At the extremes of mental imagery vividness: a cognitive, neural and evolutionary investigation – IMAGINE

Close your eyes, and imagine yourself swimming in the sea..

In most people, the mental image of swimming in the sea is vivid with a high degree of detail.
Mental imagery is referred to as the simulation of a perceptual experience in the absence of a corresponding direct external stimulus and may occur across all sensory modalities. Mental imagery supports everyday human high-level cognitive processes such as spatial navigation, emotion, problem solving, memory recall and future thinking, and creativity.
Evolutionary psychology postulates that these high-level cognitive processes, integrating mental imagery, have deeply evolved during the hominid’s history; from Neanderthals, our closest relatives who disappeared about 30,000 years ago, to Homo Sapiens who is characterized by his unique creativity illustrated through technological innovations and figurative art, the latter being very limited in Neanderthals.

Surprisingly, recent reports have emerged of a minority of healthy adults for whom mental imagery is vague, if not completely absent. Over the past decade, there has been a growing interest in this intriguing congenital condition referred to as aphantasia which characterizes the self-reported inability to generate mental images associated with autobiographical memory and face recognition problems. On the opposite extreme of the imagery capacity spectrum, the hyperphantasia condition has also been recently proposed to refer to the other proportion of adults who self-reports a 'photo-like mental imagery’.

To date, the investigation of the cognitive mechanisms and neural circuits underlying mental imagery remains surprisingly limited. We will therefore develop innovative, reliable and objective markers of inter-individual differences in mental imagery capacities. Moreover, we will propose advanced non-invasive brain stimulation techniques, applied alone or combined with cognitive training, to modulate the activity of brain regions involved during mental imagery and thus increase the ability to imagine in adults with aphantasia.
Moreover, the hypothesis of a contribution of an archaic genetic inheritance on our (in)capacity to generate mental imagery has never been proposed and tested. Since it is now possible to quantify Neanderthal admixture in modern human genomes -a recent milestone achievement- we will test the if there is a link between extreme individual differences in mental imagery vividness (from aphantasia to hyperphantasia) and the proportion of Neanderthal-derived genetic variation (from high to low) in present-day people.

By addressing these questions, the IMAGINE project will offer exciting new insights into the functioning, complexity and evolution of human cognition.