In Feb 2015, the photo of a striped dress stirred a worldwide internet debate ; now, neuroscientists have further decoded the phenomenon, demonstrating optical illusion is linked to specific brain activation patterns.
For some, it is black-blue, for others, it is white-gold. In a fMRI study, the neuroplasticity group headed by Prof. T. Schmidt-Wilcke solved the riddle of the illusion. In no time at all, the dress had captured the attention of media and scientists worldwide. Many research institutes have explored the phenomenon from various angles, by analyzing psychophysics or details of the image components. Bochum researchers Lara Schlaffke, Lauren Haag and Anne Golisch now expanded previous findings by providing insights into the differences in human brain activity caused by the contrasting perceptions.
In the control fMRI condition, participants looked at coloured squares with the same colour properties as the photo of The Dress. In this control condition, no differences between the groups were identified in correctly naming the colours of the squares, nor in brain activation during the presentation of the coloured squares.
Subsequently, they analysed the brain activation in both groups during presentation of The Dress. In a direct comparison of groups the photo triggered differential brain activation, depending on their perception. All participants who saw the dress as white-gold presented additional activation, mainly in frontal and parietal brain areas. Frontal regions are particularly involved in higher cognitive processes such as selective attention and decision making, while parietal areas process visual information from the occipital lobe.
The phenomenon of The Dress provides a unique approach to researching visual illusions: for the first time, scientists had the opportunity to study a control group in a case of ambiguous perception. Before, no optical illusion existed with exactly 2 competing perceptions which could not be deliberately manipulated. By means of this phenomenon, the Bergmannsheil research group succeeded in identifying brain areas which cause optical illusions. http://www.alphagalileo.org/ViewItem.aspx?ItemId=157356&CultureCode=en
Recent Comments