Sleep duration, quality, dreaming......

Misconceptions about many aspects of sleep, including its duration are highly prevalent in the community. Sleeping for lesser duration is equated with evidence of hard work. There is no fact in this. An adolescent aged 14 or 15 years has to sleep at least 9 hours a day according to most experts. But will any child who is to appear for CBSE / SSLC be permitted to sleep this much ?
In reality, there is wide variation in the sleep requirement of individuals. Some can function without any problem even by sleeping for 4 or 5 hours. But generalizing this to the whole population will only lead to unnecessary conflicts. Advancing age reduces the need for sleep as well as results in fragmented and poor quality sleep.
Among the stages of sleep about 25% of time is spent in REM sleep and 75% in Non REM sleep. About 25 to 30% of the Non REM sleep is spent in superficial stages I and II. Usually this portion of sleep can be dispensed off without much adverse consequences. This is what is done by most short sleepers. They enter in to the deeper stages of Non REM III and IV within few minutes of sleep onset. The minimum time of sleep needed may vary from 4.5 to 5.5 hours. This is roughly the time spent in Non REM Stages III, IV and REM together. Reducing the time spent in these stages can lead to sleepiness, poor concentration, impaired work performance, accident proneness etc. If such a deprivation is prolonged mental or physical disorders can occur.
Dreams mostly occur during REM sleep. Dreams may occur in SWS also, but these are less likely to be remembered. It is usual for the sleep to be disturbed by dreams after being deprived of proper sleep the previous night. This is due to rebound of REM sleep. The body tries to compensate for the lost REM sleep by more frequent bursts in the succeeding night.

Dreams were thought to have symbolic meaning. This idea attained maximum scientific attention after Sigmund Freud's book 'The interpretation of dreams'. But now, neuroscientists and psychologists do not give much importance to the content of dreams in understanding the mental life of a person.

Sleep......

Sleep is a behavior seen in almost all animals. We spend around one third of our life time asleep. Prolonged sleep deprivation can lead to severe mental and physical problems and result in death. Lack of proper sleep can lead to reduced immunity, impairment in memory, reduced alertness and clarity if thinking. Disturbances of sleep are commonly found in majority of psychiatric disorders.
Generally people think of sleep as a uniform state. But studies using electrophysiological equipments have shown that sleep can be divided into distinct stages which occur in a predictable sequence. This pattern is referred to as sleep architecture.
Sleep can be defined as a state of rest with reduced awareness about the environment that is easily reversible. Thus it is different from other superficially similar states like coma.
Human sleep is subdivided into 2 types based on certain electrophysiological parameters and other phenomena. These are the REM (rapid eye movement) and Non REM sleep. REM sleep gets this name as there are rapid movements of the eye balls during this phase. This phase is associated with vivid dreams.
As one falls asleep the first stage occurring is called Stage I of NREM sleep. Then we successively pass through stages II, III and IV. Each stage has characteristic features on the Electro encephalogram (EEG). Slowing of EEG activity is noted from stages I through IV. Stages III and IV are together called Slow wave sleep (SWS) because the EEG record show considerable slowing during these stages. The EEG of REM sleep shows fast activity resembling the waking record.
REM sleep appears in bursts. At the end of approximately 90 to 110 minutes the first burst occurs. By this time the subject would have progressed to the SWS stages.
Subsequently, the subject moves back to SWS in around 20 minutes. Thereafter the sleep alternates between SWS and REM bouts every 60 to 90 minutes. The person enters the stages I and II of NREM only if wakes up again. Otherwise the rest of night is spent in SWS and REM sleep only.
Sleep is essential for growth and repair of the body, consolidation of memory and many other unknown functions. The secretion of growth hormone is maximal during sleep in babies, showing the important role of sleep in their growth.

Is addiction a moral weakness?

The only reason to make the distinction [between habit and addiction] is to persecute somebody’ (Szasz, 1973).
The terms addiction, abuse, dependence etc have been used in an imprecise manner by many and this has created some confusion. Lay people still use the term 'addict, addiction' as these are easily understood. But professionals, especially mental health professionals, prefer to avoid these terms for various reasons. One reason is from the angle of political correctness - these terms have pejorative connotations. The other reason is the lack of precise definition, even though these terms have been in use for quite long time. Yet another issue is the trivialized usage. This is when we refer to 'cross word puzzle addicts or exercise addict'. Using the term this way creates a wrong impression that substance use is a problem of similar nature.
Both DSM - TR and ICD - 10 (these are the classification systems used by psychiatrists for diagnosing and classifying mental disorders) use the terms 'substance use disorders' and substance induced disorders'. Substance use disorders include 'substance abuse' and 'substance dependence'. Substance induced disorders include intoxication, withdrawal and other more serious psychiatric conditions.
There are two aspects to dependence - physiological and behavioral. Physiological dependence has two aspects. One is the development of tolerance to the drug necessitating the use of increased quantity over time. The other is the development of a specific withdrawal syndrome on cessation of use.
Behavioral aspects include 1) strong desire or craving for the substance, 2) inability to control the onset, duration, termination or quantity of use, 3) spending lot of time to procure, use or get over from the effects and neglecting other avenues of pleasure due to excessive preoccupation with the substance
and 4) continued despite having adverse consequence (e.g: drinking despite having liver impairment)
It has been argued that it is better to use the term 'neuro adaptation' to the physiological phenomena of tolerance and withdrawal. Therefore, the term dependence is better reserved for the psychological and behavioral consequences.
But this is not strictly adhered to by most authorities. Thus the term 'dependence' continues to include both the physiological phenomena and the behavioral aspects.
The quote given at the beginning is not acceptable to mental health professionals. Dependence is a maladaptive state. It is a significant problem affecting millions all over the world - both the users, their families, employers and the society as a whole. A problem of such magnitude should not be trivialized by comparing with use of common things like food, music, clothes, water or oxygen.
Dependence to substances need not always be thought of from the moralistic angle. A person who is dependent on a psychoactive substance is in a pathological state. It is not like excessive time being spent on music or cross word puzzles. There are no serious physical, mental or social consequences for them. But the serious consequences of substance dependence can be proved with ample evidence. There is no need to be value neutral when one is dealing with a disease condition.
There is definite vulnerability underlying development of dependence. When such a vulnerable person is exposed to the substance, he is at risk for dependence. Social, cultural and psychological factors are also important in shaping the final picture. There may be several others who can have controlled usage. Dependence on substance is not a sign of moral weakness. It is a pathological condition which develops in persons with biological, psychological or social vulnerability, needing proper evaluation and treatment. If untreated, it will lead to serious individual and social consequences. Substance abuse in most cases, is just a prelude to development of dependence. It is always better to intervene at this stage without waiting for development of a full blown dependence syndrome or serious health consequences.

Dr. Vilayanur S Ramachandran talks on the Mind

An excellent talk on 'Brain and Mind' by noted neuroscientist Dr. Vilayanur S Ramachandran is available at this link.

http://www.ted.com/index.php/talks/vilayanur_ramachandran_on_your_mind.html

He disucsses the Capgras delusion, Phantom limb pain and synesthesia in this talk. The 'mirror box' used to relieve phantom limb pain is also shown.

OCEAN of personality

Study of personality based on psychological traits has a quite interesting history. It started with Gordon Allport and Henry Odbert in 1936 who used a very innovative method. They searched an unabridged dictionary for words that could be used to describe persons. They identified around 35000 words. Further analysis was done to eliminate mere evaluative terms (e.g:awful) resulting in 4000 genuine words that can be called words describing genuine traits.
Raymond Cattell identified 35 personality variables from this list of 4000 words. Further empirical testing and analysis (using statistical technique of factor analysis) resulted in 12 personality factors. He could identify a further 4 factors using self report questionnaire. Thus he came up with the 16 personality factors. He also devised test for measuring these 16 factors (16 PF test).
Later the highly influential British psychologist Eysenck argued that only 2 factors are needed to describe the personality These were extraversion - introversion and neuroticism - emotional stability. Though this was widely accepted, there was a feeling that this is not the whole story.
In 1961, Ernest Tupes and Raymond Christal did studies using the 35 factors of Cattell. They produced evidence that a 5 five factor model could fit in well with empirical data and could explain personality. Thus this model was better than Eysenck's 2 factor model.
The utility of this model was confirmed by Norman and Goldberg 20 years later creating renewed interest in this model.
The 5 factors involved are
Openness to experience, Conscientiousness, Extraversion, Agreeableness and Neuroticism. (can be abbreviated as OCEAN)
Each factor has around 5 or 6 underlying traits. These traits have a strong correlation to the adjectives used to describe a person in the natural languages. Studies have been done in Chinese, hebrew, Filipino and several Indo-European languages.
The personality disorders described in DSM - IV can be understood based on the levels of the underlying traits of these 5 factors.