In these monkeys 80 per cent of the neuron cell cortex is multisensory phonetic and also responds to visual stimuli. Thus, all the information is integrated

It is known for some time that monkeys are able to integrate information in various ways to recognize monkeys in the group and their intentions, just like us and like many other other animals. What we did not know until today was how our "cousins" could associate verses and faces, optimising thus the process of individual recognition. The experiment helps to clarify that which was published in Journal of Neuroscience and was conducted by Aif Ghazanfar and collaborators at Princeton (USA) on a kind of macaco. The researchers found that, in these monkeys, many neurons are in fact multi-sensorial and respond differently depending on whether the hearing and visual stimuli are at the same time or not.

For monkeys, which live in social groups and must manage complex relationships - conflicting and friendly - it is crucial to combine auditory stimuli (leading information-type sound, as a sound threat) and images (which provide summary information, such as the color of skin or facial features).

The group Ghazanfar could shed light on the mechanism of integration of different stimuli by measuring the activity of visual and auditory cortex areas of the brain, respectively, for image and sound. Measurements were made under different conditions: in one case the animals could both see fellow companions in the group, listen to their sounds, while in other cases the animals could alternatively listen to the auditory component only or see the companions (only visual component).