Module 4

1. Module 4 Our Incredible Nervous System

3. Development and Functioning What influences our brains? • Evolution • Birth defects • Brain Damage • Genetic defects

4. Study of the Living Brain • MRI (magnetic resonance) highlights different areas of the brain • fMRI (functional MRI) highlights the active neurons as the brain thinks • PET (positron emmission tomography) • These allow us to understand what parts of the brains have different functions, and where damage has occured

5. Organization of the nervous system Central Nervous System: • Brain and spinal cord • Carries information between the brain and the body Peripheral Nervous System: • Nerves that extend from the spinal cord to carry messages to and from the muscles, glands and sense organs

6. Subdivisions of the Peripheral nervous system Somatic Nervous System: • Nerves connected to sensory receptors or voluntary muscles (ie neck, back, limbs) • Afferent (sensory): nerve fibers carry information to the spinal cord/brain from sensory receptors • Efferent (motor): nerve fibers carry information from the brain/spinal cord to the muscles

7. Subdivisions of the Peripheral nervous system (con’t) Autonomic Nervous System: • Regulates heart, breathing, blood pressure, digestion, mostly involuntary actions • 2 parts: Sympathetic and Parasympathetic

8. Subdivisions of the Peripheral nervous system (con’t) Sympathetic Nervous System • Triggered by threatening/challenging stimuli, increases physiological arousal and prepares body for action Parasympathetic Nervous System • Returns body to calmer, relaxed state and is involved with digestion • Homeostasis means these two systems work together to keep arousal balanced for optimal functioning

9. Comparing the Systems Sympathetic Parasympathetic Pupils constricted/moist Salivation Smooth Dry Decreased rate • Pupils dilated/dry Eyes • Dry Mouth • Goosebumps Skin • Sweaty Palms • Increased rate heart

10. Igor - where is my brain???? Get into your head …

11. Major parts of the brain Forebrain - hemispheres involved in thinking,learning,memory, spoeech and language, emotions,sensations, voluntary movement, planning and decisions Midbrain - reward/pleasure centre stimulatedby food, sex, money, music, attractive faces and drugs: visual and auditory reflaxes, and reticular formation to process sensory information Hindbrain - Pons, Medulla and Cerebellum

12. Major brain stuff, continued Pons: bridge for messages from the spinal cord to brain, also makes sleep chemicals Medulla: controls vital reflexes such as breathing, heart rate and blood pressure Cerebellum: coordinates motor movements (but does not initiate them), timed motor movements, and reflexive learning

13. The Cortex and 4 Lobes of the brain

14. The Cortex • Wrinkled surface of the brain • Majority of neurons found here • Wrinkled to fit many many cells into a small space (paper analogy) • Has four different functional lobes

15. Frontal Lobe • Huge area of cortex • Interprets and performs emotional behaviour, dictates social behaviour,basis of personality,makes decisions, plans and pays attention to environment • Contains motor cortex, which controls voluntary movements • Executive control: like boss of a company

16. Parietal Lobe • Processes sensory information from body parts: touch, location of body in space,temperature sensing and pain, and cognitive functions such as attention to and perception of objects. Also involved in language abilities • Includes somatosensory cortex, which processes sensory information from the body: found next to the motor cortex

17. Temporal Lobe - 4 parts • Involved in hearing, speaking coherently, understanding verbal and written material • Primary Auditory Cortex transforms info from ears into sound sensations • Auditory Association Area takes those sensations and makes them recognizable (ie words/music) • Broca’s Area combines sound into words and arranges them meaningfully (actually in frontal lobe) • Wernicke’s Area is necessary from speaking coherent sentences and understanding speech

18. Occipital Lobe • processes visual information including seeing colour and perceiving and recognizing animals, people and objects • Primary Visual Cortex is at the very back, receives electrcal signals from receptors in the eye and changes them to basic visual sensation (ie light, shadow, texture) • Visual Association Cortex interprets the basic sensations into complete meaningful perceptions such as people, objects or animals

19. - • Broca’s Asphasia • Wernicke’s Asphasia • Visual Agnosia • Neglect Syndrome

20. The Limbic System (old!) • Core of the forebrain • Regulates motivational behaviour such as obtaining food drink and sex; stores memories; also organizes emotional behaviours such as fear, anger and aggression

21. Endocrine System

22. Endocrine System • This system is made up of many glands throughout the body, which secrete various chemicals called hormones which affect organs, muscles, and other glands. • The Hypothalamus controls much of this system by regulating the pituitary gland

23. Are Men and Women Really Different? men & women Problem Solving Emotional Memories Movement and Coordination

24. Parts of Limbic System • Hypothalamus: regulates motivational behaviour, emotional behaviour and secretion of hormones • Amygdala: evaluates emotional significance of stimuli and facial expression • Thalamus:receives sensory information and relays it to different areas of the cortex • Hippocampus: puts fleeting memories into permanent storage in different areas of the brain

25. Functions of Hemispheres • Verbal – left • Mathematical – left • Analytic – left • Self recognition – left • Nonverbal – right • Spatial – right • Holistic – right • Other recognition - right