Chapter 5 Body Rhythms and Mental States

Chapter 5 – Body Rhythms and Mental States

Consciousness is an awareness of self and environment. This change in mood, alertness, efficiency ebbs and flow throughout the day.

Examining the on going rhythmic cycles is like watching a motion picture of consciousness; studying the person’s distinct states of consciousness is like viewing each frame separately.

The chapter examines: 1) The Movie – how consciousness and functioning varies periodically over time - rhythmically. 2) A Frame in time (a state of consciousness) in the world of dreams 3) Re-touching the film (the influence of recreational drugs and hypnosis on consciousness)

We all experience dozens of periodic, fairly regular ups (waxing) and downs (waning) in physiological functioning. A biological clock in the brain (a tear drop like shaped cluster of cells in the hypothalamus called the SCN supra-chi-as- matic nucleus) for example governs the waxing and waning of: hormone levels, urine volume, blood pressure and even responsiveness of brain cells to stimulation.

*Supra means transcending above. Chiasma is a crossing or intersecting of two (nerve or ligament) tracts.

Biological Rhythm A periodic somewhat regular fluctuation in a biological system, it may or may note have psychological implications.

Internal (endogenous) biological rhythms are usually synchronized with external (exogenous) events such as changes from day to night (circadian rhythm), seasonal changes in the calendar (infradian rhythms) and clock changes from minute to hours throughout the day (ultradian rhythms). This internal-external synchronization is called entrainment (to pull or carry along after one’s self).

The three categories of biological rhythms

1) Circadian rhythm – a biological rhythm of about 24 hours with a period from peak to trough of about 24 hours. Example – the sleep-wake cycle among hundreds of others. Body temperature fluctuates one degree centigrade each day rising (peaking) in later afternoon and hitting a low point in the wee hours in the morning.

2) Infradian rhythms occur less often than once a day, more at once a month or twice a season. Example, the human female menstrual cycle which occurs every 28 days; birds migrate south for the winter and bears hibernate.

3) Ultradian rhythms occur more often than once a day, frequently on or about a 90-minute cycle. Other examples include stomach contractions, hormone levels, susceptibility to visual illusions, verbal/spatial performance brain wave responses during cognitive tasks alertness and daydreaming.

Why Study Biological Rhythms? They affect everything, eg., the effectiveness of medication taken at different times of the day to alertness and performance on the job.

1) Circadian rhythms occur in all life forms and is impacted by changes in light, air pressure temperature associated with the earth’s rotation on its axis.

Our bodies adapt to a 24 hour cycle bodily rhythms become entrained by external cues. Studying endogenous rhythms requires isolation from external cues (eg., clocks and other markers of night and day).

Subjects studied in controlled environments (underground caves, salt mines) isolating them from external cues with one-way communication to the surface reveal the following:

Bodily norm reverts to a 24.3 hour cycle, when put on a 28 hour day cycle, body temperature and hormone levels follow a 24.18 hour cycle (Czeisler et al., 1999). The Body’s Clock The suprachiasmatic nucleus SCN controls the body’s rhythms. Neural pathways in the back of the eyes feed signals back to the SCN allowing it to respond to light and dark. It then sends out messages to the brain allowing it to adapt to these changes.

Melatonin The SCN regulates fluctuating levels of hormones and neurotransmitters, they in turn provide feedback that affect the SCN’s functioning. During dark hours the SCN regulates melatonin, a hormone secreted by the pineal gland deep within the brain. Darkness decreases the level of melatonin, brightness increases it. Melatonin appears to help the biological clock keep phase with light-dark cycles (Haimov & Lavie, 1996; Lewy et al., 1992). Melatonin promotes sleep, it is often absent in blind people.

The rhythms governed by the suprachiasmatic nucleus are synchronized with one another but may peak at different phases, the peaking of one predicts the peaking of another. When the normal rhythms are thrown out of sync the resulting internal de-synchronization compromises performance. Examples are the Exxon Valdez oil spill.

Shift workers would fare better were they allowed to establish a stable routine.

2) Infradian Rhythms Long Term Impact on Mood and other Cycles Season Affective Disorder (SAD)is common during the winter months are may be the result of decrease sun light (Rosenthal, 1998). Evidence for SAD comes form clinical case studies, extrapolations from patient cases. Surveys places the prevalence of SAD as low as .4% and .01% for major/minor SAD (Blazer, Kessler & Swartz, 1998). There is some evidence that photo (light) therapy may be an effective for SAD and some speculation that such patients may have low levels of melatonin (Lewy et al., 1998).

Is SAD the result of realizing yet another birthday? Holiday blues? Decreased physical activities in the winter?

The Menstrual Cycle occurs on average every 28 days. During the first half of the cycle there is an increase in estrogen and a thickening of the uterine lining in preparation for possible pregnancy. At mid cycle the ovaries release a mature egg (an ovum). The ovum sac which contained the egg begins to produce progesterone which helps the uterine lining to receive the egg. If pregnancy does not occur estrogen and progesterone levels fall and the uterine sloughs off as the menstrual flow and the cycle begins again.

Symptoms associated with menstruation (observed cross culturally) includes: tenderness of the breasts, water retention and abdominal cramps. Pre-menstrual syndrome, a term popularized during the 1970's to include symptoms such as: irritability, fatigue, headache and depression appears uniquely a western concept (Parlee, 1994). Less than 5% of women have such symptoms predictable over the course of their cycle (Brooks-Gunn, 1986; Reid, 1991). Menstruation is cyclic but not for women beyond menopause.

Do women conform to behavior expected of someone who is pre-menstrual? Would eliminating the definition eliminate psychological reality of the syndrome?

3 Ultradian rhythms occur more often than once a day, frequently on or about a 90-minute cycle. The diurnal sleep cycle is an example of ultradina rhythm in motion.

Question: What is the evolutionary adaptive function of sleep? Answer: The function of sleep is…

Sleep Research In 1955 a sleep researcher named Nathaniel Kleitman asked one of his graduate students to monitor the EEG of one of his sleeping laboratory subjects, the graduate student William Dement noticed discernable brain wave activities which he reported. Another graduate student Eugene Aserinsky was asked to observe, his observation concurred with his colleague's. Thus was born the scientific study of sleep!

Sleep can be divided into four distinct stages

For a brief overview of the stages click here or for an expanded view click here.

Stage 1: light sleep, alpha waves - edge consciousness drifting off Stage 2: deeper sleep than stage 1, still fast waves. 45% of sleep Stage 3: deep, delta waves Stage 4: deeper sleep night terrors sleep walking

Stage 5: REM... dreams, muscle paralysis nightmares It takes between 30 - 40 minutes to reach stage 4, the stages then re-occur but in reverse order 3, 2, then 1, stage 1 then become the Rapid Eye Movement stage some 70 - 90 minutes later.

REM sleep is embarked upon some 40 - 70 minutes after the end of stage 4. REM can be termed stage five sleep. Stage 5 is characterized by long bursts of very rapid somewhat irregular spikes in brain wave patterns. The eyes move rapidly as if tracking objects in motion. There is increased respiration and blood pressure, likewise penile and clitoral erection occurs, there is also vaginal lubrication. Paradoxically, the skeletal muscles become limp disallowing physical movement, in fact, this is termed paradoxical sleep. The first cycle of REM lasts between 5 - 20 minutes then gets progressively longer as the night wears on. There is an 82% likelihood of dreaming at this stage and dreams are reported as lucid Foulkes, 1962 reported 51% probability of dreams occurring during non-REM cycles.

The evolutionary adaptive function of REM sleep remains a mystery though several competing explanations are posited:

1) Unconscious Wishes - Psychoanalytic Theory (Freud ). Latent wishes, desires, impulses and other forbidden thoughts are expressed (manifested) symbolically during dreams. The thoughts are disguised as non-threatening symbols for us to interpret but not take literally. Flaws: The theory is farfetched and does not provide a reliable way to interpret latent content accurately.

2) Problem Focus (Siegel, 1991; Webb & Cartwright, 1978). Dreams serve to resolve ongoing conflicts and concerns of waking life. For example, if going through a divorce, dreams are more likely to contain marital related contents than would be predicted by chance occurrence (Cartright et al., 1998). Flaws: Doubt that people are able to workout their conflicts while sound asleep, dreams are merely an expression of the problem, insight may result only after people have had the change to figure out what was troubling them (Blagrove, 1996; Domhoff, 1998).

3) By-Product of Mental Housekeeping (Evans, 1984; Crick & Mitchison, 1995). The brain prioritizes weeding out the sensible form the non-sensible, strengthening neural connections between meaningful data while weakening connections in the case of meaningless data. Similar processes may occur in the strengthening of synaptic connections associated with recently stored memories - consolidating these connections. Flaws: The information processing theories do not explain why some dreams reoccur throughout the years, why some dreams are story-like in presentation. It may tell use more about REM than about dreams.

4) Activation-Synthesis Theory (Allan Hobson, 1988, 1990). Lower brain regions such as the pons emit random signals which are interpreted and synthesized by the cortex. The cortex imposes structure on the random firings. Flaws: Our interpretation of these random firing (the sense we make out of them) may be more a reflection of our concerns and conflicts. This theory however, does not explain the story-like quality of REM and N-REM dreams. Altered States of Consciousness

We began by using the movie analogy in describing consciousness, this is what we have covered thus far through our journey into consciousness:

1) The Movie – how consciousness and functioning varies periodically over time - rhythmically.

2) A Frame in time (a state of consciousness) in the world of dreams

Now briefly, we shall attempt to re-touch the film by taking a closer look at recreational drugs and hypnosis on consciousness. For a more in depth look at the topic click the link above or visit Dr. Charles T. Tart's archive, he has written extensively on states of consciousness.

3) Re-touching the film (the influence of recreational drugs and hypnosis on consciousness).

Throughout history humans have attempted in one way or another to alter consciousness, we will quickly look at four major classes of drugs and mention two others not yet officially classed.

A psychoactive drug is a substance that alters perception, emotion, mood, memory and the body's biochemistry. The four major categories are:

Stimulants Speeds up activities in the Central Nervous System to produce feelings of excitement, confidence well-being or euphoria. Increasingly large doses causes jittering, anxiety, hyper-alertness, convulsion, heart failure and death

Amphetamines -(met-amphetamines) are usually synthetic drugs in pill form. Cocaine naturally occurs in the leaf of the coca plant, in refine form it can be injected, snorted or smoked, the effects are more immediate and intense, the stimulants do not actually increase energy reserve, more the case that it depletes it. After effects are fatigue, depression and irritability. Nicotine is a stimulant thought its effect is calming and promotes alertness, it decreases an appetite for carbohydrates. Coffee and teas contain caffeine which is a stimulant.

Depressants Slows down the Central Nervous System to reduce guilt, anxiety, and tension. Increasing amounts causes irregular heartbeat, convulsion, inhibited breathing, and death.

Alcohol initially suppresses parts of the brain that inhibits impulses so one feels relaxed, euphoric, but then the anesthetic effect begins with increasing consumption. While alcohol consumption does not cause violent behavior, one is more likely to express impulsiveness and relinquish responsibility. Impaired coordination and cirrhosis and permanent neurological impairments may result from chronic use or abuse. Barbiturates - Phenobarbital; tranquilizers, valium and methaqualone are other depressants/sedatives, addictive.

Opiates Opiates are pain numbing, anxiety reducing and euphoric inducing substances which also decreases motivation. May result in convulsion, coma and death. Opium derives from the opium poppy, morphine from opium, heroin from morphine. Methadone is a synthetic drug. These drugs generally mimic endorphins and have powerful effects on emotions.

Psychedelics Disrupts normal perception of time, space and thought processes, produces visual hallucinations. LSD (lysergic acid diethylamine) is a synthetic drug. Mescaline form the peyote cactus and psilocybin (from certain species of mushrooms) are psychedelics. "Trips" may be very un/pleasant mystical or nightmares.

Sub-classifications are Anabolic Steroids Synthetic testosterone (pill or injection) increases muscle, may shrink the testes (normal production of testosterone reduced due to the introduction elsewhere), some reported side effects aggression / rage, confidence / courage. Marijuana Marijuana is from the plant Cannabis Sativa, the psychoactive ingredient THC (tetra hydro cannabinol). Increases heart rate and intensifies the perception of colors and sound, a decrease sense of time may appear to drag on. Impairs transfer of short term memory into long term memory.

Physiology of Drug Effects - Mechanism of Action

Psychoactive drugs primarily have their effect at the synaptic level, increasing or decreasing the release of neurotransmitters, blocking their re-uptake or changing the effect on the receiving cell or by binding to the receptor site that would ordinarily be triggered by a neurotransmitter or neuro-modulator.

Cocaine for example increases the level of nor-epinephrine and dopamine in the brain by blocking the re-absorption of these substances, it may also increase the transmission of serotonin (Rocha et al., 1998).

Alcohol interferes with the work of serotonin on memory, information stored before a drinking session remains in tact during the session but is retrieved more slowly (Stempel, Beckwith and Petros 1986).

Other synthetic drugs such as MDMA "Ecstasy" may cause permanent damage to cells that produce serotonin (Ricaurate et al., 1988).

Tolerance

Use of psychoactive drugs such as heroin and tranquilizers may lead to tolerance - over time more of the drug is needed to produce the same effect - discontinued use may result in withdrawal symptoms such as stomach cramps, nausea, muscle spasms sleep loss and depression.

THEORIES OF HYPNOSIS

Disassociation Theory (Ernest Hillgard 1977, 1986).

Like lucid dreaming, one part of the brain splits off and operates independently from the rest of consciousness, a part of the brain not subject to hypnosis is watching as a hidden observer but not participating.

A related theory is that there is a disassociation between the executive control system (frontal lobes?) and the rest of the brain. The executive part relinquishes control over the subordinate regions. Flaw: circular reasoning - we know that the person is hypnotized because they are suggestible.

The Socio-cognitive Theory The individual plays along and gets caught up in the role, in addition to wanting to please the hypnotist, the individual even convinces him or herself of the situation. Flaw: Hypnosis is more of a trance-like state than is conscious pretense and acting.