Toronto, May 31 (IANS) The brains of people who have been depressed can show whether they are likely to relapse, especially if they are experiencing mild sadness.

‘Part of what makes depression such a devastating disease is the high rate of relapse,’ said study leader Norman Farb, doctoral psychology student at the University of Toronto.

‘However, the fact that some patients are able to fully maintain their recovery suggests the possibility that different responses to the type of emotional challenges encountered in everyday life could reduce the chance of relapse,’ he said.

Farb and his team showed a group of formerly depressed patients sad movie clips and tracked their brain activity using functional magnetic resonance imaging (fMRI). Sixteen months later, more than half of them had relapsed into depression, according to a Toronto statement.

The researchers compared the brain activity of relapsing patients against those who remained healthy and against another group of people who had never been depressed.

Faced with sadness, the relapsing patients showed more activity in a frontal region of the brain, known as the medial prefrontal gyrus.

These responses were also linked to higher rumination – the tendency to think obsessively about negative events and occurrences.

The patients who did not relapse showed more activity in the rear part of the brain, which is responsible for processing visual information and is linked to greater feelings of acceptance and non-judgement of experience.

‘Despite achieving an apparent recovery from the symptoms of depression, this study suggests that there are important differences in how formerly depressed people respond to emotional challenges that predict future well-being,’ says Farb.