Neuroscience, Tutorial, for Masters Level Neuroscience Students, Neurobiology, Neurochemistry, Neurophysiology, Neuropsychology, Hypothalamus Basal Ganglia

1. Chapter 2
Neuroscience

2. Brain and Mind
T h e P e r s o n
T h e B r a in
P h y s i c a l
T h e M i n d
P s y c h o l o g i c a l

3. Topics to Explore
1. The Neuron
2. The Peripheral Nervous System
3. The Central Nervous System

4. Part One
Neuron

5. Neuron and Its Parts
Neuron: Individual nerve cell; 100 billion in brain
- Dendrites: Receive messages from other neurons;
have thousands of branches
- Soma: Cell body; metabolic center of neuron; contains
genetic material
- Axon: Carries information away from the cell body;
longest part of neuron
- Axon Terminals: Branches that link the dendrites and
soma of other neurons
- Synaptic Gap: Space between the end of the axon of
one neuron and the dendrites of an adjacent neuron

6. Picture of a Neuron

7. The Nerve Impulse
• Resting Potential: Electrical charge of an inactive neuron
• Threshold: Trigger point for a neuron’s firing
• Action Potential: Nerve impulse

8. Resting Potential
Resting Potential: Tiny charge between inside & outside of
neuron
• Created by electrically charged particles (ions)
- Some concentrated outside the cell (sodium and
chloride ions)
- Some concentrated inside the cell (Potassium ions)
• How is the charge maintained?
- Sodium-potassium pump
- Selectively permeable cell membrane

9. Action Potential
Action potential: Change in potential, primarily because
of messages from other neurons
• Excitatory messages: Cell loses the negative charge;
Depolarization
• Inhibitory messages: Cell becomes more negatively
charged; Hyperpolarization

10. Resting vs. Action Potential

11. Graphic: Action Potential

12. Graphic: Action Potential

13. Graphic: Synaptic Gap

14. Neurotransmitters
Neurotransmitters: Chemicals that alter activity in
neurons; brain chemicals. Messages from one neuron to
another pass over the synapse, the microscopic gap
between neurons
Receptor Site: Areas on the surface of neurons and other
cells that are sensitive to neurotransmitters
Antagonist: drug that decreases activity of a neurotrans-mitter

15. Some Neurotransmitters
• Acetylcholine: involved in learning, memory, and muscle
contractions. Botulism toxin prevents release of acetylcholine,
resulting in paralysis
• Dopamine: involved in arousal, mood, and movement. In
Parkinson’s, receptors in brain fail to react to dopamine, leading to
tremors, rigidity and problems initiating movement
• Serotonin and Norepinephrine: involved in arousal and mood.
Cocaine blocks re-uptake of both neurotransmitters, resulting in “high”
• GABA (gamma-aminobutyric acid): main inhibitory neurotrans-mitter;
lowers arousal and anxiety
• Endorphins: lower pain perception. Morphine and heroin bind to
endorphin receptors, increasing endorphin activity.

16. Nerves and Neurons
• Nerves: Large bundles of neurons
• Myelin: Fatty layer of tissue that coats axons
• Multiple Sclerosis (MS) occurs when myelin layer is
destroyed; numbness, weakness, and paralysis occur

17. A Little Exercise
Demonstration of the speed
of a neural impulse.

18. An Organizational Pause
Organization of
the CNS

19. Major Sections of
the Nervous System
• Central Nervous System (CNS): Brain and spinal cord
• Peripheral Nervous System: All parts of the nervous
system outside of the brain and spinal cord
- Autonomic System: Serves internal organs and glands;
controls automatic functions such as heart rate and blood
pressure
- Somatic System: Links spinal cord with skeletal
muscles and sense organs; controls voluntary behavior

20. Organization of Nervous System

21. Graphic: Nervous System

22. Part 2
The Peripheral Nervous System
See in class!
• The Autonomic Nervous System
• The Somatic Nervous System

23. Divisions of Autonomic System
• Sympathetic: Arouses body; emergency system
• Parasympathetic: Quiets body; most active after an
emotional event

24. Functions of
Autonomic Nervous System

25. Three Components of Emotion
• Physical component: state of physiological
arousal triggered by autonomic nervous system
• Behavioral component: outward expression of the
emotion, including facial expression & behavior
• Cognitive component: appraisal of the situation to
determine which emotion we are experiencing and
why

26. James-Lange Theory of Emotion

27. Cannon-Bard Theory of Emotion

28. Schachter-Singer Theory

29. Comparison of
Three Theories of Emotion

30. Somatic Nervous System
• Motor Nervous System: transfers messages from CNS
to control function of voluntary muscles
• Sensory Nervous System: transfers messages from
sensory organs to CNS; brings information from outside
the body to the brain to be processed

31. Structures in Somatic System
• Sensory neuron: neuron that transmits information
from sensory organ to CNS
• Motor neuron: neuron that transmits information from
CNS to voluntary muscle
• Connector neuron: neuron in spinal cord connecting
sensory and motor neurons to form reflex arc.
• Reflex: An innate, automatic motor response to a
specific sensory stimulus

32. Graphic: Somatic Nervous System

33. Motor & Somatosensory Areas
in Cerebral Cortex

34. Motor Homunculus
“homunculus” =
“a diminutive human
being”

35. Somesthetic Homunculus

36. A Little Exercise
A demonstration of the somatosensory
system, using toothpicks and little rulers.

37. Part 3
The Central Nervous System
See in class! • The Spinal Cord
• The Brain
- The Central Core
- The Limbic System
- The Cerebral Cortex

38. The Spinal Cord
• Spinal Nerves: 31 of them; carry sensory and motor
messages to and from the spinal cord
• Cranial Nerves: 12 pairs that leave the brain directly;
also work to communicate messages
• Spinal cord functions to connect peripheral nervous
system to the brain

39. The Central Core
(aka the “old brain”)
• Medulla: Connects brain with the spinal cord and controls vital
life functions such as heart rate and breathing
• Cerebellum: Regulates posture, muscle tone, muscular
coordination, and procedural learning
• Reticular formation: Associated with levels of arousal and
consciousness, as well as some reflexes (breathing, coughing,
sneezing, vomiting)
• Thalamus: serves as a relay station for incoming sensory
Information
• Basal ganglia: involved in physical movement

40. Graphic: Central Core

41. The Limbic System
At the top border (limbus in Latin) of the brain stem.
•Hypothalamus: controls pituitary gland (directing activity of
endocrine system) and autonomic nervous system; involved in
basic drives (eating, drinking, sex)
• Hippocampus: involved in formation of memories
• Amygdala: involved in regulating emotional experiences,
particularly initial emotional responses

42. Graphic: Limbic System

43. Neocortex
• Cerebral Cortex: Outer layer of the cerebrum
• Cerebrum: Two large hemispheres that cover upper part
of the brain
• Corticalization: Increase in size and wrinkling of the
cortex
• Cerebral Hemispheres: Right and left halves of the
cerebrum
• Corpus Callosum: Bundle of fibers connecting cerebral
hemispheres

44. Graphic: Relative Size

45. Graphic: Corpus Callosum

46. Left & Right Hemispheres

47. Left Brain/Right Brain
• About 95 percent of our left brain is used for language
• Left hemisphere better at math, judging time and rhythm,
and coordinating order of complex movements
- Processes information sequentially
• Right hemisphere good at perceptual skills, and at
expressing and detecting other’s emotions
- Processes information simultaneously

48. Graphic: Left vs. Right

49. Lobes of the Neocortex
• Occipital Lobe: Back of brain; vision center
• Parietal Lobe: Just above occipital; bodily
sensations such as touch, pain, and temperature
(somatosensory area)
• Temporal Lobe: Each side of the brain; auditory and
language centers
• Frontal Lobe: Movement, sense of smell, higher
mental functions; contains motor cortex; controls motor
movement

50. Graphic: Lobes