11 October 2010

Today: Chapter 6 D Structure of the Nervous System

Lab this week: Lecture/demo on Visual System and Data Collection for Somatosensory Physiology

Need access to calf so shorts or loose pants preferable

1QQ # 15 for 8:30 class1. What is an SSRI and what effect does it have on

synaptic transmission?

2. What is an anticholinesterase and what effect does it have on synaptic transmission?

3. Explain how a high frequency of action potentials can result in the release of more synaptic vesicles from the presynaptic terminal.

1QQ # 15 for 9:30 class1. What is MAO and what effect does it have on

synaptic transmission?

2. What role do some astrocytes have in synaptic transmission?

3. Why would it be dangerous to prescribe an SSRI for a person who is already taking an MAOI? (Be sure to define the terms and describe their actions.)

Pharmacological agents intended to act in brain must be able to cross blood-brain barrier.

Who Cares?

Parkinsons Disease

Treatments for Parkinsonism: a) tablets of L-Dopa (which crosses the BBB) unlike Dopamine (which would have widespread effects)b) neuronal transplants (self, fetal, stem cell, pig), c) electrical stimulation NIH Stem Cell Information

Nerves & Ganglia

Tracts, pathways, commissures

Nuclei

Control of digestive functions in quadraplegics via enteric nervous system.

Figure 6.38

Figure 6.39Components of gray matter

Amygdala &Hippocampus

How do we know the functions of various brain regions?

Correlations of deficits of stroke victims with brain regions affected.Selective ablations and spreading necrosis.Selective electrical and chemical microstimulation

a) Neurologist Wilder Penfield & Epilepsyb) Dr. Hettes

Analogy: experiments to discover the function of a battery in a car.

Dorsal roots = sensory (afferent)Ventral roots = motor (efferent, both somatic and autonomic)Gray matter regions of brain and spinal cord“Pinched nerves” and bulging discsAscending and descending axonal tracts in white matter not anatomically delineated.

Atlanta-Boston flightOrigin-DestinationNaming of white matter tracts…..

Explanation for Cervical and lumbar enlargements of spinal cord.

Spinal nerves named for vertebral level.

Using patient’s localization of symptoms with knowledge of dermatomes to determine which spinal nerve is affected by damage.

Epidural injections into region of cauda equina of Lidocaine-like agents to block action potentials in sensory and motor axons without risk of damage to spinal cord.

8

12

5

5

1

Dermatomes

Vision

Hearing & Equilibrium

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