The document provides an overview of the nervous system, detailing its divisions, including the central and peripheral systems, and their specific functions such as voluntary and autonomic control. It elaborates on key brain structures like the hindbrain, limbic system, and cortex, highlighting their roles in regulating behavior, movement, and memory formation. Additionally, methods for investigating drug effects on the nervous system, including EEG, MRI, and PET scans, are described.

1. 1
Introduction to the nervous
System

2. 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. 3
The spinal cord

4. 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. 5
The Brain

6. 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. 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. 8
Periaqueductal Gray
• Carries information
about pain from spinal
cord to the cortex
• Punishment center8

9. 9
Limbic System
• Hypothalamus
– 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. 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. 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. 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. 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