Final 6 (Cortical States) Flashcards
What are the three A’s associated with level of consciousness
- Alertness
- Attention
- Awareness
Level of consciousness is sustained by _______________________.
Conscious system networks
Conscious system networks mediate _____________, _________________, and __________________.
Conscious system networks mediate arousal, alertness and attention
Four key brain areas are involved in consciousness, what are they?
- Upper brainstem
- Thalamus
- Hypothalamus
- Basal forebrain
Which level of consciousness needs normal brainstem & diencephalic arousal circuits, and the cortex?
Alertness
Attention requires the same circuits as alertness + ________________________
Fronto-parietal association cortex
The ability to combine various higher-order forms or information from disparate regions into a unified and efficient summary of mental activity (which can be remembered at a later time)
Awareness
What are the brain centers involved in alertness?
- Brainstem
- Diencephalon
- Cortex
Alertness depends on…
- Neuromodulatory systems in the brainstem
- The cortical regions to which these neuromodulatory systems project
Neuromodulatory systems involved in alertness are sometimes referred to as…
Subcortical arousal systems
Name the three brainstem modulatory systems
- Upper brainstem (midbrain)
- Upper brainstem and reticular formation
- Basal forebrain
Neuromodulatory systems involve two aspects, what are they?
- Structure
- Neurotransmitter
There are a number of neuromodulatory systems in the brainstem, each system uses different ____________________, and is involved in alertness and cognitive processes
neurotransmitters
Each neuromodulatory system contributes to different cognitive processes, true or false?
True
All neuromodulatory systems act separately to allow for alertness, true or false?
False, the systems cooperate to allow for alertness
What activates a neuromodulatory system? (Which brain regions provide input to the parts of the upper brain stem/reticular formation mediating alertness?)
- Ascending sensory inputs (anterolateral pathway)
- Frontoparietal association and limbic cortices
- Hypothalamus
The following brain regions provide input to the upper brainstem and reticular formation for the mediation of alertness. What does each control?
- Ascending sensory inputs (anterolateral pathway)
- Frontoparietal association and limbic cortices
- Hypothalamus
- Ascending sensory inputs
- Pain can increase alertness - Frontoparietal association and limbic cortices
- Cognitive and emotional processes can modulate alertness - Hypothalamus
- Fight or flight
What happens when the brain regions that provide input to the upper brainstem and reticular formation for the mediation of alertness are damaged?
The individual will experience a lack of alertness/consciousness. This may present as coma, vegetative state, or minimally conscious state.
If someone is presenting with a _____________, psychologically meaningful or purposeful responses mediated by the cortex are absent.
Coma
An individual in a coma may show…
Reflexive eye movements (e.g., VOR), respiratory movements, and/or posturing
Explain decorticate posturing
A person’s arms are flexed, and their legs are extended, indicating damage to the cerebral hemispheres.
Explain decerebrate posturing
A person’s arms and legs are extended, suggesting damage to the brainstem.
Explain the characteristics of a vegetative state
There are no meaningful responses, speech or gestures, but the person may open eyes and arouse in response to stimulation, turn eyes and head toward auditory and tactile stimulation, and/or have unintelligible sounds
Explain the characteristics of a minimally conscious state
Can occur after the vegetative state OR as a primary state. Appearance of visual tracking may be one of the earliest signs, minimal or variable degree of responsiveness (simple commands, single words, reach/hold objects), not reliable for yes and no.
