What is the relationship between the two divisions of the autonomic nervous system, and the signific

1
What is the relationship between the two
divisions of the autonomic nervous system, and
the significance of dual innervation?
2
Dual Innervation

• Most vital organs receive instructions from both
  sympathetic and parasympathetic divisions
• 2 divisions commonly have opposing effects

3
Autonomic Plexuses

• Nerve networks in the thoracic and abdominopelvic
  cavities
• formed by mingled sympathetic postganglionic
  fibers and parasympathetic preganglionic fibers

4
6 Autonomic Plexuses

• Cardiac plexus
• Pulmonary plexus
• Esophageal plexus
• Celiac plexus
• Inferior mesenteric plexus
• Hypogastric plexus

5
Why is autonomic tone important?
6
Autonomic Tone

• ANS function
• if nerve is inactive under normal conditions, can
  only increase activity
• if nerve maintains background level of activity,
  can increase or decrease activity
• Significant where dual innervation occurs
• 2 divisions have opposing effects
• More important when dual innervation does not
  occur

7
What is the hierarchy of interacting levels of
control in the autonomic nervous system?
8
Visceral Reflexes

• Provide automatic motor responses
• Long or short reflexes
• Can be modified, facilitated, or inhibited by
  higher centers, especially hypothalamus
• All polysynaptic
• Consensual light reflex
• Pupillary reflex

9
Visceral Reflex Arc

• Receptor
• Sensory neuron
• Processing center
• interneurons
• 2 visceral motor neurons

10
Characteristics of Higher-Order Functions

• Require cerebral cortex interaction with other
  parts of brain
• Involve conscious and unconscious information
  processing
• Not part of programmed wiring of brain
• Can adjust over time

11
How are memories created, stored, and recalled?
12
Memories

• Are stored bits of information gathered through
  experience
• Fact Memories
• specific bits of information
• Skill Memories
• learned motor behaviors
• Incorporated at unconscious level with repetition

13
2 Classes of Memories

• ShortTerm Memories
• can be recalled immediately
• small bits of information
• Long-Term Memories
• can last entire lifetime
• Secondary or Tertiary
• Amnesia

14

• Memory Consolidation
• Conversion from short-term to long-term memory
• Amygdaloid body and hippocampus
• are essential to memory consolidation

15
What is the difference in the levels of
consciousness and unconsciousness?
16
States of Consciousness

• Many gradations of both states
• Degree of wakefulness indicates level of ongoing
  CNS activity

17
What are the characteristics of brain activity
associated with the different levels of sleep?
18
2 Levels of Sleep

• Characteristic patterns of brain wave activity
• deep sleep
• REM

Figure 1614a
19
Significance of Sleep

• Has important impact on CNS
• Minor changes in physiological activities of
  organs and systems
• Protein synthesis in neurons increases during
  sleep
• Extended periods without sleep lead to
  disturbances in mental function

20

• Awakening from sleep
• Function of reticular formation
• Extensive interconnections with sensory, motor,
  integrative nuclei, and pathways along brain stem
• State of consciousness is determined by complex
  interactions between reticular formation and
  cerebral cortex

21
Reticular Activating System (RAS)

• brain stem component
• Diffuse network in reticular formation
• Extends from medulla oblongata to mesencephalon

22
Reticular Activating System (RAS)
Figure 1615