Consciousness
Sleep Patterns & Theories
Biological rhythms and sleep
- circadian rhythm - the biological clock; regular bodily rhythms that occur on a 24hr cycle
- Alpha waves - the relatively slow brain waves of a relaxed, awake state
- Delta waves - the large, slow brain waves associated with deep sleep
- Suprachiasmatic nucleus - a pair of cell clusters in the hypothalamus that controls circadian rhythm; modify feelings of sleepiness
- Sleep - periodic natural loss of consciousness
NREM 1 - first 15 minutes when you fall asleep: breathing slows, brain wave activity becomes more irregular
NREM 2 - the next 20 minutes after NREM1: sleep deeper, the brain has bursts of wave activity
NREM 3 - the next 30 minutes after NREM 2: slow, constant delta-wave activity in your brain, hard to wake up from
REM sleep - a recurring sleep stage during which vivid dreams commonly occur
Why we sleep:
- protection
- recovery
- memory consolidation
- creativity
- growth
Psychoactive Drugs
Psychoactive Drug - any chemical substance that alters perceptions, moods, mental processes, emotions, etc
- not all are illegal: alcohol, caffeine, medications
Tolerance - continuous use of a psychoactive drug leads to neuroadaptation
Addiction - a compulsive craving for a drug despite harmful consequences
Withdrawal - experiencing physical symptoms from not using a drug
Classifications
- depressants - reduce neural activity and slow down body functions
- stimulants - excite neural activity and speed up body functions
- hallucinogens - drugs that distort perception and can create sensory experiences without sensory input
Amphetamines - a group of synthetic drugs (substituted phenethylamines) that stimulate the reticular formation in the brain and cause a release of stored norepinephrine
Methamphetamine increases the amount of dopamine in the brain, which is involved in movement, motivation, and reinforcement of rewarding behaviors
Nicotine - stimulant (acetylcholine agonist), elevated mood, increased physical arousal, highly addictive
Cocaine - causes a euphoric high that heightens the senses, increases energy and mental alertness, and boosts confidence, making them feel more âalive.â This is because cocaine stimulates the brain's pleasure receptors, dopamine, and serotonin
Ecstasy (MDMA) - a synthetic drug that acts as a stimulant and hallucinogen. It produces an energizing effect, distortions in time and perception
Hallucinogens - drugs that distort perception and can create sensory experiences without sensory inputÂ
LSD - a potent hallucinogenâthat is, a drug that can alter a person's perception of reality and vividly distort the senses
Marijuana/THC -the psychoactive substance that produces the âhighâ associated with smoking marijuana and can also lead to central nervous system depression
SSRIs - commonly prescribed to treat major depressive and anxiety disorders
Dreams
What are Dreams?
hallucinations
tend to be vivid and bizarre and negative
Content of dreams
- can be influenced by recent events
- often relate to commonly performed tasks
- can be culturally influenced
Parallel Processing - while part of our mind is dreaming another part is monitoring our environment
- REM rebound - the compensatory increase of the frequency, depth, and intensity of REM sleep following sleep deprivation or significant stressors
Dream theories:
- Wish Fulfillment - to fulfill our wishes from the subconscious; Freud
- To remember - there are certain types of memory consolidation that only can happen while asleepÂ
- Reverse learning - to forget; helps us to drop unnecessary brain connections
- Conditional activation - keep our brains working
- PIRT primitive instinct rehearsal - to practice fight or flight response
- to heal - dreaming helps us to make things less psychologically painful
- problem-solving - our brains work more creatively while asleep
- neural activation - to make sense of random neural activity
- cognitive development - top-down control of our dream content; reflects knowledge and understanding
Manifest content - remembered storyline of a dream
Latent content - underlying meaning of a dream