The Brain. PSYCHOLOGY (8th Edition, in Modules) David Myers. Psychology 7e in Modules 1. Module 5. The Brain. The Brain

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1 PSYCHOLOGY (8th Edition, in Modules) David Myers PowerPoint Slides Aneeq Ahmad Henderson State University Worth Publishers, The Brain Module 5 2 The Brain The Brain The Tools of Discovery Older Brain Structures The Cerebral Cortex Our Divided Brain Left Brain-Right Brain 3 Psychology 7e in Modules 1

2 The Brain Techniques to Study the Brain Brain lesion experimentally destroys brain tissue to study animal behaviors after such destruction. Hubel (1990) 4 Clinical Observation Clinical observations have shed light on a number of brain disorders. Alterations in brain morphology due to neurological and psychiatric diseases are now being catalogued. Tom Landers/ Boston Globe 5 Electroencephalogram (EEG) An amplified recording of the electrical waves sweeping across the brain s surface, measured by electrodes placed on the scalp. AJ Photo/ Photo Researchers, Inc. 6 Psychology 7e in Modules 2

3 PET Scan PET (positron emission tomography) Scan a visual display of brain activity that detects a radioactive form of glucose while the brain performs a given task. Courtesy of National Brookhaven National Laboratories 7 MRI Scan MRI (magnetic resonance imaging) uses magnetic fields and radio waves to produce computergenerated images that distinguish among different types of brain tissue. Top images show ventricular enlargement in a schizophrenic patient. Bottom image shows brain regions when a participants lies. Both photos from Daniel Weinberger, M.D., CBDB, NIMH James Salzano/ Salzano Photo Lucy Reading/ Lucy Illustrations 8 Older Brain Structures Brainstem the oldest part of the brain, beginning where the spinal cord swells and enters the skull. Responsible for automatic survival functions. 9 Psychology 7e in Modules 3

4 Medulla [muh-dul-uh] base of the brainstem, controls heartbeat and breathing. Brain Stem Reticular Formation a nerve network in the brainstem that plays an important role in controlling arousal. 10 Thalamus [THAL-uhmuss] the brain s sensory switchboard, located on top of the brainstem. It directs messages to the sensory areas in the cortex and transmits replies to the cerebellum and medulla. Brain Stem 11 Cerebellum The little brain attached to the rear of the brainstem. It helps coordinate voluntary movements and balance. 12 Psychology 7e in Modules 4

5 The Limbic System Limbic System a doughnut-shaped system of neural structures at the border of the brainstem and cerebrum, associated with emotions such as fear, aggression and drives for food and sex. It includes the hippocampus, amygdala, and hypothalamus. 13 Amygdala Amygdala [ah-migdah-la] two almondshaped neural clusters linked to emotion of fear and anger. 14 Hippocampus Structure of the limbic system that is linked to memory. Memory Device: hippo= big campus= place where you learn/remember. 15 Psychology 7e in Modules 5

6 Hypothalamus lies below (hypo) the thalamus; directs several maintenance activities like eating, drinking body temperature, and emotions. Helps govern the endocrine system via the pituitary gland. Hypothalamus 16 Rats cross an electrified grid for self-stimulation, when electrodes are placed in the reward (hypothalamus) center (top picture). When the limbic system is manipulated rat will navigate fields or climb up a tree (bottom picture). Reward Center 17 Sanjiv Talwar, SUNY Downstate The Cerebral Cortex The intricate fabric of interconnected neural cells that covers the cerebral hemispheres. The body s ultimate control and information processing center. 18 Psychology 7e in Modules 6

7 Structure of the Cortex Each brain hemisphere is divided into four lobes, separated by prominent fissures. They are frontal lobes (forehead), parietal lobes (top to rear head), occipital lobes (back head) and temporal lobes (side of head). 19 Functions of the Cortex Motor Cortex area at the rear of the frontal lobes controls voluntary movements. Sensory Cortex (parietal cortex) receives information from skin surface and sense organs. 20 Visual Function Functional MRI scan shows the visual cortex activates as the subject looks at faces. Courtesy of V.P. Clark, K. Keill, J. Ma. Maisog, S. Courtney, L.G. Ungerleider, and J.V. Haxby, National Institute of Mental Health 21 Psychology 7e in Modules 7

8 Auditory Function Functional MRI scan shows the auditory cortex is activate in patients who hallucinate. 22 Association Areas More intelligent animals have increased uncommitted or association areas of the cortex. 23 Language Aphasia is an impairment of language, usually caused by left hemisphere damage either to Broca s area (impaired speaking) or to Wernicke s area (impaired understanding). 24 Psychology 7e in Modules 8

9 Specialization & Integration Brain activity when hearing, seeing, and speaking words 25 The Brain s Plasticity Brain is sculpted by our genes but also by our experiences. Plasticity refers to the brain s ability to modify itself after some type of injury or illness. 26 Our Divided Brain Our brain is divided into two hemispheres. Left hemisphere processes reading, writing, speaking, mathematical, comprehension skills, and thus termed as the dominant brain in the 1960s. 27 Psychology 7e in Modules 9

10 Splitting the Brain A procedure in which the two hemispheres of the brain are isolated by cutting the connecting fibers (mainly those of the corpus callosum) between them. Courtesy of Terence Williams, University of Iowa Corpus Callosum 28 Martin M. Rother Split Brain Patients With the corpus callosum severed, objects (apple) presented in the right visual field can be named. Objects (pencil) in the left visual field cannot. 29 Divided Consciousness 30 Psychology 7e in Modules 10

11 Try This! Try drawing two shapes with both of you hands simultaneously. BBC 31 Non-Split Brains People with intact brains also show left-right hemispheric differences in mental abilities. A number of brain scan studies have shown normal individuals engage their right brain when they engage in a perceptual task, and left brain when carrying out a linguistic task. 32 Brain Organization & Handedness Is handedness inherited? Yes. Archival and historic studies to modern medical studies point that right hand is preferred. This suggests, genes and/or prenatal factors influence handedness. 33 Psychology 7e in Modules 11

12 Is it All Right to be Left Handed? Being a left hander is difficult in a right-handed world. 34 Is it All Right to be Left Handed? The percentage of left-handers decreases sharply in samples of older people (Coren, 1993). 35 Psychology 7e in Modules 12