Chapter 4 – The Brain: Source of Mind and Self

I. The Nervous System: Structure

A. Central Nervous System

1. Brain and spinal cord

B. Peripheral Nervous System

1. Somatic (skeletal) nervous system

2. Autonomic nervous system

a. sympathetic

b. parasympathetic

-- see chart on pg 105 –

II. The Nervous System: Communication

A. The neuron

B. Within-neuron transmission

1. action potentials

2. electrical impulses

3. excitatory and inhibitory messages

3. all-or-none law

C. Between-neuron transmission

1. neurotransmitters

2. needn’t be all-or-none

D. Hormones and endorphins

1. also chemical messengers

2. hormones mostly endocrine-based, released into bloodstream

III. The Brain

A. Structure

1. how can we know various brain structures?

a. brain scans (e.g., PET scans, MRI, etc)

b. study those with brain damage

c. study brain tissue at autopsy of those with specific deficits

d. study effects of lesions/stimulation in animals

B. Localization of functioning (see chart, pg. 125)

1. Brain stem, cerebellum

2. Limbic system

a. hypothalamus: regulation, ANS processes

b. thalamus: “traffic officer”– directs messages to appropriate areas

c. hippocampus: memory

d. amygdala: emotion, assessing danger/threat

3. Cerebral cortex

a. lobes: frontal, parietal, occipital, temporal

b. association areas

c. right and left hemispheres (lateralization)

i. connected by corpus callosum

d. aphasias: Broca’s and Wernicke’s

e. how tissue is allocated