Variations in Consciousness A.P. Psychology 12/18/2009

Drill ~ 12/18/2009 What is the major difference between the conscious, preconscious and unconscious mind?

Circadian Rhythm 24 hour biological cycles

Circadian Rhythms Especially influential for sleep, but also influence: –Blood pressure –Urine production –Hormonal secretions –Alertness –Short-term memory –Cognitive performance CR’s leave us primed to fall asleep most easily at a particular time of the day Example: –Body Temperature fluctuation Research shows that we tend to fall asleep as our body temperature begins to drop and awaken when it begins to rise again

Ignoring Circadian Rhythm’s If you ignore your biological clock –Quality of sleep suffers –Jet Lag ~ traveling across time zones Leads to fatigue, sluggishness, and irritibility Chronic Jet Lag leads to deficits in cognitive performance Readjustment? –Takes about a day for each time zone traveled through –Depends on the direction traveled as well (easier to fly westward than eastward) ~ has a significant impact on sports teams

Melatonin & Circadian Rhythm a hormone that seems to regulate the human biological clock Studies show that Melatonin can reduce the effects of jet lag Studies are inconsistent because timing of the dosage is key Melatonin may also be used as a mild sedative More effective when given in the daytime than at night It has also been hailed as a miracle drug for AIDS, Cancer, and sexual enhancement There is no research to support this

We spend about 8 hours per day, 56 hours perweek, 240 hours per month and 2,920 hours per year doing it...that's right...SLEEPING.

The Sleep & Waking Cycle Sleep is very misunderstood People think we do “nothing” while we sleep In reality, sleepers experience quite a bit of physical & mental activity throughout the night How do we know? Much research has been done in sleep laboratories, where volunteer subjects spend the night

Recording Devices Electroencephalograph Records brain waves –Beta (13-24 cps) »Normal waking thought –Alpha (8-12 cps) »Deep relaxation, blank mind and meditation –Theta (4-7cps) »Light sleep –Delta (less than 4 cps) »Deep sleep Electromyograph Records muscle activity and tension Electrooculograph Records eye movement Other devices monitor heart rate, breathing, pulse rate and body temperature

The Sleep Cycle Stages 1 – 4 Stage 1  brief transitional stage of light sleep and lasts about 1 – 7 minutes. Breathing & heart rate slow »Hypnic Jerks  brief muscular contractions that occur as people fall asleep Stages 2 – 4  respiration rate, heart rate, muscle tension, and body temperature continue to decline –Stage 2  10 – 25 minutes »Sleep Spindles  brief bursts of higher frequency brain waves –Stage 3 & 4  Slow Wave Sleep »High amplitude, low frequency delta waves become prominent

REM & NREM Sleep REM Sleep –Rapid eye movement Irregular breathing & pulse rate –Relatively deep sleep marked by eye movement, high- frequency, low- amplitude brain waves and vivid dreaming –Sometimes called “Paradoxical Sleep” NREM Sleep –Stages 1 – 4 where eye movement is absent –Relatively little dreaming takes place here –EEG activity is varied