Lecture Overview • Neural Bases of Behavior • Nervous System Organization • A Tour Through the Brain • Our Genetic Inheritance ©John Wiley & Sons, Inc. 2010 Neural Bases of Psychology • Neuroscience: interdisciplinary field studying how biological processes relate to behavioral & mental processes ©John Wiley & Sons, Inc. 2010 Neural Bases of Psychology (Continued) • Our nervous system consists of neurons (cells responsible for receiving & transmitting electrochemical information). ©John Wiley & Sons, Inc. 2010 Neural Bases of Psychology: The Structure of a Neuron ©John Wiley & Sons, Inc. 2010 Neural Bases of Psychology: Communication Neural • Within a neuron, communication results from an action potential (a neural impulse that carries information along the axon of a neuron). ©John Wiley & Sons, Inc. 2010 Neural Bases of Psychology: Neural Communication (Continued) • Between neurons, communication occurs through transmission of neural information across a synapse by neurotransmitters (chemicals released by neurons that alter activity in other neurons). ©John Wiley & Sons, Inc. 2010 Neural Bases of Psychology: Neural Communication (Continued) • Receiving neurons receive multiple messages from other neurons. These multiple messages then determine if an action potential occurs or not. ©John Wiley & Sons, Inc. 2010 Neural Bases of Psychology: Neural Communication (Continued) • Note how the axon terminals of sending neurons almost completely cover the cell body of the receiving neuron. ©John Wiley & Sons, Inc. 2010 Pause & Reflect: Assessment • What happens to excess neurotransmitters or to those that do not “fit” into the adjacent receptor sites? (The answer appears on the next slide.) ©John Wiley & Sons, Inc. 2010 Pause & Reflect: Assessment • The sending neuron normally reabsorbs the excess (called “reuptake) or they are broken down by special enzymes. ©John Wiley & Sons, Inc. 2010 Neural Bases of Psychology: Applying Psychology to Everyday Life • Key neurotransmitters: • • • • • • Serotonin Acetylcholine (ACh) Dopamine (DA) Norepinephrine (NE) Epinephrine (adrenaline) GABA (gamma aminobutyric acid) • Endorphins ©John Wiley & Sons, Inc. 2010 Neural Bases of Psychology: How Hormones Affect Us • Endocrine System: collection of glands that manufacture & secrete hormones into the bloodstream ©John Wiley & Sons, Inc. 2010 Why Do We Need Two Communication Systems—Neurotransmitters + Hormones? ©John Wiley & Sons, Inc. 2010 Nervous System Organization • Central Nervous System (CNS): brain & spinal cord • Peripheral Nervous System (PNS): all nerves & neurons connecting CNS to the rest of the body – PNS is subdivided into the somatic & autonomic nervous systems – Autonomic nervous system subdivided into sympathetic and parasympathetic nervous systems ©John Wiley & Sons, Inc. 2010 ©John Wiley & Sons, Inc. 2010 Central Nervous System: Terms Important • Neuroplasticity: brain’s lifelong ability to reorganize & change its structure & function throughout the life span • Neurogenesis: process by which new neurons are generated • Stem Cells: immature (uncommitted) cells with the potential to develop into almost any type of cell ©John Wiley & Sons, Inc. 2010 Nervous System Organization: Central Nervous System (CNS) • Brain • Spinal Cord (transmits information into & out of the brain ) ©John Wiley & Sons, Inc. 2010 Nervous System Organization: Central Nervous System (CNS) • The spinal cord is also responsible for involuntary, automatic behaviors called reflexes. ©John Wiley & Sons, Inc. 2010 Nervous System Organization: Peripheral Nervous System (PNS) • PNS connects CNS to the rest of the body & is subdivided into: – Somatic Nervous System (SNS): connects to sensory receptors & controls skeletal muscles – Autonomic Nervous System (ANS): controls involuntary bodily functions & is further subdivided into: »Sympathetic Nervous System (arouses) »Parasympathetic Nervous System (calms) ©John Wiley & Sons, Inc. 2010 Nervous System Organization Anatomy & functions of the sympathetic (arouses) & parasympathetic (calms) nervous systems ©John Wiley & Sons, Inc. 2010 Pause & Reflect: Assessment 1. You touch a hot stove & then immediately & reflexively pull away. This action was controlled by _____. 2. After being startled by the sight & sound of a fierce dog rushing toward you, it is most likely that your _____ is dominant. ©John Wiley & Sons, Inc. 2010 A Tour Through the Brain ©John Wiley & Sons, Inc. 2010 A Tour Through The Brain: Hindbrain • Three key structures & functions of the hindbrain: – Medulla: life survival functions – Pons: respiration, movement, waking, sleeping, & dreaming – Cerebellum: coordination of fine muscular movement, balance, & some aspects of perception & cognition ©John Wiley & Sons, Inc. 2010 A Tour Through The Brain (Continued) • Midbrain: collection of brain structures in the middle of the brain; coordinates movement patterns, sleep, & arousal • Reticular Formation: (archaic term for cells in the hindbrain, midbrain, & brainstem); screens incoming information & controls arousal ©John Wiley & Sons, Inc. 2010 A Tour Through The Brain (Continued) • Forebrain: collection of upper-level brain structures, including the thalamus, hypothalamus, & limbic system – Thalamus: relays sensory messages to the cerebral cortex – Hypothalamus: responsible for drives, hormones, & regulating the body’s internal environment ©John Wiley & Sons, Inc. 2010 Structures of the Forebrain ©John Wiley & Sons, Inc. 2010 A Tour Through The Brain (Continued) • Limbic System: interconnected group of forebrain structures involved with emotions, drives, & memory ©John Wiley & Sons, Inc. 2010 A Tour Through The Brain: Cortex • Cerebral Cortex: surface layer on the left & right cerebral hemispheres; regulates most complex behavior, including sensations, motor control, & higher mental processes ©John Wiley & Sons, Inc. 2010 Cerebral A Tour Through The Brain: Lobes of the Cerebral Cortex (Continued.) ©John Wiley & Sons, Inc. 2010 A Tour Through The Brain: Lobes of the Cerebral Cortex • Frontal Lobes: receive & coordinate messages from other lobes; responsible for motor control, speech production, & higher functions, such as thinking, personality, emotion, & memory ©John Wiley & Sons, Inc. 2010 Pause & Reflect: Critical Thinking • Phineas Gage’s mining accident sent a 13-pound tamping iron through his frontal lobes. How did this affect his short- & longterm behavior & mental processes? ©John Wiley & Sons, Inc. 2010 ©John Wiley & Sons, Inc. 2010 Cerebral Cortex Parietal Lobes: located at the top of the brain direct behind the frontal lobes; responsible for interpreting bodily sensations • Temporal Lobes: located on each side of the brain above the ears; responsible for audition, language comprehension, memory, & some emotional control ©John Wiley & Sons, Inc. 2010 A Tour Through The Brain: Lobes of the Cerebral Cortex (Continued) • Occipital Lobes: located at the back of the brain; responsible for vision & visual perception ©John Wiley & Sons, Inc. 2010 A Tour Through The Brain: Primary Motor Cortex & Somatosensory Cortex ©John Wiley & Sons, Inc. 2010 Pause & Reflect: Critical Thinking • Why are the hands & face on this drawing so large? What do they represent? ©John Wiley & Sons, Inc. 2010 A Tour Through The Brain: Lateralization • The left & right hemispheres of your brain each specialize in particular (but often overlapping) operations. ©John Wiley & Sons, Inc. 2010 Nature or Nurture? • Sex differences in lateralization. Note how activation (red color) is confined to only one hemisphere in the male brain on the left, & how it occurs on both hemispheres in the female brain on the right. ©John Wiley & Sons, Inc. 2010 A Tour Through The Brain: Split-Brain Research • Severing the corpus callosum provides information on the role & functions of the left & right hemispheres. ©John Wiley & Sons, Inc. 2010 A Tour Through The Brain: Split-Brain Research (Continued) ©John Wiley & Sons, Inc. 2010