Chapter 6 The Aware Mind Elements of Consciousness The brain makes a commitment to a choice as much as 10 seconds before we become aware of the decision What Does It Mean to Be Conscious Conscious a state of awareness Self awareness the special understanding of the self as distinct from other stimuli Stream of consciousness William James seemingly unbroken flow of conscious awareness Consciousness Sigmund Freud aspects of the mind that could be retrieved voluntarily in contrast to the unconscious parts of the mind that remain hidden to voluntary searches for information The Evolution of Consciousness consciousness grows the more complex and intense the higher we rise in the animal kingdom william james The self awareness aspect of consciousness as exemplified in I statements might be the rarest of all among living things Consciousness as Variations in Alertness Varying states of awareness help repair bodies and conserve energy o Food requirements would be higher if we didn t sleep o Maximizes safety Sleeping during your worse seeing cycle Consciousness as an Awareness of Ongoing Sensations Choose responses rather than respond instinctively The flexibility of choosing increases an animal s chance of survival Consciousness as Self Awareness Understanding that you re alive is correlated with a heightened meaningfulness of death opportunity to look in a mirror in the mirror Rouge test a dot of rouge is placed on a child s forehead and the child is allowed an o Prior to 18 months children do not show indication that they see themselves o After that they will rub at the spot and turn their bodies to get a better look demonstrating self awareness Animals showing social self awareness o Dolphins have special whistles that they seem to use for individuals like names o Chimps and elephants show grief when someone dies Searching for Consciousness in the Brain Brain o Houses mind o Maintains homeostasis Mind o Houses consciousness o Manages unconscious functions such as long term memory Consciousness is the complex interactions between areas of the cerebral cortex and the thalamus o enable consciousness but do not produce content Lesions of thalamus result in profound unconsciousness typically associated with brain death Reticular formation of brainstem raise and lower thresholds of conscious awareness Blinding Problem how the brain forms a unified whole out of large quantities of information Sensory information combines with an individual s past experience to produce expectations for managing a current situation o Part of stream of consciousness o Frontal lobes provide space for integration o Explains consciousness in a developing child o As child gains more experience consciousness improves What happens to consciousness during wakefulness and sleep Sleep a normal state of consciousness characterized by reduced awareness of external stimuli Wakefulness a normal state of consciousness characterized by alertness and awareness of external stimuli Circadian rhythms a daily biological rhythm Circadian Rhythms Biological clock an internal mechanism that provides an approximate schedule for a wide variety of physical processes o Controlled by hypothalamus o Interact with external stimuli known as zeitgebers Light natural zeitgeber Eating patterns Totally blind people experience longer than normal circadian cycles due to their lack of exposure to natural light Modern Challenges for Circadian Rhythms Invention of artificial light has shaped our contemporary sleep waking patterns into something different Between 40 and 80 of graveyard shifters experience shift maladaption syndrome Jet lag o Make more errors and have more accidents o Fatigue irritability and sleepiness o Flight attendants have reduced reaction time and make 9 more mistakes on memory tasks Daylight savings When less light is available for setting the body s internal clocks 4 to 6 of pop will experience a type of depression Seasonal Affective Disorder SAD Seasonal Affective Disorder a mood disorder in which depression occurs regularly at the same time each year usually during the winter months o Treated by exposure to bright lights Artificial light affects sleep by breaking down melatonin o Changes in melatonin release have been implicated in a long list of human diseases like cancer and heart disease o Obesity and tobacco have a bad effect on melatonin Individual Variations in Circadian Rhythms Different circadian rhythm patterns may result from different versions of the genes responsible for the activity of our internal clocks Wakefulness Varying states of awareness can be described using electroencephalogram EEG recordings which provide a general measure of overall brain activity During wakefulness we alter between two patterns of activity o Beta wave a waveform recorded by EEG that usually indicates alert o Alpha wave a waveform recorded by EEG that usually indicates relaxed wakefulness Rapid irregular low amplitude waves 15 20 cycles per second wakefulness Slower larger and more regular 9 12 cycles per second Just have to close your eyes Daydreaming mind wandering spontaneous subjective experiences in a no task no stimulus no response situation Certain parts of the brain become more active during times when we are not faced with particular demands for our attention o Form a default network medial prefrontal cortex posterior cingulate cortex and cortex located at the junction of the temporal and marietal lobes When we work on a difficult task requiring our undivided attention we engage in executive network o Includes anterior cingulate corex and dorsolateral prefronal cortex Sleep 1 3 of our lives Stages of Sleep two types of sleep o Rapid Eye movement sleep REM the component of sleep characterized by waveforms resembling wakefulness as measured by EEG accompanied by rapid eye movements muscular paralysis and autonomic nervous system activation o Non rapid eye movement sleep N REM the components of sleep characterized by thetat and delta wave activity as recorded by EEG and deep physical relaxation Stage1 theta waves 4 7 cycles per second larger and slower than alpha waves Stage2 person is asleep reduction in heart rate and muscle tension shows K complexes and sleep spindles Stage3 Stage4 both show delta wave largest slowest 1 4 cycles per second very deeply asleep in these stages o First episode of REM sleep occurs between 90 and 120 min after onset of sleep Called paradoxal sleep During REM EEG shows activity similar to waking
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