Chap 22: Attention and Consciousness Flashcards
What is the difference between automatic vs conscious processes ?
- Automatic (bottom-up)
- automatic behaviors occurring without intention or awareness
- ex. stopping at a red light, red light triggers the body to stop - Conscious (top-down)
- selective focused attention
- ex. looking for a specific street sign, requires a desire to find a street, then selectively focusing on street signs as you’re driving
Describe the synchrony hypothesis of attention
attention system induces synchrony between neurons that assess the sensory signal
- the signal is around 40Hz
What is the competeition framework of attention ?
competition occurs since we cannot process everything at once, thus attention is a bias to resolve the competition
What brain areas are affected by the competition framework ?
- affects the anterior brain including the prefrontal cortex
What brain structures are involved in arousal ?
- the reticular activating system (RAS)
- the cholinergic and noradrenergic
- the thalamus
What is the role of the RAS in attention ?
- maintains alertness
- damage causes coma
What is the role of the thalamus in attention ?
- modulates alertness via the dorsomedial intralaminar and reticular nuclei (the RN inhibits the thalamus)
What is the role of the the cholinergic and noradrenergic systems in attention ?
- creates arousal
What is selective vs divided attention ?
selective: discriminating between relevant vs irrelevant stimuli (role of the pulvinar)
divided: allocating resources for multiple tasks at the same time
What brain structures are important for selective attention ?
- the pulvinar in the thalamus discriminates stimuli
- Pulvinar projects to the posterior parietal cortex, prefrontal cortex and temporal cortex
- Pulvinar receives input from midbrain colliculus
- Superior colliculus aligns visual attention to specific spatial location
What are the important components of the consciousness system ?
- anterior and posterior cingulate cortex
- medial frontal cortex
- frontal and parietal association cortex
What are the 4 prerequisites for consciousness ?
- Arousal
- Perception
- Attention
- Working memory
Describe the timeline of consciousness
prerequisites of consciousness contribute to whether or not an event reaches conscious awareness
- following the event post-perceptual processing occurs, and encoding into memory systems
Describe the arousal stage of consciousness
- arousal is necessary but not sufficient for consciousness
- attentional engagement is is needed at the time of the event for the stimulus to reach conscious awareness
- for a conscious event to be available later, it must reach the medial temporal memory circuit
Which brain regions are inactive when we are unconscious ?
Describe the coma state
- transient state where the eyes remain closed
- disturbances to normal sleep and wake cycle
- results from TBI lasting approx 10-14 days
Describe the minimally conscious state
- limited wakeful activity
- limited awareness of self and environment
- deep brain stimulation can brain patients back to life but it is not permanent
Describe locked-in syndrome
- NOT a disorder of consciousness
- a fully conscious state that appears as a coma or vegetative state
What is sensory memory ?
- the earliest step in information processing
- large capacity, very rapid, but short-lived
What are Posners 3 attentional networks ?
- Alerting
- Orienting
- Executive
Describe the alerting system
increases and maintains readiness for impending stimulus
- relies on norepinephrine
- tonic alertness (maintenance) belongs to the right hemisphere, parietal and frontal regions)
- phasic alertness (processing from event to event), relies on left hemisphere
Describe the orienting system
selecting specific information/stimuli either overtly or covertly
- relies cholinergic system
1. dorsal system ***
Describe the executive system
relates to task instructions prior to and during the task
- no universal agreement on definition
- relied on dopamine system
