Consciousness and Its Variations

Chapter IV Consciousness and its Variations Intro: 4. 1 Consciousness Your immediate awareness of thoughts, sensations, memories, and the world around you represent the experience of consciousness. William James described consciousness as a “stream” or “river. ” Although always changing, consciousness is perceived as unified and unbroken much like a stream. Because his idea of structuralism was based off of introspection, many of the leading psychologists at the turn of the twentieth century emphasized with the study of overt behavior, which could be directly observed, measured, and verified.

In mid 90’s many psychologists once again turned their attention to the study of consciousness. This was due to two main reasons. First it was becoming clear that a complete understanding of behavior would not be possible unless psychologists considered the role of conscious mental processes in behavior. Second was because psychologist had devised more objective ways to stud conscious experiences. For example, they could often infer the conscious experience that seemed to be occurring by carefully observing behavior.

Technological advances in studying brain activity were also producing intriguing correlations between brain activity and different states of consciousness. Different perspectives that psychologist are using to piece together a picture of consciousness are the role of psychological, physiological, social, and cultural influences. Biological and Environmental “clocks” that regulate Consciousness. Through the course of the day, there is a natural ebb and flow to consciousness. The most obvious variation of consciousness that we experience is the daily sleep-wake cycle. These daily cycles such as this are called circadian rhythms.

You actually experience many different circadian rhythms that ebb and flow over the course of any given 24hr period. Normally your circadian rhythms are closely synchronized with one another. For example, the circadian rhythm for the release of growth hormone is synchronized with the sleep-wake circadian rhythm so that growth hormone is released only during sleep. The suprachiasmatic Nucleus: Your main circadian rhythms are controlled by a master biological clock-a tiny cluster of neurons in the hypothalamus in the brain. This tiny cluster of neurons is called the suprachiasmatic nucleus, abbreviated SCN.

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The SCN is the internal pacemaker that governs the timing of circadian rhythms. The most important environmental time cue is bright light, especially sunlight. The light is detected by special photoreceptors in the eye and is communicated via the visual system to the SCN. As the sun sets each day, the decrease in available light is detected by the SCN, and then in turn the CN triggers an increase in the production of a hormone called melatonin. Melatonin is manufactured by the pineal gland, an endocrine gland located in the brain. Increased blood levels of melatonin help make you sleepy and reduce activity levels.

The levels of melatonin rise at night and peak around 0100 and 0300. Melatonin levels drop shortly before sunrises. The pineal gland stops producing melatonin, as the light from the sun is senesced by the SCN. Circadian Rhythms and Sunlight: The 24hr day Since the light from the sun helps regulate our circadian rhythm, what would happen if the external environmental factors were taken away? Well the circadian rhythm then will be referred to as a free-running condition, because the body’s internal clock runs freely and independently of external time cues.

Without the external time cues researchers have found that our internal body clock drifts to its natural (or intrinsic) rhythm. They also found that our natural circadian rhythm is about 24. 2 hours, or slightly longer than a day. Also as our melatonin peaks, our body core temperature also drops to it’s lowest. But when deprived of all external environmental cues your body’s sleep-wake, body temperature, and melatonin circadian rhythms become desynchronized. This means that they no longer properly coordinate with one another. An example is being jet lagged. Your out of sync with the sun set because the time zone difference is 12 hrs.

Sleep **Fun fact: over a person’s lifetime, you’ll spend approximately 22years of your life asleep. *** (Pg143) Prior to the 20th century, sleep was largely viewed as a period of restful inactivity in which dreams sometimes occurred. The Dawn of Modern Sleep Research The invention of the electroencephalograph by Hans Berger gave sleep researchers an important tool for measuring the rhythmic electrical activity of the brain. These electrical patterns were referred to as brain waves. The electroencephalograph produces a graphic record called EEG, or electroencephalogram.

By studying the EEG researchers firmly established that brain-wave activity systematically changes throughout sleep. Eye movements, muscle movements, breathing rates, airflow, pulse, blood pressure, amount of exhaled carbon dioxide, body temperature, and breathing sounds are just some of the body’s functions that are measured in contemporary sleep research. Nathaniel Kleitman used his 8-year-old son to discover a pattern from the EEG and his son’s rapid eye movements. More of these rapid eye movements were noticed when subjects reported dreams. Today we distinguish between two basic types of sleep.

REM sleep and NREM sleep. REM is often called active sleep or paradoxical sleep because it is associated with heightened body and brain activity during which dreaming consistently occurs. NREM sleep, or non-rapid eye movement sleep, is often referred to as quiet sleep because the body’s physiological functions and brain activity slow down during this period of slumber. NREM sleep is divided into four different stages. The onset of sleep and hypnagogic hallucinations Beta brain waves are produced as you prepare for bed. They are small, fast brain waves.

After you’re head hits the pillow and your body begins to relax, your brain’s electrical activity gradually gears down generating slightly larger and slower alpha brain waves. During this drowsy, pre-sleep phase, you may experience odd but vividly realistic sensations. You may hear your name called or a loud crash, fell as if you’re falling or floating, flying, or see kaleidoscopic patterns or an unfolding landscape. The most common hypnagogic hallucinations are the vivid sense of falling. This hallucination is often accompanied by a myoclonic jerk-an involuntary muscle spasm of the whole body that jolts the person completely awake.

The First 90 minutes of sleep and beyond Each NREM sleep stage is characterized by corresponding decreases in brain and body activity. On average the progression through the first four stages of NREM sleep occupies the first 50-70 minutes. STAGE 1 NREM As the alpha brain waves of drowsiness are replaced by even slower tbeta brain waves, you enter the first stage of sleep, which only lasts a few minutes. Stage1 is a transitional stage during which you gradually disengage from the sensation of the surrounding world. During stage 1 you can quickly regain conscious alertness if needed.

Although hypnagogic experiences can occur in stage one, less vivid mental imagery is common, such as imagining yourself engaged in some everyday activity. STAGE2 NREM Stage two represents the onset of true sleep. Stage two sleep is defined by the appearance of sleep spindles, brief bursts of brain activity that last a second or two, and K complexes, single high-voltage spikes of brain activity. Breathing becomes rhythmical, slight muscle twitches may occur, theta waves are predominant in stage two, but larger, slower brain waves, called delta brain waves, also begin to emerge.

During the 15-20 minutes initially spent in stage 2, delta brain-waves activity gradually increases. STAGE 3 NREM Stages three and four are physiologically very similar. Both are defined by the amount of delta brain-wave sleep. In combination they are sometimes reefed to as slow-wave sleep (SWS). When delta brain waves represent more than 20 percent of total brain activity, the sleeper is said to be in stage 3 NREM. When delta brain waves exceed 50% of total brain activity, the sleeper is said to be in stage 4 NREM. During the first 20-40 minutes of stage four NREM, delta waves eventually come to represent 100 percent of brain activity.

At that point, heart rate, blood pressure, and breathing rate drop to their lowest levels. In stage four the sleeper maybe totally oblivious to the world but his muscles are still capable of movement. For example, if sleepwalking occurs, it typically happens during stag 4 NREM sleep. In stage four NREM it is possible for a person to answer a ringing phone, carry on a conversation for severa minutes, and hang up without ever leaving stage 4 sleep- without remembering the conversation the next day. At this point the sleeper is approximately 70 minutes into a typical night’s sleep and immersed in deeply relaxed stage four sleep.

At this point the sequence reverses from stage 4 to 3 to 2 and then enters a dramatic new phase called REM. REM Sleep During REM sleep the brain becomes more active and generates smaller and faster brain waves. Visual and motor neurons in the brain activate repeatedly, just as they do during wakefulness. Dreams usually occur during REM sleep. Although the brain is very active, voluntary muscle activity is suppressed, which prevents the dreaming sleeper from acting out those dreams. REM sleep is accompanied by considerable physiological arousal. The sleeper’s eyes dart back and forth behind closed eyelids-the rapid eye movements.

Heart rate, blood pressure, and respirations can fluctuate up and down, sometimes extremely. Muscle twitches occur. In both sexes sexual arousal may occur. The first episode of REM sleep is about 5-15 minutes. From the first stage of NREM to the completion of the first cycle of REM usually lasts about 90 minutes has elapsed all together. Beyond the first 90 minutes Throughout the rest of the night, the sleeper cycles between NREM and REM sleep. Each sleep cycle lasts about 90 minutes on average, but the duration of cycles may vary from 70-120 minutes. Just and after REM sleep the sleeper changes positions.

Stage 3 and 4 NREM usually occur only during the first two 90-minute cycles. As the night progresses, REM sleep episodes become increasingly longer and less time is spent in NREM. During the last two 90-minute sleep cycles before awakening, NREM sleep is composed primarily of stage two sleep and periods of REM sleep can last as long as 40 minutes. Changing sleep patterns over a lifetime During the last trimester of prenatal development, active REM and quiet NREM sleep cycles emerge. In the final weeks, REM and NREM sleep are clearly distinguishable in the fetus.

Newborns sleep about 16 hours a day, although not all at once. Up to 8 hours or 50% of the newborn’s sleep is spent in REM sleep. The rest is spent in a quiet sleep that is very similar to NREM stages 1&2. Not until about the third month of life that the deep, slow-wave sleep of NREM stages 3&4 appear. Typically the 90-minute sleep cycle develops over the first few years of life. The infants first couple months is characterized as being a 60 minute sleep cycle, producing 13 sleep cycles per day. By the age of two the toddler is experiencing 75 minute sleep cycles.

By 5 years old the typical 90 minute sleep cycles of alternating NREM and REM sleep is established. Total time spent in slow-wave sleep (SWS) and sleep time decrease over the lifespan. Do we need sleep? Sleep deprivation studies has show us that after one nights sleep deprivation, subjects develop microsleeps, which are episodes of sleep lasting only a few seconds that occur during wakefulness. People who go without sleep for a day or more experience disruptions in mood, mental abilities, reaction time, perceptual skills, and complex motor skills.

People us to thing that a person can adapt to only having 4-5 hours of sleep, but this is simply not true. Sleep deprivation can decrease concentration, vigilance, reaction time, memory skills, and the ability to gauge risks. Why do we sleep? Toblers theory of restorative theory of sleep states that NREM is vital to restore the body while REM is used to restore the brain and mental functions. Dreams and Mental Activity during sleep4. 2 By the adulthood the average person spends 2hours a night dreaming. So if you live to a ripe old age. You will have spent about six years of your life dreaming.

Although dream may be the most spectacular brain production during sleep, they are not the most common. More prevalent is sleep thinking, also called sleep mentation. Sleep thinking usually occurs during NREM slow-wave sleep. Sleep thinking probably contributes to those times when you wake up with a solution to some vexing problem. When awakened during active REM sleep, people report a dream about 95% of the time. Early morning dreams are the longest lasting up to 40 minutes and are the most likely to be remembered by the dreamer. People usually have four or five dreams a night. Sleep and memory consolidation: let me sleep on it.

Research shows that different sleep states and stages contribute to forming different kinds of memories. Evidence suggests that NREM sleep contributes to forming new episodic memories, which are memories of personally experienced events. In contrast, REM sleep and NREM stage2 sleep seem to help consolidate new procedural memories, which involve learning a new skill or task until it can be performed automatically. So how does sleep strengthen new memories? Almost a century ago John Jenkins and Karl Dallenbach showed that memories could be enhanced by sleep as compared to an equal amount of time spent awake.

Their explanation was that, compared to wakefulness, sleep kept additional information from interfering with new memories. This explanation was however wrong. The correct answer using today’s new technology is that: New memories formed during the day are reactivated during the 90-minute cycles of sleep. This process of repeatedly reactivation these newly encoded memories during sleep strengthen the neuronal connections that contribute to forming long-term memories. So after forming new memories or learning something it is best to sleep after wards. It is also important to sleep prior to learning.

This has been proven to increase the chances of retaining information. Dream Themes and Imagery: Here are some patterns and themes that are well-substantiated findings on dream content. 1) Women report males and female in equal proportion as other dream story characters. 2) Men are more likely to repot other males as the dream story characters. 3) Negative feelings and events are more common than positive ones. 4) Instances of aggression are more common than are instances of friendliness. 5) Dreamers are more likely to be victims of aggression than aggressors in their dreams. ) Men are more likely than women to report dreams involving physical aggression. 7) Women are more likely than men to report emotions in their dreams. 8) Sex and sexual behaviors seldom occur as elements of the dream. 9) Apprehension or fear is the most frequently reported dream emotion for both sexes, followed by happiness and confusion. If apprehensive or fearful emotions become progressively more intense as a dream story unfolds, there person may experience a nightmare. The nightmare typically has the dreamer as being helpless or powerless in the face of being aggressively attacked or pursued.

Although fear, anxiety, and even terror are the most commonly experienced emotions, some nightmares involve intense feelings of sadness, anger, disgust, or embarrassment. The Significance of Dreams Sigmund Freud “Dreams as fulfilled wishes” He was the founder of psychoanalysis. Freud believed that sexual and aggressive instincts are the motivating forces that dictate human behavior. Because these instinctual urges are so consciously unacceptable, sexual and aggressive thoughts, feelings, and wishes are pushed into the unconscious, or repressed. However, Freud believed that these repressed urges and wishes ould surface in dream imagery. Freud believed that dreams had two components. The manifest content, and the latent content. The manifest content being the dream itself and the latent content being the disguised psychological meaning of the dream. The Active-Synthesis Model of Dreaming Founded by J. Allan Hobson and Robert McCarley and stated that dreaming is our subjective awareness of the brain’s internally generated signals during sleep. That the experience of dreaming sleep is due to the automatic activation of brainstem circuits at the base to the brain.

So the brainstem sends electrical messages to the brain and then the brain attempts to make sense of the messages. Sleep Disorders 4. 2 According to data from National Sleep Foundation’s annual polls, 7 out of 10 people experience sleep disruptions. People with trouble sleeping usually complain about one or more of the following: Insomnia, Excessive daytime sleepiness, and Abnormal behaviors or sensations during sleep. Sleep disruptions become a sleep disorder when A) abnormal sleep patterns consistently occur, B) They cause the subject distress, and C) they interfere with a persons daytime functioning.

All sleep disorders can be classified into two broad categories. First is the dyssomnias, which are sleep disorders involving disruptions in the amount, quality, or timing of sleep (insomnia, obstructive sleep apnea, and narcolepsy). Then there is the parasomnias, which are sleep disorders involving undesirable physical arousal, behaviors, or events during sleep transitions. People are said to have insomnias when they repeatedly complain about quality or duration of their sleep, have difficulty going to sleep or staying asleep, or wake before it is time to get up. Transient insomnias last anywhere from about 1-2 nights to a couple weeks.

Chronic insomnias last at least three nights each week that persist for a month or longer. Women are more predisposed to insomnias than men. Insomnias are also influenced by age, and gender. Most commonly insomnias can be traced to anxiety over stressful life events. Obstructive sleep apnea Sleep apnea is the second most common type of sleep disorder characterized by daytime sleepiness and excess snoring. The sleeper’s airway becomes narrowed or blocked, causing very shallow breathing or repeated pauses or stops breathing. Each time breathing stops, oxygen blood levels decrease and carbon dioxide blood levels increase.

Sleep apnea tends to run in families and is more predominate in middle age males. To treat sleep apnea requires a life style change. Usually its treaded by loosing weight, avoiding alcohol, surgery to widen breathing passages, or a special mouth piece. Sever to moderate sleep apnea is treated with positive airway pressure from a CPAP. Narcolepsy People with narcolepsy experience or abundance of daytime fatigue regardless of the amount of time asleep. This uncontrollable event of a rapid onset of sleepiness is called sleep attacks or microsleeps. About 70% of people who suffer from narcolepsy experience cataplexy.

Cataplexy is the sudden loss of voluntary muscle strength and control, lasting from several seconds to several minutes. People with narcolepsy also can experience sleep paralysis. Parasomnias In a parasomnias, the person’s brain is just awake enough to carryout the actions yet is still immersed in sleep that he or she has no conscious awareness or subsequent memory of having performed the action. Parasomnias occur during NREM stages 3 & 4, are more common in children and decrease with age, occurs in multiple family member, suggest a genetic predisposition. Sleep Terrors:

Also called night terrors, typically occur in the first few hours of sleep during stage 3 & 4 NREM. Physiologically, the first sign of a sleep terror is sharply increased physiological arousal, restlessness, sweating, and a racing heart rate. The difference between a sleep terror and a nightmare is as follows: Whereas nightmares involve a progressive unpleasant dream story, a sleep terror is usually accompanied by a single but terrifying sensation, such as being crushed or falling. Sleepsex Also called sexsomnia, involves abnormal sexual behaviors and experiences during sleep.

Without realizing what he or she is doing, the sleeper initiates dome kind of sexual behavior, such as masturbation, sleepsex-talking, groping or fondling their bed partner’s genitals, or sexual intercourse. Sleepwalking Also called somnambulism. Sleep-Related Eating Disorders Frequent sleepwalking episodes to the kitchen, compulsive eating, and then awakening the next morning with no memory of having done so are the hallmarks of sleep-related eating disorders. The dangerous part of this is when the subject eats non-food items such as cat food, raw bacon, salt sandwiches, coffee grounds, or hand creams. Hypnosis 4. 3

Hypnosis can be defined as a cooperative social interaction in which the hypnotic participant responds to suggestions made by the hypnotist. Hypnosis is characterized by highly focused attention, increased responsiveness to suggestions, vivid images and fantasies, and a willingness to accept distortions of logic or reality. Effects of Hypnosis Subjects of hypnosis may report detachment from their bodies, profound relaxation, or sensations of timelessness. Sensory and perceptual changes Sensory changes that can be induced through hypnosis include temporary blindness, deafness, or a complete loss of sensation in some part of he body.

People can also experience hallucinations under hypnosis. Hypnosis can also influence behavior outside the hypnotic state. When a posthypnotic suggestion is given. The person will carry out that specific suggestion after the hypnotic session is over. Hypnosis and memory Memory can be effected by posthypnotic amnesia, in which a subject is unable to recall specific information or events that occurred before or during hypnosis. The opposite effect is called hypermnesia, which is enhancement of memory for past events through hypnotic suggestions. Explaining Hypnosis

Psychologist Ernest R Hilgard believed that the hypnotize person experiences dissociation- the splitting of consciousness into two or more simultaneous streams of mental activity. This is called Hilgard’s neodissociation theory of hypnosis. Limits and applications of Hypnosis Contrary to popular belief, you cannot be hypnotized against your will. Second hypnosis cannot make you perform behaviors that are contrary to your moral and values. Third, hypnosis cannot make you stronger than your physical capabilities or bestow new talents. Hypnosis can be used to help modify problematic behaviors.

Meditation Meditation refers to a group of techniques that induce an altered state fo focused attention and heightened awareness. Common to all forms of meditation is the goal of controlling or retaining attention. There are two general categories of meditation, Concentration techniques involving focusing awareness on visual image, your breathing, a word, or a phrase. When a sound is used, it is typically a short word or religious phrase, called a mantra. The second category is opening-up techniques involving a present-centered awareness of the passing moment, without mental judgment.

Rather than concentrating on an object, sound, or activity, the meditator engages in quiet awareness of the “here and now” without distracting thoughts. Effects of meditation The early research on meditation focused on its use as a relaxation technique that relieved stress and improved cardiovascular health. Numerous studies now show that practicing TM (transcendental meditation) subjects experience a state of lowered physiological arousal, including a decrease in heart rate, lowered blood pressure, and changes in brain waves. Psychoactive Drugs 4. 4

Psychoactive drugs are chemical substances that can alter arousal, mood, thinking, sensations, and perceptions. There are four categories of psychoactive drugs and they are depressants (drugs that depress, or inhibit, brain activity), opiates (drugs that are chemically similar to morphine and that relieve pain and produce euphoria), stimulants (drugs that stimulate, or excite, brain activity), and psychedelic drugs (drugs that distort sensory perceptions). The Depressants Alcohol, Barbiturates, Inhalants, and Tranquilizers The depressants are a class of drugs that depress or inhibit central nervous system activity.

In general, depressants produce drowsiness, sedation, or sleep. Alcohol Used in small amount alcohol reduces tension and anxiety, along with reducing the risk of heart disease. Alcohol can also be misused and considered a dangerous drug. How does alcohol affect the body? Generally it takes about one hour to metabolize the alcohol in one drink, which is defined as 1 ounce of 80 proof whiskeys, 4 ounces of wine, or 12 ounces of beer. Alcohol depresses the activity of neurons throughout the brain. As the blood alcohol levels rise, the more brain activity that is impaired.

Because alcohol is physically addictive, the person with alcoholism who stops drining may suffer from physical withdrawal symptoms. Inhalants Inhalants are chemical substances that are inhaled to produce an alteration in consciousness. At low doses, they may cause relaxation, giddiness, and reduced inhibition. At higher doses inhalants can lead to hallucinations and a loss of consciousness. Repeatedly inhaling is a practice that increases risk of serious damage to the brain, heart, and other organs. In a study using a inhalant abuser and a cocaine addict that tested both subjects cognitive abilities.

The cocaine addict actually scored higher than the inhalant abuser. Even though they both were below the norm for non-users. Barbiturates-Tranquilizers Barbiturates are powerful depressant drugs that reduce anxiety and promote sleep, which is why they are sometime called “downers. ” Barbiturates depress activity in the brain center that control arousal, wakefulness, alertness, and also depress the brains respiratory centers. Low doses cause relaxation, mild euphoria, and reduced inhibitions, but larger doses produce a loss of coordination, impaired mental functioning, and depression.

High doses can produce unconsciousness, coma, and death. Barbituates produce a very deep but abnormal sleep in which REM sleep is greatly reduced. Tranquilizers are depressants that relieve anxiety. Common prescribe tranquilizers are Xanax, Valium, and Ativan. The Opiates Often called narcotics, these groups of addictive drugs relieve pain and produce feelings of euphoria (a feeling of happiness, confidence, or well-being some times exaggerated in pathological states as mania). Opiates produce their powerful effects by mimicking the brain’s own natural painkillers, called endorphins.

Heroin, OxyContin, Demorol, Fentanyl, Percodan, and Vicodin. The Stimulants Caffeine, Nicotine, Amphetamines, and Cocaine Stimulants vary in the strength of their effects, legal status, and the manner in which they are taken. All stimulants however are at least mildly addicting, and all tend to increase brain activity. Caffeine and Nicotine Caffeine is the most widely used psychoactive drug in the world. Its found in almost everything (soda, coffee, tea, chocolate, and cola drinks). Caffeine stimulates the cerebral cortex in the brain, resulting in an increase in mental alertness and wakefulness.

Nicotine, contrary to popular belief does not relax the body. Instead it stimulates it. Nicotine increases neural activity in many area of the rain, including the frontal lobes, thalamus, hippocampus, and amygdala. Amphetamines and Cocaine Like caffeine and nicotine, amphetamines and cocaine are addictive substances that stimulate brain activity, increasing mental alertness and reducing fatigue. Amphetamines is sometimes called “speed” or “uppers. ” Amphetamines suppress appetite and were once widely prescribed as diet pills. Cocaine is an illegal stimulant derived from the leaves of the coca tree.

Inhaling cocaine produces intense euphoria, mental alertness and self-confidence. A more concentrated form of cocaine is called “crack” which is smoked instead of inhaled. Prolonged use of cocaine and amphetamines can result in stimulant-induced psychosis, which have Schizophrenia-like symptoms, including hallucinations of voices and bizarrely paranoid ideas. Psychedelic Drugs Mescaline, LSD, and Marijuana This is a group of drugs that create profound perceptual distortions, alter mood, and affect thinking. Psychedelic literally means “mind manifesting. ” Mescaline and LSD Mescaline was derived from the peyote cactus.

Another psychedelic drug is psilocybin which is derived from the Psilocybin mushroom or sometimes called the “magic mushrooms” or “shrooms. ” Mescaline and LSD are very similar chemically to the neurotransmitter serotonin, which is involved in regulating moods and sensations. These drugs can sometime have a “bad trip” were the user doesn’t get the results the wished for but they get the opposite. Marijuana The common hemp plant, Cannabis sativa, is used to make rope and cloth. But when its leaves, stems, flowers, and seeds are dried and crushed, the mixture is called marijuana. Designer “Club” Drugs Ecstasy and dissociative anesthetic drugs

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