A walk in the park is effective in helping people cope with depression, research says.

Researcher Marc Berman and colleagues report that interacting with nature improves cognitive function of people and helps them concentrate on a task.

“Our study showed that participants with clinical depression demonstrated improved memory performance after a walk in nature, compared to a walk in a busy urban environment," Berman said.

For the study, 20 participants were randomly assigned in two groups; the first group was asked to walk in a park and the other in a busy street. All the participants in the study had been diagnosed with clinical depression and prior to the field test they were given a test to assess their cognitive and memory skills and mood status. They were then asked to think about a painful self-reported memory.

After the walk, both groups were given a test to determine their cognitive and working memory ability and a test to assess their mood. The same procedure was repeated after a week with both groups switching walk-routes (park or busy street).

The team found that there was 16 percent improvement in the cognitive and memory test when the participants walked in a park than a busy street. The change in mood status of both the groups was significant and similar in both settings.

According to experts, walking alone in nature may actually induce negative thoughts or rumination among people suffering from major depression.

World Health Organization reports that close to 121 million people suffer from depression worldwide and that fewer than 25 percent of these people have access to effective treatment.

Depression can be diagnosed in primary care but the lack of qualified people and more importantly, the stigma attached with being depressed keeps people from finding treatment for the condition, says World Health Organization.

A study published in British Journal of Sports Medicine links aerobic exercise to mood improvement in people diagnosed with depression. The study says that aerobic exercise improves mood in a short time.

Experts feel that more research based on a large study group is required to understand how physical activity affects people with depression.

"Walking in nature may act to supplement or enhance existing treatments for clinical depression, but more research is needed to understand just how effective nature walks can be to help improve psychological functioning," Berman said.

The study is published in Journal of Affective Disorders.