’s Introduction to Psychology 15 th edition Nolen-Hoeksema, Fredrickson, Loftus, Wagenaar ISBN © 2009 Cengage Learning Neurons, the Building Blocks of the Nervous System Synaptic transmission and neural coding –All-or-none law – a neuron is either firing action potential, or not, so how can the nervous system code for/represent complexity of experience? –Power of nervous system lies in the complexity of the connections between neurons –Lock-and-key action – the way a neurotransmitter and receptor fit together, which causes a change in permeability of ion channels, either excitatory or inhibitory

Use with Atkinson & Hilgard’s Introduction to Psychology 15 th edition Nolen-Hoeksema, Fredrickson, Loftus, Wagenaar ISBN © 2009 Cengage Learning Neurons, the Building Blocks of the Nervous System Neurotransmitters –More than 70 identified –Acetylcholine – involved in memory and attention and transmits signals between nerve and muscle –Norepinephrine – an increase or decrease in the brain correlates with increase or decrease in mood level –Dopamine – mediates effects of natural rewards (e.g. food) and effects of drugs of abuse

Use with Atkinson & Hilgard’s Introduction to Psychology 15 th edition Nolen-Hoeksema, Fredrickson, Loftus, Wagenaar ISBN © 2009 Cengage Learning Neurons, the Building Blocks of the Nervous System...Neurotransmitters –Serotonin – important role in mood regulation –Glutamate – excitatory in nature – linked with learning and memory –GABA – inhibitory in nature – helps control muscle movement

Use with Atkinson & Hilgard’s Introduction to Psychology 15 th edition Nolen-Hoeksema, Fredrickson, Loftus, Wagenaar ISBN © 2009 Cengage Learning The Organization of the Brain

Use with Atkinson & Hilgard’s Introduction to Psychology 15 th edition Nolen-Hoeksema, Fredrickson, Loftus, Wagenaar ISBN © 2009 Cengage Learning The Organization of the Brain The hindbrain –Medulla Controls breathing & some reflexes which aid upright posture –Pons Important in the control of attentiveness –Reticular formation Network of neurons controlling arousal, also plays role in ability to focus attention –Cerebellum concerned primarily with control of movement & important for learning new motor responses

Use with Atkinson & Hilgard’s Introduction to Psychology 15 th edition Nolen-Hoeksema, Fredrickson, Loftus, Wagenaar ISBN © 2009 Cengage Learning The Organization of the Brain The midbrain –Superior and inferior colliculus Important for transmitting sensory information to brain & in movement control –Substantia nigra Key part of dopamine-containing pathway – deteriorates in Parkinson’s disease

Use with Atkinson & Hilgard’s Introduction to Psychology 15 th edition Nolen-Hoeksema, Fredrickson, Loftus, Wagenaar ISBN © 2009 Cengage Learning The Organization of the Brain The forebrain –Includes cerebrum (split into two hemispheres) and sub-cortical structures –Thalamus Directs incoming information from sense receptors to cerebrum –Hypothalamus Regulates eating, drinking & sexual behavior. Exerts control over ANS & also role in sensation of emotions –Pituitary gland Part of system of glands called endocrine system involved in production of hormones

Use with Atkinson & Hilgard’s Introduction to Psychology 15 th edition Nolen-Hoeksema, Fredrickson, Loftus, Wagenaar ISBN © 2009 Cengage Learning The Organization of the Brain...The forebrain –Limbic system Provides additional control over some instinctive behaviors regulated by central core Hippocampus – special role in recent memory Amygdala – involved in emotional behavior, e.g. fear –Cerebral cortex Receives information from sensory systems; controls motor responses and contains association areas which are concerned with memory, thought and language

Use with Atkinson & Hilgard’s Introduction to Psychology 15 th edition Nolen-Hoeksema, Fredrickson, Loftus, Wagenaar ISBN © 2009 Cengage Learning The Organization of the Brain

Use with Atkinson & Hilgard’s Introduction to Psychology 15 th edition Nolen-Hoeksema, Fredrickson, Loftus, Wagenaar ISBN © 2009 Cengage Learning The Organization of the Brain Mapping the brain –Recent development of sophisticated computer methods allow detailed images of human brain without damaging or distressing patient Methods include computerized axial tomography (CAT or CT), magnetic resonance imaging (MRI), and positron emission tomography (PET)

Use with Atkinson & Hilgard’s Introduction to Psychology 15 th edition Nolen-Hoeksema, Fredrickson, Loftus, Wagenaar ISBN © 2009 Cengage Learning The Organization of the Brain Asymmetries in the brain –Language Understanding about brain mechanisms for language largely derived from studies of patients with brain damage. Aphasia – language deficit caused by brain damage Broca’s area – involved in speech production Wernicke’s area – involved in speech comprehension –Split-brain research The brain normally acts as integrated whole but for some epilepsy patients, the corpus callosum surgically severed - these split-brain patients provide important insights into brain function

Use with Atkinson & Hilgard’s Introduction to Psychology 15 th edition Nolen-Hoeksema, Fredrickson, Loftus, Wagenaar ISBN © 2009 Cengage Learning The Organization of the Brain

Use with Atkinson & Hilgard’s Introduction to Psychology 15 th edition Nolen-Hoeksema, Fredrickson, Loftus, Wagenaar ISBN © 2009 Cengage Learning The Organization of the Brain...Asymmetries in the brain –Hemispheric specialization – split-brain research indicates two hemispheres function differently Left hemisphere – controls ability to express self through language and skilled in mathematical abilities Right hemisphere – comprehends only simple language but highly developed in spatial and pattern sense Specialization does not mean two hemispheres work independently but rather they continually integrate activities

Use with Atkinson & Hilgard’s Introduction to Psychology 15 th edition Nolen-Hoeksema, Fredrickson, Loftus, Wagenaar ISBN © 2009 Cengage Learning The Autonomic Nervous System Autonomic system –System of nerves outside of the brain & spinal chord Autonomic nervous system (ANS) –Activities it controls are autonomous or self-regulating (e.g. digestion & circulation) –ANS has two divisions – sympathetic & parasympathetic –Sympathetic nervous system – active during excitement –Parasympathetic nervous system – associated with rest

Use with Atkinson & Hilgard’s Introduction to Psychology 15 th edition Nolen-Hoeksema, Fredrickson, Loftus, Wagenaar ISBN © 2009 Cengage Learning The Endocrine System Endocrine system –System of glands which secrete hormones to be transported through the bloodstream to act in various ways on cells of different types –Pituitary gland “master gland” which controls secretion activity of other endocrine glands