1 Neuroscience and Behavior Chapter 2

2 History of Mind In 1800, Franz Gall suggested that bumps of the skull represented mental abilities. His theory, though incorrect, nevertheless proposed that different mental abilities were modular. Phrenology Bettman/ Corbis

3 Neural Communication The body’s information system is built from billions of interconnected cells called neurons.

4 Neural Communication Note the similarities in the above brain regions, which are all engaged in information processing. Humans and animals operate similarly when processing information.

5 Neuron A nerve cell, or a neuron, consists of many different parts.

6 Synapse Synapse [SIN-aps] a junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron. This tiny gap is called the synaptic gap or cleft.

7 Neurotransmitters Neurotransmitters (chemicals) released from the sending neuron travel across the synapse and bind to receptor sites on the receiving neuron.

Draw Neural Communication Draw an label two neurons communicating: Work together-> –What labels will you need? –How can you show the neural communication? 8

9 How Neurotransmitters Influence Us Serotonin pathways are involved with mood regulation. From Mapping the Mind, Rita Carter, © 1989 University of California Press

10 Dopamine Pathways Dopamine pathways are involved with diseases such as schizophrenia and Parkinson’s disease. From Mapping the Mind, Rita Carter, © 1989 University of California Press

11 Neurotransmitters

12 Lock & Key Mechanism Neurotransmitters bind to the receptors of the receiving neuron in a key-lock mechanism.

13 Agonists

14 Antagonists

Neurotransmitters Work together: Explain how the following can be linked to neurotransmitters: –Depression –Alzheimer’s Disease –Parkinson’s Disease 15

16 Nervous System Central Nervous System (CNS) Peripheral Nervous System (PNS)

17 The Nervous System

18 Kinds of Neurons Sensory Neurons carry incoming information from the sense receptors to the CNS. Motor Neurons carry outgoing information from the CNS to muscles and glands. Interneurons connect the two neurons. Sensory Neuron (Bipolar) Interneuron Neuron (Unipolar) Motor Neuron (Multipolar)

19 Autonomic Nervous System (ANS) Sympathetic NS “Arouses” (fight-or-flight) Parasympathetic NS “Calms” (rest and digest)

20 Central Nervous System The Brain and Neural Networks Complex Neural Network Interconnected neurons form networks in the brain. Theses networks are complex and modify with growth and experience.

21 Central Nervous System The Spinal Cord and Reflexes Simple Reflex

Nervous System How do the CNS and PNS differ? Give an example of your autonomic nervous system in action and somatic nervous system in action? How does your autonomic nervous system relate to your reflexes? 22

Myelin Repair 23

24 The Endocrine System “slow” chemical communication hormones released by glands.

25 Pituitary Gland “master gland.” Releases hormones that : 1.regulate other glands 2. influence growth

Older Brain Structures Brainstem –Medulla –Thalamus –Reticular Formation Cerebellum 26

27 Brainstem the oldest part of the brain, begins where the spinal cord swells and enters the skull responsible for automatic survival functions.

28 Brainstem - Medulla base of the brainstem that controls heartbeat and breathing.

29 Brainstem- Thalamus the brain’s sensory switchboard, top of the brainstem. directs messages to the sensory areas in the cortex transmits replies to the cerebellum and medulla.

30 Brainstem - Reticular Formation nerve network in the brainstem important role in controlling arousal.

31 “little brain” attached to the rear of the brainstem. helps coordinate voluntary movements and balance. Cerebellum

Older Brain Structures Brainstem –Medulla –Thalamus –Reticular Formation Cerebellum 32 IF YOU ARE RIDING A BICYCLE HOW ARE EACH OF THESE BEING USED?

Techniques to Study the Brain Lesions Clinical Observations Electroencephalogram (EEG) Positron Emission Tomography (PET) Magnetic Resonance Imaging (MRI) Functional MRI (fMRI) 33

34 Lesion experimentally destroys brain tissue study animal behaviors after destruction. Hubel (1990)

35 Clinical Observation - Changes after damaged brain noted Tom Landers/ Boston Globe

36 Electroencephalogram (EEG) amplified recording of the electrical waves sweeping across the brain’s surface measured by electrodes placed on the scalp. AJ Photo/ Photo Researchers, Inc.

37 PET Scan (positron emission tomography) visual display of brain activity detects a radioactive form of glucose while the brain performs a task. Courtesy of National Brookhaven National Laboratories

38 MRI Scan (magnetic resonance imaging magnetic fields and radio waves to produce computer-generated images distinguish among different types of brain tissue Both photos from Daniel Weinberger, M.D., CBDB, NIMH James Salzano/ Salzano PhotoLucy Reading/ Lucy Illustrations

39 border of the brainstem and cerebrum associated with fear, aggression and drives for food and sex hippocampus, amygdala, and hypothalamus The Limbic System

40 Helps to process and form new memories Damage may result in inability to process new memories Hippocampus

41 Amygdala two lima bean- sized neural clusters linked to the emotions of fear and anger.

42 Hypothalamus below (hypo) the thalamus maintenance activities like eating, drinking, body temperature, and control of emotions helps govern the endocrine system via the pituitary gland.

Limbic System What are the parts of the limbic system? If you are riding a bicycle how is each part being used? 43

44 The Cerebral Cortex interconnected neural cells that covers the cerebral hemisphere ultimate control and information processing center

45 Structure of the Cortex four lobes that are separated by prominent fissures. frontal lobe (forehead) parietal lobe (top to rear head), occipital lobe (back head) temporal lobe (side of head)

46 Functions of the Cortex Motor Cortex -rear of the frontal lobes & control voluntary movements Sensory Cortex- front parietal lobe & receives information from skin surface and sense organs

47 Visual Function The functional MRI scan shows the visual cortex is active 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

48 Auditory Function The functional MRI scan shows the auditory cortex is active in patients who hallucinate.

49 Language Aphasia is an impairment of language usually caused by left hemisphere damage either to: Broca’s area (impaired speaking) Wernicke’s area (impaired understanding).

The Cerebral Cortex What is each of the following doing if you are riding a bike? Frontal lobe Parietal lobe Temporal Lobe Occipital lobe Motor cortex Sensory cortex Broca’s area Wernike’s area 50

51 The brain is sculpted by our genes but also by our experiences. Plasticity refers to the brain’s ability to modify itself after some types of injury or illness. The Brain’s Plasticity

52 Our Divided Brain Two hemispheres. Left hemisphere: reading, writing, speaking, mathematics, calculation and comprehension skills Right hemisphere: perceptual tasks, inferences, drawing, perceiving differences, perceiving emotion, causing expression ( left side of face more expressive), social conduct

53 Splitting the Brain -two hemispheres of the brain are isolated by cutting the connecting fibers -mainly those of the corpus callosum Corpus Callosum Martin M. Rother Courtesy of Terence Williams, University of Iowa

54 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.

55 Divided Consciousness

56 Try This! Try drawing one shape with your left hand and one with your right hand, simultaneously. BBC