1. The Biological Perspective
Chapter 2

2. Overview of Nervous System
LO 2.1 What are the nervous system, neurons and nerves
Overview of Nervous System
Nervous System - an extensive network of specialized cells that carry information to and from all parts of the body.
Neuroscience – deals with the structure and function of the brain, neurons, nerves, and nervous tissue.
Relationship to behavior and learning.
Why study the nervous system? How could we possibly understand behavior or thoughts without knowing about the incredible organs that allow us to act, think and react. If we can understand how the brain nerves, anglands interact to control feelings thoughts and behaviors, we call begin to truly understand the complex human being.
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3. The Nervous System Nervous System Central Nervous System
Peripheral nervous system
Autonomic
(Involuntary)
Somatic
(Voluntary)

4. The Nervous System
Central Nervous System
Peripheral Nervous System

5. Central Nervous System
LO Brain and spinal cord
Central Nervous System
Central nervous system (CNS) - part of the nervous system consisting of the brain and spinal cord.
Spinal cord - a long bundle of neurons that
carries messages
is responsible for very fast, lifesaving reflexes.
Nervous System
Central Nervous System
Peripheral nervous system
Autonomic
(Involuntary)
Somatic
(Voluntary)
Brain is true core of nervous system makes sence of info received from sences and sends comands out to mussles and the rest of the body
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6. Peripheral Nervous System
LO Somatic and autonomic nervous systems
Peripheral Nervous System
Peripheral nervous system (PNS) - all nerves and neurons that are not contained in the brain and spinal cord but that run through the body itself
Divided into the:
Somatic nervous system
Autonomic nervous system
Nervous System
Central Nervous System
Peripheral nervous system
Autonomic
(Involuntary)
Somatic
(Voluntary)
Refers to things not in the middle
System that enables the brain and spinal chord to communicate with the sensory systems, control muscles and control glands
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7. Autonomic Nervous System
LO 2.4 Somatic and Autonomic nervous systems
Autonomic Nervous System
Autonomic nervous system (ANS) - division of the PNS consisting of nerves that control all of the involuntary muscles, organs, and glands
Composed of:
Sympathetic division Reacts to stressful events and bodily arousal.
Parasympathetic division – restores body to normal functioning after arousal
Nervous System
Central Nervous System
Peripheral nervous system
Autonomic
(Involuntary)
Somatic
(Voluntary)
Functions of this system are more or less automatic
Controls invlutary muscles heart stomach intestines ad glands
Made up of clumps of neurons located on or near the spinal column make up autonomic nervous system
Divided into 2 systems
Sympathetic located near top of rib cage to the waist area middle of spinal column
Called fight or flight system In sympathy with emotions
When stress ends the activity of sympathetic will be resplced with that of parasypathetic The eat drink and rest system reactivates digestion and excretion
Allows body to put back all energy burned
Responsible for all the normal day to day functions
Allows people to deal with stress
Not all organs stimulated digestion of food and excretion of waist are not necessary finctions when dealing with stress thus they are shut down.
Body demands blood sugar.
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8. Autonomic Divisions Sympathetic Parasympathetic Eyes Lungs Heart
Stomach
Blood Vessels

9. Somatic Nervous System
LO 2.4 Somatic and Autonomic nervous systems
Somatic Nervous System
Somatic nervous system - division of the PNS consisting of nerves that carry information from the senses to the CNS and from the CNS to the voluntary muscles of the body.
Nervous System
Central Nervous System
Peripheral nervous system
Autonomic
(Involuntary)
Somatic
(Voluntary)
Activity with shoulders
Made up of the sensory pathway (contains afferent neurons), which is all the nerves carrying messages from the sencses to the central nervous system
And motor pathway, which is all the nerves carrying messages from the central nervous system to the voluntairy or skeletal muscles of the body
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10. Structure of the Neuron
LO 2.1 What are the nervous system, neurons and nerves
Structure of the Neuron
Neuron – cell in the nervous system that receives and sends messages.
Parts of a Neuron
Dendrites - branch-like structures that receive messages.
Soma – contains the nucleus and keeps the cell alive and functioning
Axon - long tube-like structure that carries messages out to other cells
Dendrite = branch looks like branches.
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11. Structure of the Neuron

12. Glial Cells Glial cells - grey fatty cells that:
LO 2.1 What are the nervous system, neurons and nerves
Glial Cells
Glial cells - grey fatty cells that:
Provide support for the neurons to grow
Deliver nutrients to neurons
Produce myelin to coat axons
Glial Cell
Only 10 percent of neurons in brain the other 90 percent are glial cells
-structure on which neurons develop
-hold neurons in place
-cleaning up remains of neurons that have died.
Communicating with neurons and other glial cells.
Provide insulation for neurons.
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13. Myelin Sheath
Myelin - fatty substances that coat the axons of neurons to insulate, protect, and speed up the neural impulse.
Clean up waste products and dead neurons.
Axon does most of the traveling with somas clumped together near spinal chord
Within cable lots of wires coated with plastic bundles of axons travel together in cables called nerves
Multiple sklerosis Faulty immune system body attacks Myelin sheath of axon bundles in spinal chord brain optic nerves, muscles weak, lack of coordination, impaired vision and speech
Myelin

14. The Synapse Space between Axon and Dendrite of a receiving cell
The location where
Neurotransmitters are
released

15. LO 2.2 Neuron communication
Excitatory neurotransmitter - neurotransmitter that causes a receiving cell to fire.
Inhibitory neurotransmitter - neurotransmitter that causes a receiving cell to stop firing.
Excitatory
Inhibitory
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16. How Drugs Work
Drugs similar in shape to neurotransmitters can stimulate receptor cites just like neurotransmitters do
Agonists- mimic or enhance the effects of neurotransmitters
Antagonists- block or reduce the effects of neurotransmitters

17. Neurotransmitters LO 2.2 Neuron communication Menu
Parkinson and neurotransmitter deficit
Acetylcholine in synapses between neurons and muscle cells stimulates skeletal muscles to contract but actually slows contractions in the heart muscle. If acetylcholine receptor cites are blocked then the acetylcholine cant get to the site and the muscle will be incapable of contracting Curane indian blow darts. Black widow spider stimulates release of excessive amounts of acetylcholine causing convulsions and possible death
Dopamine neurotransmitter found within the brain too little releaced in certain area = parkinsons disease too much in certain area = scitzofrenia
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18. Peeking Inside the Brain
LO Study of the brain
Peeking Inside the Brain
Deep lesioning – sending electrical current via a wire, which destroys the brain cells at the tip of the wire.
Electrical stimulation of the brain (ESB) – sending milder electrical current via a wire to explore the activity of the brain
Electroencephalograph (EEG) – Records brain wave patterns produced by electrical activity of the surface of the brain.
One way to studywhat various parts of brain control is to study animals and people with damage to those areas. May use destruction of area or may stimulate the area. Both accomplished by same process.
Thin wire insulated everywhere except tip is sergically insurted into the brains of test animals. If the brain tissue is to be destroyed a strong electrical current sent through
If want to stimulate that area of the brain the current will be milder, causing neurons to react as if received message.
With humans find areas already damaged and test to see what they can do
A harmless way is to recod electrical activity of the surface of brain. Using eeg. Small metal discs called electrodes are placed directly on skin covering skull electrodes connected by wire to computer. The output forms waves that indicate stages of sleep seizures and tummors. And determine which parts of brain are activated durring tasks.
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19. Peeking Inside the Brain
LO Study of the brain
Peeking Inside the Brain
Computed tomography (CT) - brain-imaging method using computer controlled X-rays of the brain.
Magnetic resonance imaging (MRI) - brain-imaging method using radio waves and magnetic fields. FMRI- more detailed
Positron emission tomography (PET) - brain-imaging method in which an injected radioactive sugar shows the activity of the brain with lighter colors indicating more activity.
Eeg only allows to look at activity at surface of brain. Series of ex rays of the brain added by a computer can show stroke damage tumors injuries abnormal brain structure.
CT doesn’t show small details within the brain. A newer technique called magnetic resonance imaging Provides much more detail allows to see effects of very small strokes. Machine generates powerful magnetic field Allow computers to create a three dimensional image of brain.
FMRI- computer tracks changes in oxygen levels of the blood by placing picture of where oxygen goes researchers can see where brain is active.
Researchers who want to see the brain in action may use pet scan Person injected with a radioactive glucose The computer detects activity of brain by looking at which cells are using up the glucose projects activity on monitor can perform tasks
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20. FMRI Scans

21. The Brain Stem Medulla – Forms the lowest part of the brain
LO 2.6 Structures of the bottom part of brain
The Brain Stem
Medulla – Forms the lowest part of the brain
Responsible for life-sustaining functions such as breathing, swallowing, and heart rate.
Driving activity
Medulla
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22. The Brain Stem Pons – Structure above the medulla
Connects the top of the brain to the bottom
Plays a part in sleep, dreaming, left–right body coordination, and arousal.
Pons

23. LO 2.6 Structures of the bottom part of brain
The Brain Stem
Cerebellum - part of the lower brain located behind the Pons
Controls and coordinates involuntary, rapid, fine motor movement.
Controls voluntary movements that happen in rapid succession
Allows to sit in chair
Run walk
Learned reflex’s habits
Cerebellum
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24. LO 2.7 Structures controlling emotion, learning, memory, and motivation
The Limbic System
Limbic system - a group of several brain structures involved in learning, emotion, memory, and motivation.
Thalamus
Hypothalamus
Olfactory bulbs
Amygdala
Hippocampus
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25. LO 2.7 Structures controlling emotion, learning, memory, and motivation
The Limbic System
Hypothalamus- located below the thalamus and directly above the pituitary gland
Regulates body temperature, thirst, hunger, sleeping, waking,
Responsible for motivational behavior
Hypothalamus
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26. The Limbic System
Thalamus - part of the limbic system located in the center of the brain
Relays sensory information from the lower part of the brain to the proper areas of the cortex
Processes some info prior to relaying it
Thalamus

27. The Limbic System
Hippocampus - curved structure located within each temporal lobe
Formation of long-term memories and the storage of memory for location of objects.
Hippocampus

28. The Limbic System
Amygdala - brain structure located near the hippocampus
Responsible for fear responses and memory of fear.
Amygdala

29. The Limbic System
Olfactory bulbs - two projections just under the front of the brain
Receive information from the receptors in the nose located just below.
Olfactory bulbs

30. LO 2.7 Structures controlling emotion, learning, memory, and motivation
The Cortex
Cortex - outermost covering of the brain consisting of densely packed neurons
responsible for higher thought processes and interpretation of sensory input.
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31. The Cortex: Various Primates

32. LO 2.8 Parts of cortex controlling senses and movement
Cerebral Hemispheres
Cerebral hemispheres - the two sections of the cortex on the left and right sides of the brain.
Corpus callosum - thick band of neurons that connects the right and left cerebral hemispheres.
Corpus callosum
Corpus callosum
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33. Kim Peek

34. LO 2.8 Parts of cortex controlling senses and movement
Four Lobes of the Brain
Occipital lobe – section containing the visual centers of the brain.
Primary visual cortex – processes visual information from the eyes.
Visual association cortex – identifies and makes sense of visual information.
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35. Four Lobes of the Brain
Parietal lobes – sections containing centers for touch, taste, and temperature sensations.
Somatosensory cortex – responsible for processing information from the skin and receptors for touch, temperature, body position, and possibly taste.
Coloring activity

36. LO 2.8 Parts of cortex controlling senses and movement
Four Lobes of the Brain
Temporal lobes – areas containing the neurons responsible for the sense of hearing and meaningful speech.
Primary auditory cortex – processes auditory information from the ears.
Auditory association cortex – identifies/ makes sense of auditory information.
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37. Four Lobes of the Brain
Frontal lobes – areas responsible for higher mental processes, decision making, and the production of fluent speech.
Motor cortex – responsible for sending motor commands to the muscles of the somatic nervous system.

38. Four Lobes: Summary

39. Association Areas of Cortex
LO 2.9 Parts of cortex responsible for higher thought
Association Areas of Cortex
Association areas- areas responsible for interpreting information
Broca’s aphasia – result of damage to Broca’s area-Inability to speak fluently, to mispronounce words, and to speak haltingly.
Wernicke’s aphasia – result of damage to Wernicke’s area-Inability to understand or produce meaningful language.
Wernicke’s aphasia
Broca’s aphasia
Makes connections between sensory info coming into the brain and stored memories images and knowledge.
Brokas area devoted to production of speech
Wernckes area- involved in understanding the meaning of words. Speak fluently and pronounce but meaningless.
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40. Association Areas of the Brain
Spatial neglect - condition produced by damage to the association areas of the right hemisphere
Inability to recognize objects or body parts in the left visual field.

41. Split Brain Research Split brain research
LO Left side and right side of brain
Split Brain Research
Split brain research
Study of patients with severed corpus callosum.
Involves sending messages to only one side of the brain.
Demonstrates right and left brain specialization.
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42. Results of Split Brain Research
LO Left side and right side of brain
Results of Split Brain Research
Left side of the brain:
seems to control language, writing, logical thought, analysis, and mathematical abilities,
processes information sequentially,
Right side of the brain
controls emotional expression, spatial perception, recognition of faces, patterns, melodies, and emotions,
processes information globally
Tap finger while saying the alphabet
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