exam 3 neuro- chapter 12 Limbic System and Reticular Formation

components of the limbic system

• Cingulate gyrus

• Parahippocampal gyrus

• Hippocampus

• Amygdala

• Hypothalamus

• Fornix

• Mammillary bodies

• Anterior thalamus

• Olfactory regions

components of the reticular formation

Network of nuclei throughout the brainstem, including the reticular activating system (RAS).

Hippocampus

Formation/consolidation of new memories

Amygdala

Emotion, emotional learning and memory

Hypothalamus

Homeostasis and autonomic control

Cingulate gyrus

Emotion, motivation, attention

Fornix

Connects hippocampus with other limbic structures

Mammillary bodies

Memory circuits

Thalamus

Relay of information

Reticular formation

Arousal, sleep, motor and autonomic regulation

Limbic system

- Connected cortical and subcortical structures.

- Responsible for homeostasis, olfaction, memory, and emotion. (HOME)

Homeostasis

controlled by hypothalamus

• Maintains stable internal body conditions.

• Regulates temperature, hunger, thirst, blood volume, reproduction, and circadian rhythms.

• Controls sympathetic and parasympathetic activity.

Olfaction

controlled by olfactory regions and medial temporal limbic structures

• Processes smell.

• Connections with amygdala and hippocampus explain associations between smells, emotions, and memories.

Memory

controlled by hippocampus and connected regions

3 Primary Memory Subsystems:

• working

• declarative (explicit)

• non-declarative (implicit)

  

Working Memory

A system for holding and manipulating information temporarily, crucial for tasks like problem-solving and tracking information.

Declarative (Explicit) Memory:

Memory for facts and events that can be consciously recalled, including semantic (facts) and episodic (events) memory.

Nondeclarative (Implicit) Memory:

Unconscious memory for skills, habits, and procedures learned through practice, like riding a bike or tying shoes.

Emotions

controlled by amygdala

• Emotional regulation and decisions.

• Emotional learning and memory.

• Fear, anxiety, anger, reward/punishment.

• Amygdala communicates with hypothalamus to produce autonomic emotional responses.

What are disorders of consciousness?

Consciousness requires wakefulness and awareness

TBI can cause disorders of consciousness that impact these functions

• Unresponsive wakefulness syndrome (Wakefulness without clear awareness)

• Minimally conscious state: (Limited but detectable awareness.)

• Emergence from minimally conscious state: (Recovery of functional communication or object use.)

What causes disorders of consciousness?

traumatic brain injury and damage/disruption to brain systems regulating arousal and awareness.

what makes up the peripheral nervous system?

All nerves except brain and spinal cord

Peripheral nervous system functions

Cranial and Spinal nerves makeup 2 major systems:

• Somatic Nervous System

  • Voluntary control

• Autonomic Nervous System

  • Involuntary control (organs)

    • Sympathetic System

    • Parasympathetic System

components of autonomic nervous system

Sympathetic: Fight or flight; increases heart rate, reduces digestion.

Parasympathetic: Rest and digest; decreases heart rate, increases digestion.

difference between CNS and PNS

• CNS: Brain and spinal cord.

• PNS: All nerves and ganglia outside the brain and spinal cord.

The CNS processes/integrates information; the PNS carries sensory information to the CNS and motor commands away from it.