Dr. Nasir Sulman
Department of Special Education
University of Karachi
Nail biting is the habit of biting one’s fingernails or toenails during periods of nervousness, stress, hunger, or boredom. It can also be a sign of mental or emotional disorder. The clinical name for nail biting is chronic onychophagia.
It occurs in:
- 28% to 33% of children ages 7-10 years old,
- 44% of adolescents,
- 19% to 29% of young adults and
- 5% of older adults
- It is more common in young males
Obviously from the facts it shows the most common age would be around the age of puberty when the emotions are high and complex. There would be a rollercoaster of new feelings and pressure from peers which would cause many anxieties and fears and therefore the habit may begin. It makes the sufferer feel some sort of relief by keeping the nervous system intact which would give off a feeling of comfort or even relax them, even if it is only for a short period of time. This habit or obsession depending on the individual is uncontrollable and comes very natural to them, being conditioned from earlier years. In most cases it is done without the sufferer even knowing they are doing it, they would often be in a trance like state during the procedure. Often people do it while they perform their daily activities i.e. reading a book, watching the television or even while socializing with friends and will often stop what they are doing to give more attention to the habit.
As it is mildly related to the obsessive compulsive disorder area of psychology, that too would explain a little more about the behaviour. Obsessive compulsive disorder (OCD) is the name given to a condition in which people experience repetitive and upsetting thoughts and/or behaviour .
Biting the nails can result in the transportation of germs that are buried under the surface of the nail into the mouth. In fact, nail salons use tools that potentially affect a human in a similar way. If [nail tools, such as files] are used on different people, these tools may spread nail fungi, staph bacteria or viruses. Thus, one can see that many pathogens have the ability to “live” inside of a nail, and because of this biting the nails can potentially cause health issues.
A compulsive nail biter could also be tempted to bite not only the nail, but also the surrounding skin and cuticle, possibly breaking skin. Broken skin is susceptible to microbial and viral infections. These pathogens can be spread between the fingers and toes via the mouth. A normal, healthy (nail biting) person has a very low risk of suffering from infections.
Nail biting also has the negative side effect of restraining the use of the hands. A compulsive nailbiter can be restricted in their ability to work (i.e. writing, typing, drawing, playing stringed instruments, driving) because of the damage done to the nail or surrounding skin and/or anxiety in regards to the appearance of their nails.
The sufferer would rarely think about the consequences when they are biting their nails i.e. bad grooming, unattractive hands or feet, sores and redness around the area of the nail. This could cause more anxieties as the person would feel like they have to clean up all those rough bits around the nail to make them appear less unattractive. In more extreme cases the sufferer would be prone to get mouth infections from bacteria or germs under the nail being transferred from the nail to the mouth, or oral disease’s being transferred into the broken skin around the area of the nail causing infection and swelling. They could also scratch areas of broken or infected skin on their bodies thus spreading the infection to the mouth or hands. Some sufferers would keep their hand out of view from people around them to try and hide their embarrassing habit. If the person carries this habit into their adult life it can lead to dental problems like gum disease and with years of compulsive biting eventually damaging the teeth. This can be irreversible. With all this in mind it can be a huge social embarrassment to them and could cause their social life to suffer as a consequence not to mention their self esteem. It can also have an impact on their work lives too as they are restricted to jobs that suit them, working with computers, driving and writing. This would be more stressful to the sufferer as it would make the job somewhat difficult. This again is also likely to cause more anxiety and therefore the behaviour pattern is repeated.
Many theories have been proposed to explain the etiology and maintenance of nail biting. One common causal explanation suggests at nail biting is evoked by states of “tension” or “anxiety” (Hadley, 1984). In fact, nail biting is typically referred to as a “nervous” habit, implying it is a function of a specific physiological or emotional state. Unfortunately, little empirical research is available on the topic. Results of the few existing studies have been mixed with respect to the relationship between anxiety and habit behaviors, a category that includes nail biting (Deardorff, Finch, & Royall, 1974; Klatte & Deardorff, 1981; Woods, Miltenberger, & Flach, 1996).
A second theory, known as “environmental restriction” (Schendler, cited in Hadley, 1984), suggests that limiting motoric activity evokes habits such as nail biting. Said another way, activity restriction is thought to function as an establishing operation (Michael, 1993) which increases the reinforcing value of stimulation produced by any behavior, including that provided by nail biting. Thus, the environmental restriction theory would predict an increase in nail biting under conditions of low motoric activity. Indeed, some research supports this theory. For example, Harlow and Harlow (1962) found that a monkey raised in virtual isolation developed “compulsive habits” and would “chew and tear at its body until it bled.” In addition, Berkson and Mason (1963) found that individuals with mental retardation were more likely to engage in stereotypic behavior or self-manipulation when in situations deprived of environmental stimuli. Although these studies seem to support the environmental restriction theory for habitual behaviors in some populations, the generality of the theory has not been tested with respect to nail biting in typically developing humans.
Combining the two preceding theories, the “arousal modulation theory” suggests that nail biting calms the individual during periods of autonomic arousal and provides stimulation in times of inactivity (Hansen, Tishelman, Hawkins, & Doepke, 1990). Although all three of the aforementioned theories are plausible, no one has garnered more empirical support than the others. Taking this into consideration, one could conclude that nail biting is not caused or maintained by one variable across all individuals. Indeed, nail biting may be maintained by different variables across individuals. If this is the case, it would be necessary to determine nail biting function on an individual basis.
Specific functional assessment/analysis technologies have been developed to assess variables maintaining self-injurious behavior in persons with developmental disabilities (Iwata, Dorsey, Slifer, Richman, & Bauman, 1982). Using such procedures, individuals are exposed to conditions designed to examine reinforcing variables associated with occurrences of a target behavior. In each condition a reinforcing variable thought to maintain the target behavior is manipulated, and the effect of the reinforcement on the target behavior is observed. Variables traditionally tested in the functional analysis of self-injury include social attention and escape from a demanding task. Automatic stimulation produced by the target behavior (Iwata, et al., 1982) can also be evaluated by observing high levels of the target behavior when the individual is left alone or when the target behavior is elevated across all functional analysis conditions.
Treatments for this behavioural condition depending on the severity vary. It requires determination and commitment from the patient and support from their family would be great help too. The first and most common approach people could take would be the non therapeutic treatments. Most parents trying to get their child to stop would coat the nail with a polish that has a bad taste, often this would stop the child but only as a temporary means. Adults or teens could try getting regular manicures to keep them neat and presentable or use artificial nails to protect the nail and help it grow.
To understand the psychological nature of this problem in detail let’s take a look at the procedure on a deeper level. Nail biting according to behavioural psychologists is an operant conditioned habit. This would be a behaviour that the person can physically control. As all behaviour’s are learned they can be unlearned. It is a type of learning in which the behaviour is influenced by its consequences (Skinner 1938, 1953). With nail biting the consequences would be the feeling of being relaxed or less agitated, this to the sufferer would be a positive feeling and therefore it is more likely to be repeated. This is how the conditioning starts. If the result of the biting produced a negative feeling the habit is likely to decrease over time. Operant conditioning has three different events that occur, the ABC’s. Firstly the antecedents (A), this would be where the emotional or mental problem i.e. worries or stresses are present. Secondly is the behaviour (B), this would be the reaction to the first event and that in this case being the nail biting and thirdly would be the consequence (C) that again would be the relaxed feeling. The connections of the events are also called contingencies, where each step depends upon the next. The emotional or mental problem being present causes the nail biting to occur and the consequence being more relaxed about the initial problem but not making it go away.
There are two types of behavioural therapies for this pattern, one being Habit Reversal Training and the other being Stimulus Control therapy. Habit Reversal Training (HRT) was developed in the 1970’s by psychologists Nathan Azrin and Gregory Nunn for treating nervous habits such as nail biting that are done automatically (OCD Action 2006). It is a procedure that involves a few steps stopping the bad habit by replacing it with a less harmful habit. It involves a breakdown of the behaviour and what causes it. Sufferers for example could keep a diary of when the habit is occurring that way they can identify the stimulus and therefore have a better understanding of it and then try to work on that area in more detail. That could involve trying to avoid or change thoughts or actions that trigger the reaction by replacing them with less negative thoughts or actions. Relaxation is another method of this therapy which can also be great help as it teaches the patient to centre themselves and have more self control and has a part to play in the overall procedure. The second therapy, Stimulus Control Therapy is used to both identify and eliminate the stimulus that frequently triggers the biting urges (OCD Action 2006). With the stimulus being emotional or mental the patient could concentrate on what initially sets off this behaviour, counselling or psychotherapy would be very helpful in this area as it would help the patient deal with the emotions in a positive and constructive way. The aim in this therapy is to be aware of what triggers it off and consciously try to change it.
In summary, nail biting is a bad habit that is most common in teens and early adults. The side affects are unattractive and can cause embarrassment. It occurs in almost half of them around the age of puberty and as people grow out of puberty most commonly they also grow out of the habit. It is not a serious mental or psychological condition and can be treated if the person really wants to treat it. This would involve motivation and commitment. It is a behaviour that is learned and controlled by the individual and can be reconditioned at any time.
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