Individuals which undertake a 4 day journey in the nature score in creativity test much better with a 50% increase. It results in a clear measurable improved performance effect in tasks that require creativity.
High order cognitive functions including selective attention, problem solving, inhibition, and multi-tasking are all heavily utilized with modern technologies. Exposure to nature can restore prefrontal cortex-mediated executive processes like these. The exposure to natural setting appears to replenish some, lower-level modules of the executive attentional system. A four days of immersion in nature, and the corresponding disconnection from multi-media and technology, increases performance on a creativity, problem-solving task by a full 50%. Therefore there is a cognitive advantage to be realized if we spend time immersed in a natural setting. The advantage comes from an increase in exposure to attention demanding technology, which regularly requires that we attend to sudden events, switch amongst tasks, maintain task goals, and inhibit irrelevant actions or cognitions [http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0051474].
Back to the nature!
However, it is not possible to conclude that nature is the primary cause of creativity boost. An alternative Explanation is that people just relaxed from daily routine, latter one is the cause of creativity Boost, and nature here is a method to refresh the mind.
It is also actually very important that we always challange ourself with new kind of tasks or environments. There were studies that showed that this counteracts the cognetive decline with Aging.