Module 4 Our Incredible Nervous System

Development and Functioning What influences our brains?  Evolution  Birth defects  Brain Damage  Genetic defects What influences our brains?  Evolution  Birth defects  Brain Damage  Genetic defects

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

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 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

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 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

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 Autonomic Nervous System:  Regulates heart, breathing, blood pressure, digestion, mostly involuntary actions  2 parts: Sympathetic and Parasympathetic

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 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

Comparing the Systems Sympathetic  Pupils dilated/dry Eyes  DryMouth  GoosebumpsSkin  SweatyPalms  Increased rateheart  Pupils dilated/dry Eyes  DryMouth  GoosebumpsSkin  SweatyPalms  Increased rateheart Parasympathetic  Pupils constricted/moist  Salivation  Smooth  Dry  Decreased rate  Pupils constricted/moist  Salivation  Smooth  Dry  Decreased rate

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

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 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

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 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

The Cortex and 4 Lobes of the brain

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  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

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  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

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  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

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  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

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  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

--  Broca’s Asphasia  Wernicke’s Asphasia  Visual Agnosia  Neglect Syndrome  Broca’s Asphasia  Wernicke’s Asphasia  Visual Agnosia  Neglect Syndrome

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  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

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  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

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

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  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

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