1. Chapter 4: The Nervous
System

2. Components of the Nervous
System
Homeostasis
Humans must maintain their environment within certain limits
Temperature
Acidity
Water content
Sodium content
Glucose concentrations
Psychoactive drugs impact homeostasis

3. The Nervous Systems
 Somatic nervous system (SNS)
 Sensory information
 Voluntary actions
 Autonomic nervous system (ANS)
 Sympathetic branch
 Parasympathetic branch
 Central nervous system (CNS)
 Brain
 Spinal cord

4. The Brain: Major Structures
Cerebral cortex**
Cerebellum
Limbic system**
Brain stem**

5. Cerebral Cortex
 “Gray Matter”
 Maintain cognitive functioning
 Divided into lobes:
 Parietal
 Frontal
 Temporal
 Occipital

6. Limbic System
 Emotional brain
 Drives
 Pleasure
 Formation of memories
 Nucleus Accumbens
 Central part of limbic system
 “Reward Pathway”

7. Brain Stem
 Extension of spinal cord
 Small but “mighty”
 All information from body to
major parts of brain goes
through brain stem

8. Chemical Theories of Behavior
 Variations in behavior
explained through changes
in brain chemistry
 Historical and cultural perspectives
 Monoamine theory of mood
 Issue of experimental support
 Brain imaging techniques
 Types
 Reactions