States of consciousness Flashcards
Consciousness
The subjective awareness of mental events. It monitors the self and environment and controls thoughts and behaviour.
Attention
The focus of conscious awareness on limited stimuli to heighten sensitivity and information processing.
Divided attention
Attend to two or more tasks or stimuli. Measured with dichotic listening.
Flow
State of consciousness where someone is fully immersed in a task. Decreased activation of amygdala and medial prefrontal cortex. Increased activation of inferior frontal gyrus and putamen.
Measuring consciousness
Can be measured with self-report questionnaires (mindful attention and awareness scale, conscious quotient inventory), brain imaging techniques (EEG and fMRI), and behavioral observation. Flow of consciousness studied with experience sampling (beeper studies).
Mind wandering
Attention strays from a task to irrelevant sensory information. A stable condition more common when bored, stressed or sleepy. Less common when immersed.
Dichotic listening
Presented different information in each ear. Focusing on one and repeating out loud is shadowing. Priming is when exposure to a stimulus affects the performance of a task involving related stimuli. Information ignored is still being processed to some degree.
Automatisation
Developed through practice, previous deliberate actions become automatic. Automatisation and divided attention decrease detection of peripheral stimuli.
Day dreaming
Normal flow of consciousness. Attention diverted from external stimuli to internal plans and fantasies.
Dorsolateral prefrontal cortex
Involved in working memory and conscious decision making. Activated when exercising conscious control, demonstrated with Stroop task.
Stroop task
Colours are written as words but in another colour. Participants are required to read the colours of the ink but ignore the words.
Anterior cirgulate cortex
Becomes active when consciousness regulates conflicting cues, such as Stroop task.
Selective attention
Process of filtering out irrelevant information.
Selective inattention
Process of ignoring relevant, but negative information. Can be adaptive or maladaptive.
Function of attention-orienting sensory stimuli
Turning sensory organs towards a stimulus (directing eyes). This activates parts of cortex to process stimulus and inhibits others. Watching a stimulus activates what and where visual pathways in the occipital, temporal and parietal lobes. Neural circuits activated in midbrain (superior colliculi controls eye movement), thalamus (directs attention to sensory systems), parietal lobes (direct attention to particular locations).
Control consciousness contents
Regulated by unconscious attentional mechanisms carried out by areas of frontal lobes and basal ganglia (thought, movement and self-control).
Maintaining alertness
Carried out by network of neurons from reticular formation (regulates states of awareness) through the frontal lobes.
Circadian rhythm
Biological cycle that evolved around daily cycles of light and dark. Circadian rhythm is drive to stay awake. Controls body temperature, hormones and other functions. Regulated by brains suprachiasmatic nuclei (SCN) located in the hypothalamus. Links to pineal gland that secretes melatonin. SCN is inactive at night. Free running circadian rhythm without zeitgebers (environmental cues) averages 24.2 hours. Homeostatic sleep drive works in balance. Sleep propensity is highest towards night and drops during sleep.
REM rapid eye movement sleep
Brain is very active like waking brain activity. Autonomic activity (pulse and blood pressure) increases. Most dreaming occurs. respiration becomes faster and irregular, sexual aroussal may occur. Muscle movement mostly inhibited. Occurs 4-5 times a night, increases from 5 minutes on first cycle.
Non REM sleep
Stages 1-4 of sleep. Stages are cycled every 90 minutes (shorter with age).
Awake
Irregular EEG brain activity. Beta waves of 14 cps. Eyes are closed and relaxed. Alpha waves of 8-12 cps emerge signaling transition to sleep.