Brain & Biology Part 2 PDF

Brain & Biology: part 2 The Nervous System The central nervous system (CNS) The spinal cord Brain The peripheral nervous system (PNS) TODAY  Announcements Today: ▪ Part 2 Brain & Behaviour ▪ The Nervous System ▪ Quiz 1 (Couse Outline Quiz) and Quiz 2 (on Weeks 1-2) due befo...

Brain & Biology: part 2 The Nervous System The central nervous system (CNS) The spinal cord Brain The peripheral nervous system (PNS) TODAY  Announcements Today: ▪ Part 2 Brain & Behaviour ▪ The Nervous System ▪ Quiz 1 (Couse Outline Quiz) and Quiz 2 (on Weeks 1-2) due before midnight Sun., Sept. 22 BIOLOGY & BEHAVIOUR (PART 2) The central nervous system (CNS) The spinal cord Brain Brain stem Cerebral hemispheres Lobes The peripheral nervous system (PNS)  Why Study the Brain and Nervous System? How does the Which areas of the physical structure brain help us keep of the brain affect our balance? behaviour? What is the physical structure of the brain? Positron emission tomography (PET) A peek inside the brain… Copyright © 2016 by Nelson Education Ltd. 2-5 The Human Nervous System Copyright © 2014 Pearson Canada 2-6 Inc. The Central Nervous System THE SPINAL CORD: AN EXTENSION OF THE BRAIN The spinal cord ▪ a cylinder of neural tissue about the diameter of your little finger  Loaded with glial cells  Protected by bone & spinal fluid ▪ Reaches from the base of the brain, through the neck, and down the hollow centre of the spinal column THE SPINAL CORD: AN EXTENSION OF THE BRAIN The spinal cord ▪ Literally links the body with the brain  Transmits messages between the brain and the peripheral nervous system (PNS)  Sends sensory information to the brain  Messages from brain to muscles, glands, etc. THE PERIPHERAL NERVOUS SYSTEM The nerves connecting the central nervous system to the rest of the body Peripheral Nervous System ▪ Somatic Nervous System All sensory nerves transmitting information from sense receptors to CNS (afferent). All motor nerves relaying messages from CNS to skeletal muscles (efferent). ▪ Autonomic Nervous System  Transmits messages between CNS and body’s internal environment, including organs, glands, blood vessels Autonomic Nervous System Sympathetic Nervous System ▪ Prepares body for action; mobilizes energy resources ▪ “fight or flight” response Parasympathetic Nervous System ▪ Conserves body’s energy; returns body to normal, quiet state after an emergency Autonomic Nervous System, ctd. Copyright © 2014 Pearson Canada 2 - 13 Inc. More than just neurons… (Fig. 2.4) Travelling up the spinal cord… (Fig. 2.5) The hindbrain: the next level ▪ The brain stem  the medulla,  the pons, and  the reticular formation ▪ The cerebellum The brain stem (the hindbrain) ▪ Begins at the site where the spinal cord enlarges as it enters the skull ▪ Handles functions that are vital to our physical survival; damage to it is life- threatening ▪ The most primitive part of the brain ▪ Includes the medulla, the pons, the cerebellum, and the reticular formation The brain stem (hindbrain) Medulla ▪ Controls heart-beat, breathing, blood pressure, coughing, and swallowing ▪ Automatic functions Pons Pons (Latin for “ bridge”) ▪ Above the medulla and at the Medulla top of the brainstem ▪ Influences body movement; sleep & dreaming The brain stem (cont) Reticular formation (“the Gatekeeper”) ▪ Extends through the central core of the brain stem ▪ VIP for attention and arousal ▪ Screens incoming messages  Blocks some; sends others onto higher parts of the brain ▪ Determines how alert we are; on Reticular formation duty during sleep Cerebellum (“little cerebrum”) ▪ 2 hemispheres, like cerebrum ▪ Main tasks:  to execute smooth, skilled movements  to regulate muscle tone and posture ▪ Can be temporarily impaired by alcohol  E.g., enables you to touch your nose or walk a straight line Executive level: Forebrain Forebrain ▪ Thalamus ▪ Hypothalamus ▪ Limbic system ▪ Corpus callosum ▪ Cerebrum (cerebral cortex) Executive level: Forebrain Forebrain ▪ Thalamus ▪ Hypothalamus ▪ Limbic system ▪ Corpus callosum ▪ Cerebrum (cerebral cortex) Thalamus and Hypothalamus Thalamus ▪ The relay station between lower and higher brain centres  all sensory information except smell  Receives pain signals from the body  Regulates sleep cycles Thalamus Thalamus and Hypothalamus Regulates basic biological Hypothalamus needs ▪ One of the most influential structures in the brain ▪ A “master regulator”  regulates hunger, thirst, sexual behaviour, & emotion  also regulates internal body temperature  E.g., makes us shiver Thalamus  Controls the autonomic nervous system (“fight or Hypothalamus flight” The Limbic System Limbic System Limbic system ▪ A group of structures in the brain, including the amygdala and hippocampus ▪ Emotion, memory & motivation The Limbic System: two views Copyright © 2016 by Nelson Education Ltd. 2- 26 The Limbic System: two views The Limbic System Amygdala ▪ plays an important role in emotion, particularly in response to unpleasant or aversive stimuli  E.g., learned fear responses  Recognizing facial expressions signaling fear or anger amygdala The Limbic System Hippocampus ▪ Absoutely essesential in the formation of conscious memory  Especially the ability to store and recall new information  E.g., the name of someone you have just met  Where to find the bathroom in a new house The Cerebral Cortex Cerebral cortex (cerebrum) ▪ Two large hemispheres that cover the upper part of the brain Corticalization ▪ Increase in size and wrinkling of the cortex Copyright © 2016 by Nelson Education Ltd. 2- 30 The Cerebrum ▪ Responsible for all “higher” cognitive functions, e.g.,  logic,  problem solving,  language comprehension and production Side view Top view The Cerebrum Corpus callosum ▪ a thick band of nerve fibres which connects them ▪ Allows communication between the 2 halves Copyright © 2016 by Nelson Education Ltd. 2-33  The Cerebrum Composed of two cerebral hemispheres  Right cerebral hemisphere  Left cerebral hemisphere Lateralization Specialization of cerebral hemisphere. Cerebral Hemispheres: Lateralization Left Hemisphere Right Hemisphere Controls right side of body. Controls left side of body. Coordinates complex movements. Specialized for visual-spatial Controls production of speech, written perception. language. Specialized for understanding nonverbal behaviour. Copyright © 2014 Pearson Canada 2 - 35 Inc. Another view… Copyright © 2016 by Nelson Education Ltd. 2- 36 Corpus Callosum 2- Copyright © 2014 Pearson Canada Inc. 37 The Cerebrum Motor cortex ▪ controls voluntary body movement Somatosensory cortex ▪ where touch, pressure, temperature, and pain register in the cerebral cortex Motor Cortex and Somatosensory Cortex Copyright © 2014 Pearson Canada 2 - 39 Inc. Language: speech & comprehension Broca’s area ▪ Area of the brain that controls the production of speech sounds (frontal lobe) Wernicke’s area ▪ Involved in the comprehension of speech, and the ability to organize coherent speech (temporal lobe) Language: speech & comprehension ▪ Broca’s Aphasia Impairment in ability to physically produce  speech sounds.  In extreme cases, inability to speak.  Caused by damage to Broca’s area. ▪ Wernicke’s Aphasia  Aphasia from damage to Wernicke’s area.  Person’s spoken language is fluent.  Content is either vague or incomprehensible to listener. Language: speech & comprehension Copyright © 2014 Pearson Canada 2 - 42 Inc. Four lobes of the cortex: Copyright © 2014 Pearson Canada 2 - 43 Inc. The Frontal Lobes Moving, Speaking, Thinking At front of brain. Extends to top centre of skull. Contains motor cortex, Broca’s area Phineas Gage https://www.youtube.com/watch?v=yXbAMHzYGJ0 The Parietal Lobes Parietal Lobes: Sense of Touch Body awareness, spatial orientation. Lobes contain somatosensory cortex. The Occipital Lobes Occipital Lobes: Sight Contain primary visual cortex. Where vision registers. involved in reception and interpretation of visual information. Temporal Lobes The Temporal Lobes: Hearing Lobes contain primary auditory cortex. Wernicke’s area (left lobe) and areas for interpreting auditory information. Want to review those brain parts again? ▪ In my opinion, one of the best review clips ever… ▪ https://www.youtube.com /watch?v=XAurv6mAWKM