1. Introduction to the nervous System

2. Divisions of the nervous system
Central nervous system - encased in bone
Spinal cord
brain
Peripheral nervous system – everything else
Somatic nervous system – voluntary control
Sensory nerves
Motor nerves
Autonomic nervous system – no conscious control
Sympathetic nervous system – fight or flight response
Parasympathetic nervous system -

3. The spinal cord

4. Function of the spinal cord
White matter – nerve fibers running to and from the brain
Gray matter – neurons and synapses, mediates reflexes
Dorsa horn – sensory
Ventral horn - motor

5. The Brain

6. Hindbrain
Medulla – involved with autonomic system –regulating breathing and vomiting, etc.
Reticular activating and raphe system – activates the brain maintaining arousal or reduces arousal for sleep
Locus coeruleus – mood control and alerting response
Cerebellum – coordination of voluntary movements, eye saccades, and simple learning

7. Basal ganglia Important for the control of voluntary movement
Memory for spatial location
Provides feedback to cortex about movement and initiation of movement

8. Periaqueductal Gray
Carries information about pain from spinal cord to the cortex
Punishment center8

9. Limbic System Hypothalamus Hippocampus Septum Amygdala
Controls eating drinking, sexual, etc. behaviors
Hippocampus
Formation of new memories
Septum
Emotion and emotional memories
Amygdala
Implements aggressive behavior
Active in fear conditioning

10. Cortex
Posterior and central areas primarily concerned with sensory and motor functions
Frontal lobe – inhibition of behaviors, expression of emotion, availability of rewards
Prefrontal areas
Orbitofrontal – learning reward associations
Prefrontal working memory and thinking
Dorsolateral – maintenance of attentional demands of a task
Anterior cingulate – mediates attention, inhibition of dominant behaviors

11. Development of the Nervous System
Formation of neurons – neurogenesis- largely prenatal
Majority of cells develop in first 3 months gestation - up to 150,000 cells per minute easily disrupted by chemicals and radiation
Migration pre and post natal
Cells move from where they were formed to their target area
They move either toward or away from chemicals released by areas of the brain
Interconnections develop – largely postnatal
Programmed cell death

12. Methods of investigating drug effects on the nervous system
Electroencephalograms (EEG): Electrodes are attached to the subject’s scalp, and the device records the patterns of brain waves.
Event-Related Potentials: The momentary changes in electrical activity of the brain when a particular stimulus is presented to the subject.

13. Methods of investigating drug effects on the nervous system (cont.)
Imaging Technology
Magnetic Resonance Imaging (MRI): Gives clear pictures of the structure of the brain.
Functional MRI: Image shows regions of the brain with heightened neural activity, with different colors reflecting high or low levels of blood flow, oxygen uptake, and the like.
PET scans- use radioactive labels attached to glucose