CNS Overview - Prunuske Flashcards
Define consciousness:
State of being both awake and aware
What is wakefulness?
Intact arousal & ability to open eyes
What is awareness?
Experience of thoughts, memories and emotions
What type of lesion most commonly causes locked-in syndrome?
Lesion of ventral pons.
What usually happens when the cortex is injured?
No loss of consciousness (awareness happens in the cortex)
What usually happens when the midbrain is injured?
Loss of consciousness
What is a coma?
Not aware, awake
- No spontaneous eye movement
- Caused by damage to BOTH hemispheres, brainstem or thalamus
- Unarousable
- Absent motor function
- May have spinal reflexes only
- Can’t see, hear or have emotions
What is persistent vegetative state?
- Eyes can be open
- Unresponsive
- Sleep-wake cycles
- No pain, awareness
- May smile, grimace, reflexively grip hand
- No thoughts, memories, emotions, or intentions
- Usually caused by damaged cortex and/or thalamus
- Can’t see, hear or somatosensory perception(pain) (or diminished)
What is minimally conscious state (MCS)?
- After drinking, impaired by drugs and other substances
- Some sleep wake cycles
- Spontaneous eye opening
- Partial awareness
- May follow commands & communicate at times
- May track finger, localize painful stimuli
- Can hear, see, somatosensory perception intact (pain)
- Emotions variably intact
What is Locked-In Syndrome?
- Normal sleep, wake cycles
- Spontaneous eye opening
- Normal awareness
- Quadraplegia, anarthria
- Ability to blink or move eyes up and down
- Can hear, see and feel emotions
- Somatosensory perception (pain) not intact
- Often caused by damage to bilateral ventral pons
What are the three parts of the forebrain?
Cerebral cortex, basal ganglia, thalamus
What is the function of the basal ganglia?
- Coordinates choice of mutually exclusive skeletal muscle actions
- Does not have distinct shape 0 just sets of ganglia
- People with basal ganglia troubles end up with movement disorders (parkinsons)
- Operational learning (links to limbs: system to associate emotions, goals, motivations, movement disorders)
- Dysfunction leads to movement disorders
- Big link between basal ganglia and limbic system (emotion)
What is the function of the thalamus?
-Interpret/modulate sensory input to cortex
-Change input ot cortex based on arousal, sleep, vigilance, etc.
-Role in attention to parts of feature of sensory environment
(helps process divergent sensory information)
-Damage to it can result in chronic neuropathic pain
What is the function of the brainstem?
-Controls vital life functions
Function: Homeostasis, life-sustaining functions, cranial nerve nuclei
Parts: Midbrain, Pons, Medulla
What is the function of the midbrain?
- Vertical eye movements
- Pupil control
- Posture & Locomotion
- Non-rapid eye movement
- Level of arousal
