People with depression often feel their life is out of control. It can evoke feelings that their life is pointless or by merely existing bad things can happen. Research funded by the Economic and Social Research Council (ESRC) suggests that these feeling may be caused by subtle changes in the way depressed people perceive time and process their surroundings.
Experiments by psychology researchers Dr Rachel Msetfi from the University of Limerick, Ireland, and Dr Robin Murphy at the University of Oxford in the UK, used a computer-based task to explore how healthy as well as depressed volunteers responded to simple tasks in which they had varying levels of control.
They were asked to test the reliability of a remote controller in different rooms of a virtual house. The remote would switch on the hi-fi in each room with a certain level of reliability; sometimes the music would come on immediately, sometimes with a slight delay and sometimes it would start even when the volunteer decided not to use the remote.
The experiment was designed so that in different rooms the volunteers had different levels of control. In some rooms pressing the remote control worked well. In other rooms the remote was less reliable, giving the volunteers less control. After many goes at using the remote controller in a room each participant was asked about how much control they felt they had using the remote, and the extent to which the behaviour of the hi-fi was governed by the room, not them pressing the button.
Dr Msetfi's analysis showed that when there were longer delays, either between opportunities to press the remote button or between pressing the button and the music turning on, depressed people responded differently than others. Interestingly, with these longer delays, their judgements were actually more realistic than those of the healthy volunteers.
This finding supports other studies which suggest that people with depression experience time as passing more slowly; they also tend to process cues from their environment and context differently to people without depression.
"When depressed people have more time to process information about cause and effect, due to their slower perception of time they tend to take more notice of their environment which is often beyond their control, hence their feelings of helplessness," says Msetfi. "We see that contrary to the cognitive theory of depression, which emphasises the effects of irrational thought, here very subtle changes in perceptions have a strong knock on effect on other cognitive processes and feelings of control."
Msetfi also suggests that her research may also help to explain why mindfulness therapy is so successful in treating depression and preventing relapse. "Mindfulness is about paying more attention to what is happening right now. If time moves more slowly for people with depression and makes them oversensitive to their surroundings, mindfulness may work because it recalibrates their perceptions to find a better balance."
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Study: 'Feelings of control: The effects of depression, context and contingency learning'