upper limb

How do you decide when to stop doing something?


ResearchBlogging.org
There are plenty of times when it’s easy to give up on doing something – just ask me to do the vacuum cleaning or do a workout at the gym! On the other hand, there are plenty of times when someone close to me sighs and asks ‘How long are you going to be?’ while rolling his eyes skyward as I take yet another photo! So, take it from me, I think how long I persist at doing something entirely depends on what it is – oh and the context. I somehow don’t think my dislike of vacuum cleaning would stop me from doing the whole house if a gun was being held to my head. I might even run if there was a fire to run from!

This paper explores an area of task persistence that I’m fascinated with – how mood and ‘stop rules’ influence whether someone stops doing something, or carries on. Stop rules are rules that people apply to whether they persist with a task, or give up – one rule could be ‘as much as can’ or ‘Am I happy with the result of my effort?’, while another could be ‘feel like stopping’ rule, or ‘Am I enjoying doing this?’.
Because our mood can influence whether we are enjoying something or not, if we are feeling a bit disgruntled or low, we’re more likely to stop if we use the latter rule because we’re more likely to feel that it’s not enjoyable to carry on. On the other hand, if we’re feeling quite chirpy, we may feel happy about how well our efforts have turned out, and stop working on the task.

This study by Karsdorp and colleagues, based at the Maastricht University, The Netherlands, manipulates mood and stop rules on task performance. Participants were people with upper limb pain, and were asked to carry out two physical tasks consisting of moving a weighted handle – one with their painful upper limb, and one with their nonpainful lower limb. Just prior to carrying out this task, pariticpants were asked to remember and give a detailed description of a positive or a negative event they had experienced in their life. Their experience was heightened by the interviewer asking for emotion-laden comments and descriptions, and lighting and music were also used to augment emotions. The stop rules were (1) ‘perform the task and ask yourself ‘have I made as many movements as I can?’ If the answer is ‘yes’ then stop, if the answer is ‘no’, then continue. Stop when you are convinced you did as many movements as you possibly could make. There is no right or wrong time to stop.’ (As many as you can rule) or (2) ‘as you perform on the task, ask yourself, ‘Am I enjoying this task?’, if the answer is ‘yes’ then continue. If the answer is ‘no’, then stop.’ Between the upper and lower limb tasks, participants were played the music that was used to heighten their emotional state during the interview section. For the detailed description of the methodology, read the paper itself – it is an elegant design, and well-described.

In addition to these variables, participants also completed a VAS (visual analogue scale) for mood and pain, and several other questionnaires were also included to measure areas such as mood, catastrophising, and pain-related fear.

What happened?
Well, firstly, it didn’t matter whether the task was upper or lower limb (ie painful or nonpainful limb), the results held true for both, and it didn’t matter whether the tasks were carried out in any order – again, the results held true. What was found was that people in a positive mood make more movements than those in a negative mood (now that’s not entirely surprising, if I’m feeling bad I really do NOT want to do the vacuum cleaning!); people who were explicitly asked to ‘do as much as you can’ made more movements than those who were asked to ‘do it as long as you enjoy it’. As well, people with high pain-related fear also performed fewer movements than others, irrespective of mood or stop rule.

What are the points raised by this study? Firstly, mood doesn’t seem to influence stop rule performance, what does influence performance is pain-related fear. Pain intensity doesn’t make a difference to performance (hence why pain reduction as a goal is not one of my priorities as I work to help people return to functional activities); but the type of stop rule itself does have an effect on performance – if I’m told to ‘do as much as I can’, I’ll probably do more than if I’m asked to do something ‘as long as I enjoy it’. This suggests that current goals – or the why am I doing this task? – might play an influential role on how long a person will persevere with a painful task. This might even over-ride the fear of pain in some people, meaning that where people feel they have less option, they may continue with a task even though they are fearful of it. But if a person is feeling low in mood, and persists with a task depending on how they’re feeling emotionally – their performance may suffer.

What does this mean?
Well, it might be an important aspect of how we might frame a goal such as returning to work. We might need to think about whether we ask the person to return to a work as ‘do as much as they can’ or ask them how they’re feeling about their return to work. Cognitive therapists among us might need to consider helping people recognise how transient mood states can be, and help people reframe their goals in the light of setting a target time or number of activities. The transient nature of mood states was highlighted in the discussion section of the paper where the authors indicate that the mood induction effect vanished rapidly – moods returned to baseline very quickly. This could be a confound in the experimental design – and there is a difference between the duration of a low mood arising from depression and that from recalling a sad experience.

What this study does do is highlight the effect that contextual factors like mood and stop rules strongly influence task performance. We may need to keep this in mind as we look at how people we structure activity experiences for people participating in rehabilitation.

Karsdorp, P., Nijst, S., Goossens, M., & Vlaeyen, J. (2009). The role of current mood and stop rules on physical task performance: An experimental investigation in patients with work-related upper extremity pain European Journal of Pain DOI: 10.1016/j.ejpain.2009.07.003