The Self-Monitoring Of Habitual Knuckle Cracking

The Self-Monitoring of Habitual Knuckle Cracking and a Proposed Intervention Knuckle cracking (KC) is the manipulation of the fingers which results in an audible crack at the joint, and is often done habitually. KC is a very common behaviour, and studies show that this is because it feels good due to the stimulation of the nerve endings around the joints. Between 25% and 54% of people are thought to crack their knuckles (depending on the population studied), and men tend to do this more than women (deWeber, Olszewski & Ortolano, 2011). KC can become habitual because of the positive outcomes such as the immediate release of tension at the joints, and the subsequent increased range of movement.

However, the negative outcomes of KC entail the potential development of a weak grip, and soft tissue swelling. Azrin and Nunn explain in their 1973 study that nervous habits such as KC persist due to response chaining, limited awareness, excessive practice and social tolerance. (Azrin & Nunn, 1973). American psychologist Dr. Marie Hartwell-Walker claims that the most common reason for KC is to release nervous energy ("Nervous Habits: “Cracking” Your Knuckles | Ochsner Health System", 2018).

The act of KC increases the space between the joints and decreases the intra-articular pressure. When the joint is manipulated to its limit, joint fluid rushes into the areas of negative pressure. The larger bubbles of gas suddenly collapse into microscopic bubbles, which is what causes the characteristic cracking sound. This process leaves the joint space wider than it previously had been and synovial fluid more widely distributed, in addition to leaving the joint with a wider range of motion (Yildizgören et al. , 2017). After approximately 15 minutes, the joint space has retracted back to its original position, and the knuckles can be cracked again. It is a common myth that KC leads to arthritis in the hand joints, however, there is insufficient evidence to support this claim (Swezey & Swezey, 1975, Castellanos & Axelrod, 1990).

Various behavioural techniques have been utilised in the treatment of nervous habits such as KC. Azrin and Nunn (1973) conducted an experiment to treat nervous habits such as shoulder-jerking, head-shaking, eyelash-plucking, nail-biting, and thumb-sucking. All incidences of the nervous habit were recorded by each of the 12 participants, both before and after treatment. The habit reversal method was applied according to each individual nervous habit. For example, those who felt the urge to suck their thumbs, would instead clench their fists to avoid performing that behaviour. It was found that the habit reversal training reduced the amount of nervous habits by about 99% by the third week, and was therefore concluded that the habit reversal procedure was an extremely effective method of eliminating nervous habits (Azrin & Nunn, 1973).

The habit reversal procedure consists of five components: (1) awareness training, (2) competing response training, (3) relaxation training, (4) social support procedures and (5) habit inconvenience review (Finney, Rapoff, Hall & Christophersen, 1983). Many authors have attempted to determine which components are essential for the desired effect, and eventually it was found that the awareness training and the competing response training used in conjunction with each other were the most effective in suppressing nervous habits (Miltenberger, Fuqua, & McKinley, 1985, Woods & Miltenberger, 1995). In Miltenberger, Fuqua, and McKinley’s (1985) study, nine subjects with various muscle tics were divided into two groups. One group was treated with just awareness and competing response training, and the other group was treated with the whole habit reversal procedure, to determine which method was most effective. Tics were observed and measured by videotaping the subjects in a clinical environment designed to evoke their individual tic. It was found that the awareness and competing response components of habit reversal can decrease nervous habits to the same degree as the entire habit reversal program (Miltenberger, Fuqua & McKinley, 1985).

Following this study, Miltenberger and Fuqua (1995) conducted an experiment to test the effectiveness of a contingent versus a non-contingent practice of the competing response procedure. Nine subjects recorded the daily frequency of their respective nervous habits, before being divided into two groups; one group was instructed to engage in the competing response contingent on each occurrence of the target behaviour, and the other group in a non-contingent fashion. It was found that the non-contingent competing response was largely ineffective in decreasing the nervous habits, whereas the contingent competing response procedure greatly reduced the nervous habits of most subjects. The results should be interpreted with caution, however, because the data were self recorded and direct assessment of their accuracy was impossible to attain.

This research indicates that the competing response procedure is most effective in decreasing nervous habits when used in a contingent fashion (Miltenberger & Fuqua, 1995). All of these behaviour-modification studies were taken into consideration when writing this paper, the aim of which is to create an intervention to eliminate the behaviour of habitual KC (N = 1). Method A 19-year-old Caucasian female undergraduate student (X) participated in a behaviour monitoring program. Her part time job is in a fast-paced work environment where multi-tasking is essential. She was required to participate in this program for an undergraduate level psychology class. The behaviour was recorded using an event recording method through a self-monitoring process over the period of 10 days. An instance of the behaviour was recorded if pulling, bending, twisting, or applying pressure to one or more fingers resulted in a cracking sound in from knuckles.

This did not include the cracking of any other joints in the body. An event recording method was used because it documented each time the behaviour occurred. This method takes place during a specific time period to see a pattern in behaviour; for this experiment, the time period typically spanned from 7:30am-10pm over several days. Recording behaviour with this method was done so by writing down each occurrence on a piece of paper. The behaviour being recorded, KC, has a clear beginning and end, and does not occur at such a high rate that it is hard to monitor. Where and when the behaviour occurred, as well as who was present and what was happening both before and after, in order to make correlations later on. Results and SORCK analysisThe frequency of KC tended to increase and decrease from nine to 16 instances per day over the 10-day period, with a mean of 13. 4, and a range of 7. Figure 1 illustrates the trend in KC that occurred over the 10-day monitoring period.

The fluctuation of data scores occurred as a result of context at the time of recording. The highest frequency of 16 occurred four times across the 10-days. This is most likely due to X experiencing high levels of stress and anxiety on days three, four six and eight, as well as day one (which had a frequency of 12). These days tended to be days when X was either at university or work. Subsequently, the low frequencies of nine and 11 recorded instances of KC occurred on days when X did not experience high levels of stress and anxiety (days 2, 7, and 9). The general trend from days four to nine is a slight decline, and this could be due to the increased awareness that X was feeling when monitoring this behaviour; the awareness caused a conscious attempt to reduce the frequency of KC. External factors such as people who were present did not affect the frequency of KC. The frequency of KC tended to increase and decrease from nine to 16 recorded instances over the 10-day period. There were no obvious outliers in the data.

After it became a habit, KC was used as a way to subconsciously release nervous energy and stress. ContextualKC usually occurs immediately after waking up and during the day, specifically at work and when writing assignments. This behaviour usually happens when driving, on public transport, writing, reading, or during tutorials and lectures. People who are present when KC usually occurs are family, colleagues, and the public, but mostly no one. Immediate Immediately prior to KC, feelings of anxiety or stress are prevalent. This could be from a fast-paced work environment, assignment pressure, an important conversation, or a busy highway.

The subject strives for academic perfection and often worries about exams and assignments. Despite this, she is extremely prone to procrastination. Thus, she is frequently overwhelmed with feelings of anxiety, uncertainty, and stress. the subject’s mother takes medication for depression and anxiety. The subject is also predisposed to KC when she is frustrated or nervous.

The pulling, bending, twisting, or applying pressure to one or more fingers resulting in a cracking sound in from knuckles. This does not include the cracking of any other joints in the body.

Immediate

• Release of joint tension
• Increased range of motion
• Release of nervous energy
• Negative comments made by others about the unpleasant sound associated with KC
• Feelings of self consciousness about the behaviour
• Slight reduction of anxiety levels

Long Term

• Weak grip
• Soft tissue swelling

Positive punishment Participant X is a 19-year-old female who has suffered from habitual knuckle cracking for the last 12 years. Historically, X reported that her KC commenced in childhood through imitation of her father, and was most likely around the time she had to move schools (which resulted in her having to make new friends).

Contextually, X’s KC occurs when around his family, colleagues, and when she is alone. It also occurs in tutorials and lectures, and when she is either on the bus or driving to university. X reported that she feels anxious, stressed, frustrated and nervous at times just before and when she is KC. X reported that she tends to be a very stressed person, constantly strives for academic perfection, yet is a frequent procrastinator, and has a mother who suffers from anxiety. X reported that when she cracks her knuckles, she often feels a slight relief from stress, anxiety, frustration, and nervous energy, but also feels guilty and irritated due to other people commenting on the unpleasant sound. Thus, the relief that X feels when she cracks her knuckles appears to outweigh any sort of guilt and irritation she feels and thus is maintaining KC.

Discussion

The aim of this study was to monitor the behaviour of habitual KC over a 10-day period in order to develop a proposed intervention to eliminate the behaviour. When correlating the data with the SORCK analysis, it was found that when X experienced high levels of stress and anxiety, the frequency of KC increased. The participant experienced consequential negative reinforcers, such as the release of joint tension, the release of nervous energy, and the slight reduction in stress and anxiety levels. The participant also experienced subsequent positive punishments, such as negative comments made by others about the unpleasant sound, and feelings of self consciousness about the behaviour. Other such contingencies included the important contexts in which KC was recorded.

For example, when X was in a work or university environment, frequency of KC was significantly higher than in a low-stress environment, such as at home. These findings were consistent with the literature, which states that people tend to crack their knuckles when they experience stress or need to release nervous energy. The intervention that would be most effective to treat KC for participant X would consist of the competing response component of the habit reversal program, would be performed in a contingent fashion, and would follow a fixed-ratio schedule for each phase. This is in accordance with Miltenberger and Fuqua’s (1995) study, which determined that a contingent procedure of the competing response training is the most effective method for seeing a decrease in nervous habits. The aim of this intervention would be to eliminate the occurrence of KC completely. When the urge for KC occurs, X will immediately clench their fists in order to avoid the behaviour. Once the urge has passed and KC has not occurred, X will immediately receive a positive reinforcer by means of a reward (one m&m).

However, if KC does occur, X will immediately receive a positive punishment by means of snapping a rubber band across the wrist. During phase one, X will receive a reward every time KC is avoided by competing response training, and a punishment at every occurrence of KC. Once KC has reduced to 10 times per day, phase two may commence. During phase two, X will receive a reward after every two times KC is avoided by competing response training, and receive a punishment every time KC does occur. Once KC frequency has reduced to five time a day, phase three may commence. During phase three, X will receive a reward after every 3 times KC is avoided by competing response training, and receive a punishment every time KC does occur. This phase will continue until KC frequency has reduced to 0 times per day, at which point the intervention will be complete, and the nervous habit of KC eliminated. There are a number of limitations to this intervention.

Firstly, the different timing for each phase and the intervals for rewards and punishments can be very complicated. It is possible that some of the specific details may be forgotten by the subject, which would then impact the schedule and, therefore, the efficacy of the intervention. In addition to this, the participant is the one rewarding themselves, and they may take advantage of this and manipulate their behaviour in order to receive the reward, instead of actually conditioning themselves to eliminate the habitual behaviour. Furthermore, having the reward timed so closely to the clenching of fists poses the risk of X wrongly associating the reward with the act of clenching their fists, and not the avoidance of KC. Moreover, the self-reporting method of monitoring the KC behaviour is a limitation to the project, as it is highly unreliable in obtaining an objective assessment.