The existence of differences in visual processing abilities between men and women has always been a controversial issue. A cognitive level It is believed that there are differences between the two sexes in complex functions such as memory, language, reasoning, planning and problem-solving, as well as perception and action. These so-called higher cognitive functions use information processed by the sensory areas to formulate articulated concepts. For example, several studies have shown that women have a larger and more complicated vocabulary for describing colours and that they memorise them more easily than men, who instead minimise the range of colours in their language. These differences have been observed by various studies that have shown that the way in which the visual centres of the brains of men and women work is different: men have a greater sensitivity to details and fast-moving stimuli, while women are better at discriminating colours.
The way a colour is displayed is influenced by three dimensions: hue, saturation and brightness. Hue is the actual colour: red, yellow, green or blue. Saturation is the depth of the colour: for example, emerald green is more saturated than pastel green. Brightness describes the way a colour radiates or reflects light.
Gender differences in the vision of colour
In research conducted to capture differences in visualisation between the two genders, men and women were asked to describe the hue of a colour and assigned a descriptive percentage to the categories red, yellow, green and blue. The results showed that women are more adept at distinguishing subtle differences between colour gradations than men. This sensitivity was most noticeable with shades of yellow or green. Men were also less able to distinguish shades of colour, especially those falling in the middle of the spectrum, such as yellow, blue and green. In addition, it appears that men need slightly longer wavelengths of light to see the same shades as women; in fact, the shades identified as orange by women were considered more yellow by men.
A explanation of the different ability to perceive colours between men and women lies in the retinal cone photoreceptors and the genes that encode them. The colour visiondepends on three types of cone photoreceptors: those most sensitive to long wavelengths (L cones), those sensitive to medium wavelengths (M cones) and those sensitive to shorter wavelengths (S cones). The genes coding for two of these photoreceptors, L and M cones, are located on the X chromosome where small genetic mutations can occur. If the genes in the male X chromosome are mutated, a lack of colour vision occurs. If a woman inherits a normal X chromosome and a mutated X chromosome, she becomes a carrier of a colour vision defect, with a 50% probability of passing this defect on to her children. The woman may also be a carrier of the genetic defect, but not manifest it due to a mechanism of random inactivation of the X chromosomea normal biological process consisting in the deactivation of one of the two X sex chromosomes.
Gender differences in the vision of detail
Men have been found to have significantly greater sensitivity to details and fast-moving stimuli than women. According to studies, humans would be better able to perceive changes in brightness in space. It seems that, in these differences of vision has testosterone expression plays an important role. In fact, differences in testosterone levels promote a very different organisation of neurons in the visual cortex in men and women. Suffice it to say that there are more receptors for testosterone in the cerebral cortex (the part of the brain that processes information from the senses) than there are in the regions of the brain associated with reproduction. Men have more testosterone receptors than women, especially in the visual region of the cerebral cortex, so it makes sense that a different number of receptors would cause differences in visual perception.
A curiosity
A possible anthropological explanation for these physiological differences leads back to the responsibility of the hunter-gatherers of the first nomadic tribes: the hunters, the men, had to be able to distinguish between predator and prey from a distance, on the other hand, the women may have developed better vision at close range determined by the act of searching and gathering.
Sources
-Abramov et al. Biology of Sex Differences, 2012; 3 (1): 20 DOI: 10.1186/2042-6410-3-20
-Abramov et al. Biology of Sex Differences, 2012; 3 (1): 21 DOI: 10.1186/2042-6410-3-21
– Murray et al. J Vis. 2012 Jan 24;12(1).
Dr. Carmelo Chines
Direttore responsabile
English 
Italian