A team led by researchers from the Higher Council for Scientific Research (CSIC) has discovered that the human brain is capable of increasing the resolution of images before processing them , just as a digital camera would. The lateral geniculate nucleus is the part of the brain that receives visual information and sends it to the cerebral cortex for analysis. According to the study, this nucleus also increases the resolution of the images received with a technique similar to that used in photographic editing: the interpolation or filling of the missing information with data invented from a specific algorithm to achieve enlargement of the size of the images. the initial image.
The work, published in the journal Neuron , argues that the eye functions as a photographic device, where the ganglion cells of the retina act as pixels and allow a maximum resolution of one megapixel to be obtained . “The neural circuits that form the nucleus of the brain interpolate to obtain a retinal image with a greater number of pixels and, therefore, a higher apparent resolution”, says Luis Martínez, researcher at the Institute of Neurosciences of Alicante, a mixed center of the CSIC and the Miguel Hernández University.
Increasing resolution through interpolation is common in digital imaging. However, this process has a shortcoming: it reduces local contrast , which makes images look out of focus. In the case of the human eye, this problem is solved thanks to two cell types present in the thalamus that compensate for these adverse effects. The circuits of the retina and the thalamus involved in both operations are generated during embryonic development.
According to the authors, a larger human eye (greater than 25 millimeters) would allow us to see the images with a higher quality and resolution, but this would imply a high metabolic cost and an excessive space for the axons or cables that connect it to the brain.
