Title: Neuroscience
1 Chapter 3 Neuroscience Biological Foundations
2The Nervous System
CNS
3Neurons
- Neurons are composed of
- Cell body (soma) directs actions of the cell
- Dendrites extensions that receive information
- Axon extends from cell body, carries electrical
potential, sends a chemical message to adjacent
neurons via terminal buttons
4The Action Potential
5At rest, the inside of the neuron negative
relative due to a higher concentration of
positively charged ions outside the neuron.
When stimulated, sodium channels open and
positively charged sodium ions rush into the
axon, depolarization a small region within the
axon.
The region of depolarization causes nearby sodium
channels to open. Just after the sodium channels
close, the potassium channels open wide, and
potassium exits the axon, repolarizing the tissue
just behind the action potential.
This process continues as a chain-reaction along
the axon. The influx of sodium depolarizes the
axon, and the outflow of potassium repolarizes
the axon.
The sodium/potassium pump restores the resting
concentrations of sodium and potassium ions
http//intro.bio.umb.edu/111-112/112s99Lect/neuro_
anims/a_p_anim1/WW3.htm
6Myelinated Axons
7Neurons are for Communicating
8Synapse
9Neurotransmitters
- Serotonin affects mood, sleep, sensory
perception, and other functions, may play a role
in psychological disorders like depression - Acetylcholine involved in memory, muscle
action, sleep, emotions, those w/ Alzheimers
have lower levels - Dopamine affects movement, attention, memory,
learning, plays role in addiction - Norepinephrine affects learning, memory,
emotions, eating, alertness, etc. - Epinephrine emotions, memory storage
10Nicotine is an acetylcholine agonist
Curare is an acetylcholine antagonist
11The Nervous System
CNS Central Nervous System PNS Peripheral
Nervous System
12Peripheral Nervous System
- PNS includes all nerves outside the brain and
spinal cord - Broken down into somatic and autonomic nervous
systems - Somatic NS carries sensory messages to brain and
motor commands to the muscles
Somatic Nervous System
13Peripheral Nervous System
- Autonomic N.S. regulates automatic body functions
(heart rate, breathing) - Sympathetic Fight or Flight
- Parasympathetic Active during digestion
14Autonomic Nervous System
Parasympathetic
Sympathetic
calms
arouses
15The Spinal Cord
16Midline Brain ViewLower Level Brain
Structures-oldest part of the brain
- 3 major Brain Stem Structures
- Pons
- Medulla
- Reticular Formation
17Midline Brain View
Corpus Callosum connects 2 brain hemispheres
Thalamus Sensory relay area
Hypo- Thalamus 4 Fs Feeding, Fleeing,
Fighting Mating
Cere- Bellum - Smoothes movements
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19the cerebral cortex...
204 lobes of the cerebral cortex Frontal,
Parietal, Occipital, Temporal (F-POT)
Frontal Lobes Motor Control, Speech Production,
Higher Functions
Brocas Area
21Phineas Gage 1823 - 1861
224 lobes of the cerebral cortex Frontal,
Parietal, Occipital, Temporal (F-POT)
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25Occipital Lobes
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28Summary of Hemispheric Specializations-lateral
ization
29Studying the Brain
- Lesion studies a brain region is destroyed and
behavior is observed - Lesions of hypothalamus in animals ---gt
overeating - Strokes interrupt blood flow in brain ---gt damage
brain
30Studying the Brain
- Electrical Recording overall brain wave
activity monitored by electroencephalograph (EEG) - Electrical Stimulation of the Brain (ESB)
31Studying the Brain
- Imaging techniques allow the living brain to be
studied for its activity during behavior - CT scans (computed tomography) used to detect
brain structure abnormalities in people w/ mental
illness
left temporal tumor
meningitis
32Studying the Brain
- PET scans use radioactive glucose to assess brain
activity
Control Ecstasy User
33Studying the Brain
MRI Scan of Tumor in Speech Center
- MRI scans generate 3D views of the human brain
- fMRI faster version of MRI
MRI for Face Recognition in Normal Volunteer gt