States of Consciousness
PSYC 1301
Awareness is the monitoring of information from the environment and from our own thoughts. Consciousness is an awareness of our surroundings and thoughts, including aspects of being awake and aware. It is our awareness of various mental processes or cognitive processes that operate in our daily lives such as making decisions, daydreaming, reflecting, sleeping, dreaming and concentrating. It is our experience of the moment as we move through it; therefore, it is constantly changing. We process information before sending it to specialized brain regions. These sensory elements are brought together into what Baars (1997) called the global workspace of consciousness.
Wakefulness is the degree of alertness, resulting from whether a person is awake or asleep. Awareness, on the other hand, refers to the monitoring of information from the environment and from our own thoughts. Degrees of wakefulness and awareness signify variations in consciousness.
Minimal consciousness refers to states when people are barely awake or aware. Someone in a minimally conscious state is largely unresponsive but may show some deliberate movement.
Moderate consciousness describes occurrences when information is potentially accessible but not currently in awareness. For instance, a person can be aroused from sleep or dreaming but most sensations from the environment are not perceived by the sleeper. The tip-of-the-tongue phenomenon, when you feel you know something but just can't quite recall it, is an example of moderate consciousness.
When we are relatively alert and aware, we are said to be in full-consciousness. Mindfulness is a heightened awareness of the present moment. Flow, on the other hand, occurs when we get so involved in what we are doing that we lose a sense of time and place.
We call the limited capacity to process information that is under conscious control attention. Selective attention is the ability to focus on specific features in the environment while ignoring others. Individuals who suffer from schizophrenia lack the ability to selectively filter out and attend to only the most relevant information causing their mind to go into overload. For any of us, this selective attention creates gaps in attention and perception because we focus so much on certain things that we are blind to other things. We commonly say we "tune out" information that we consider irrelevant to us at the time.
Multitasking
Sustained attention is compromised when we multitask. While we may pride ourselves on our ability to multitask, research shows that concurrent or parallel tasking rarely occurs. We are actually fast switching our attention from one task to another. Switching loses time and compromises memory for the tasks at hand. Multitasking also compromises learning. To explain the limitations of multitasking, Salvucci and Taatgen (2008) proposed the threaded cognition theory. According to this theory, a particular resource such as motor skills can only be used one task at a time. When tasks compete for access to consciousness, a bottleneck can occur.
Studies show there are few super-taskers – we just like to think we fit into that category.
There is a situation in which we suddenly hear our name from across the room, and we say it catches our attention. This refocus of attention when you hear your name is known as the cocktail party effect.
Watch a video of two basketball teams, with one team dressed in white T-shirts and the other in black shirts. Watch the clip by clicking here. Did you see anything other than a team in white T-shirts and a team in black T-shirts?
Failure to notice unexpected objects/persons in our surroundings is referred to as inattentional blindness. The perceptual load model states that we do not notice potential distracters when a task consumes all of our attention capacity. Sustained attention describes the ability to maintain focused awareness on a particular target.
There has been a lot of discussion in recent years about cell phone use while driving. From media coverage, we all know the potential danger of cell phone use while driving. Recent research found that using a cell phone while driving, even with hands-free devices, is comparable to driving drunk. These drivers tend to follow other cars too closely, have more accidents than others, and slower braking reactions than others in the general population.
Functions of Sleep
Sleep supports neural growth, memory consolidation, and protection against cellular damage. Sleep researchers are finding that sleep is essential for learning and memory, and lack of sleep impacts health, safety, and longevity. Sleep deprivation inhibits the growth of new neurons, so pulling those all-nighters to write research papers is really having a detrimental effect. Sleep also helps us learn and remember things so staying up all night cramming for an exam can also be detrimental. Finally, sleep fights cell damage by triggering the production of enzymes that fight cell damage. Despite these findings, research shows that forty percent of American adults are sleep-deprived.
A biological cycle, or rhythm, that is approximately 24 hours long is called a circadian cycle. This biological clock is actually a cluster of neurons in the hypothalamus. Body temperature, the hormone melatonin, and alertness each fluctuate on a circadian cycle. Any disruptions in this wake-sleep cycle causes fatigue and irritability.
A phenomenon closely related to disruptions of this wake-sleep cycle is jet lag when the circadian cycle is thrown off its usual track.
An overview of the human biological clock.
The brain is active when we are asleep but it is only partially processing information from the outside world. While we are asleep, there is a "wall" between the outside world and the conscious mind; however, the "wall" can immediately come down. We filter out important information such as an alarm clock from less important information such as background music. Sleep has its own pattern of activity. When awake, beta waves, rapid but low-energy waves, register in the brain. When relaxed or drowsy, our brain switches to alpha waves which are slower and slightly higher energy waves.
The first major form of sleep is non-REM which has few eye movements that are slow rather than fast.
Rapid Eye Movements (REM) are quick movements of the eye that occur during sleep and researchers believe they mark phases of dreaming.
REM is called paradoxical sleep because, while brain activity resembles those recorded during waking consciousness, the sleeper appears to be deeply asleep and is incapable of moving because of paralysis of the body's voluntary muscles.
People deprived of REM sleep show a rebound effect when allowed to rest undisturbed, and they spend more than the average amount of time in REM sleep.
Research also indicates that both human and nonhuman subjects spend more time in REM sleep, after learning difficult material.
Each night adults experience 4 to 6 different cycles of non-REM and REM sleep, each lasting about 90 minutes. Click here for a video clip of sleep patterns.
There are four stages of non-REM sleep.
Stage I Sleep
Stage II Sleep
Stage III Sleep
Stage IV Sleep
About 20% of Americans suffer from sleep disorders. At any given time, about 50 million Americans suffer from chronic, long-term sleep disorders. Twenty million experience occasional sleep problems. Research has found a link between sleep and both asthma and stroke.
Sleepwalking
We don't always think of sleepwalking as a disorder. It is more common among children than adults. People generally cannot be easily awakened from sleepwalking. They usually do not remember the next morning. Because sleepwalking occurs during non-REM sleep, the sleepwalker is probably not acting out a dream.
Nightmares and Night Terrors
Nightmares and night terrors are more common in children than adults. A child who is very tired is more likely to experience a night terror. These terrors usually occur in non-REM sleep. Night terrors occur in fewer than ten percent of children. Neither nightmares nor night terrors are evidence of psychological problems.
Insomnia
Insomnia is a sleep disorder characterized by difficulty in falling asleep or remaining asleep throughout the night and affects as many as 35 million Americans. Most episodes of insomnia are temporary and stem from stressful events. Insomnia is sometimes the result of a larger psychological problem such as depression. Loneliness can also contribute to insomnia.
Sleep Apnea
Sleep apnea is a disorder characterized by difficulties in breathing while asleep and affects 20 to 22 million Americans. The difference between insomnia and apnea is that insomnia is characterized by sleeplessness while apnea is characterized by breathing difficulties. Apnea can leave the person feeling exhausted during the day. It has been associated with depression, sexual dysfunction, difficulty concentrating, and headaches in adults, and hyperactivity, conduct disorder, and aggressiveness among children and adolescents. If apnea is severe, it can double or triple a person's risk of having a stroke or dying.
Narcolepsy
Narcolepsy is characterized by unexpected periods of sleep during the day. The person may suddenly nod off or lose muscle tone following moments of emotional excitement. The individual may suddenly fall asleep without warning even during alert activities during the day. People with narcolepsy fall immediately into REM sleep. Narcolepsy is believed to be caused by a defect in the central nervous system.
Hypersomnia
When a person sleeps more than 10 hours a day for two weeks or more, he or she is said to have hypersomnia. Hypersomnia involves urges to nap throughout the day, often during meals or conversations, and can be caused by other sleep disorders, brain injury, or depression.
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Visual or auditory experiences during sleep are known as dreams. Every culture attributes some meaning to these dreams. Less vivid dreams occur during non-REM sleep. The brain is relatively insensitive to outside sensory input during this phase. The brain draws on internal images from memory during the sleep cycle. When a person is close to waking, he is more likely to dream about recent happenings. On the average, people dream several times a night for about 1 to 2 hours. A person can have an average of four to five dreams in a night.
The painting to the left is The Persistance of Memory by Salvador Dali. Many of his works are thought to be influenced by his dreams. |
Do Dreams Represent Unconscious Wish Fulfillment?
2009 marks the 110-year anniversary of Sigmund Freud's book, The Interpretation of Dreams. Freud viewed dreams as guides to the unconscious. Freud said, "I shall demonstrate that there is a psychological technique which makes it possible to interpret dreams, and that on the application of this technique, every dream will reveal itself as a psychological structure, full of significance." He believed the thoughts, feelings, and drives that threaten the waking mind are released as distorted and disguised images in our dreams. Thus, dreams operate on two levels: the manifest level, which can be consciously recalled after waking up, and the latent level or unconscious level where the true meaning of the dream exists.
The theory of why we dream that considers neuronal activation, stimulation, and state of wakefulness is known as the Activation-Input-Mode (AIM). The AIM theory is one of the more popular biological theories for dreaming. According to AIM, activation involves the amount of neural activation and ranges from low to high activation. The input level of consciousness is the extent to which stimulation is external or internal, and the mode consists of dimensions that range from wakeful to dreaming states.
Cognitive Theorists suggest that dreams are not different from everyday thinking. They point out that memory, problem solving, and speech also take place in dreams.
Other theories, not discussed in this textbook, include the following:
Proponents of the Reverse Learning Theory (Crick & Mitchinson, 1983) propose that dreaming is a way of flushing away unnecessary information accumulated over the day – a kind of mental housecleaning so that we do not go into overload.
The Dreams for Survival Theory purports that dreams permit information critical for daily survival to be reconsidered and reprocessed during sleep. According to this theory, dreams represent concerns about daily lives and illustrate our uncertainty, indecision, ideas, and desires.
According to the Activation Synthesis Theory, the brain produces random electrical energy during REM sleep possibly due to changes in production of certain neurotransmitters. This electrical energy randomly stimulates memories lodged in various portions of the brain. The brain then takes chaotic memories and weaves them into logical story lines.
Some researchers believe that dreams are simply the brain processing the most recent events in a person's life. However, the most honest answer was probably given by Dr. Robert Stickgold, professor of psychiatry at Harvard Medical School and Beth Israel Deaconess Medical Center and preeminent sleep researcher, who said, "we don't have a clue." According to Dr. Stickgold, "This is the brain that's saying I had a lot of activity today, and I should try to form connections." Dr. Stickgold, however, did answer many sleep-related questions for the PBS program NOVA. Click here for his Q&A – maybe you will find answers to some of your sleep-related questions here.
Drugs are chemical substances that, when taken alter the structure or functioning of the body in some way. Psychoactive drugs change the way in which chemicals allow neurons to communicate with each other. We discussed neurotransmitters in the previous chapter. Psychoactive drugs can cause these transmitters to increase in amount, be blocked at receptor sites, or not be reabsorbed. These drugs affect behavior, thoughts or perceptions. These drugs may be naturally occurring or clinically synthesized. Attitudes toward drugs and drug-taking behavior vary across cultures. Drug misuse occurs when prescription or non prescription drugs are used inappropriately resulting in some form of physical, mental, or social impairment. A person can become physically dependent when he or she needs the drug to maintain normal function and cope in daily life. Psychological dependence occurs when the person compulsively uses a substance to alleviate boredom, regulate mood, or to cope with everyday life. It can also occur when the person needs to engage in the drug culture associated with a particular drug and does not feel emotionally normal without doing so. This continued use and physical or psychological dependence is known as an addiction. Prolonged drug use can cause relatively persistent changes in a brain pathway that causes basic drives. These changes are a major source of addiction. Drug tolerance occurs when increasing amounts of a drug are needed for the same effect.
Depressants
Depressants slow down activity of the central nervous system. Depressants are one of the most dangerous classes of drugs because the potential for death from overdose is high.
The most widely used depressant is alcohol. Used worldwide, alcohol leads to health problems, death, lost work productivity, and excessive spending. Because it is a depressant, it can lead to death due to toxicity.
Sedatives are a category of depressant drugs that provide a sense of calmness and sleep. They can create a feeling of stupor similar to alcohol intoxication. Barbiturates are more frequently prescribed as anticonvulsants today. Tranquilizers are prescribed for anxiety and stress. The tranquilizer Rohypnol, or roofies, is odorless and tasteless. It produces sleep and amnesia in heavy doses. We often hear it referred to as the date rape drug because it is used to spike drinks of rape victims.
Opiods or Opiates (narcotics)
Narcotics is a general term referring to drugs derived from opium or chemicals similar to opium. Most opium is acquired from the dried juice of the opium poppy or manufactured as artificial drugs. Opiates generally refer to opium, morphine, codeine, thebaine, and heroin. Synthetic opiods produce the same opiate-like effects. Since these opiods are used for chronic pain, many people inadvertently develop an addiction. The human body produces its own morphine-like substance called endorphins that bind to opium receptors and the brain and act as natural painkillers. Many people develop an addiction to opiods while being treated for chronic pain.
Stimulants or Uppers
Stimulants do just what the name implies – they activate or stimulate the nervous system. They produce heightened feelings of awareness. Caffeine is the most widely used stimulant. Too much caffeine can make people jittery and anxious. Nicotine is the active drug in tobacco. Within eight seconds of inhalation, nicotine reaches the brain. Nicotine primarily creates a feeling of arousal, although some smokers report that smoking calms them down. Nicotine is extremely addictive. Nicotine withdrawal can be as severe as heroin withdrawal.
Cocaine, derived from the cocoa leaf, is an extremely dependence-producing stimulant. When snorted, it causes a rush of euphoria leading to a sense of invulnerability and power. Because the high is very short, people quickly abuse it trying to reach that high again. Cocaine in freebase form is called crack and is typically smoked, which produces a stronger effect, leading to a stronger addiction.
Amphetamines are synthetically produced compounds that operate by depleting a naturally occurring transmitter in the body. Amphetamines were once prescribed as diet pills and to counter depression or ADHD. New research is showing that amphetamines are considered too dangerous to be used for these purposes. Amphetamine users often get into a cycle of use followed by a crash into depression or paranoia. Short-term effects include insomnia, headaches, decreased libido, and difficulty concentrating. Long-term use can lead to depression, paranoia, loss of control over behavior, and in some cases, amphetamine psychosis, a condition marked by hallucinations.
Today, crystal methamphetamine, known as ice, is smoked by users and leads to a more rapid rush that in turn causes a more serious addiction.
Ecstasy (MDMA) is similar chemically to amphetamines. Ecstasy, both a stimulant and a mild hallucinogen, is often used at "rave" or dance parties. Ecstasy is sometimes called the "love drug" or "hug drug" because it produces feelings of euphoria, warmth, and connectedness to others. Repeated use of Ecstasy can cause increased depression, slower cognition, and greater impulsivity
Hallucinogens
Hallucinogens alter sensory perceptions causing distortions of reality ranging from mild to extreme.
Marijuana, produced from the blossoms and leaves of the Cannabis sativa plant, alters mood to create a sense of euphoria and change of perception. There is some controversy on whether marijuana is addictive; however, research has shown that with habitual use, people develop cravings.
Lysergic acid diethylamide-25 (LSD)
LSD is a liquid ingested on solid substances such as sugar cubes and used for "trips" that are characterized by altered states of consciousness.
In conclusion, many of the drugs discussed are illegal. The possible penalty for employment and social disclosure is great. They do not come with a safety guarantee as to composition or strength, nor do we know much about the interactive effects of some drugs.
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Hallucinogens
Hallucinogens later sensory perceptions causing distortions of reality ranging from mile to extreme.
Marijuana, produced from the blossoms and leaves of the Cannabis sativa plant, alters mood to create a sense of euphoria and change of perception. There is some controversy on whether marijuana is addictive; however, research has shown that with habitual use, people develop cravings.
Lyseric acid diethylaminde-25 (LSD)
LSD is a liquid ingested on solid substances such as sugar cubes and used for "trips" that are characterized by altered states of consciousness.
In conclusion, many of the drugs discussed are illegal. The possible penalty for employment and social disclosure are great. They do not come with a safety guarantee as to composition or strength, nor do we know much about the interactive effects of some drugs.
To return to the session, close out this window or tab.
