Positive stimuli and drugs against depression

An additional dose of positive stimuli following a stressful period in combination with good medication focusing on the stress system can prevent depression. This is the conclusion of a study on stress in mice and humans by Sergiu Dalm. Defence on 21 November.

Positive stimuli

People are increasingly developing depression in response to chronic stress. Dalm studied stress in mice and in humans. His conclusion: chronic stress leads to rigidity of behaviour in both species. One of the big problems is that people who suffer from stress no longer respond adequately to positive stimuli. Dalm: ‘My research shows that if you administer positive stimuli following a stressful period, and if you prescribe drugs focusing on the stress system, the negative effects of stress can be undone.’

Less flexible

Stress leads to changes in behaviour both in mice and in humans, as shown in Dalm’s research. ‘Stress changes the way people think; they assess their environment in a different way. They become less flexible in solving problems and focus primarily on potentially dangerous stimuli. This shift in processing negative and positive stimuli leads to a diminished reaction to positive stimuli. Which in turn leads to more stress – and even to depression.’


According to Dalm, a great deal can be achieved with good medication. ‘I show that this new medication, which focuses on the stress system, in combination with additional positive stimuli, might be successful in dispelling the negative effects of depression much faster.’

For this reason, Dalm now wants to further test the medication and dosage schedules. ‘And study whether and when a relapse takes place after treatment with this medication and the presence of additional positive stimuli.’

(20 November 2012 - MH)

Health, Life and Biosciences is one of the 6 research themes of Leiden University.

Health across the Human Life Cycle is one of the 6 research themes of Leiden University.

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Bachelor's (in Dutch)

Bio-pharmaceutical science
Bio-medical science


Biomedical Sciences
Bio-Pharmaceutical Sciences
Clinical Psychology

Last Modified: 22-11-2012