Theory of mind: the eyes have it

Abstract

‘You have that look in your eyes’. Some of us have heard such an accusation many times. The speaker, of course, wants it to be known that he or she understands just what our intentions are, based on some ocular characteristics. Furthermore, when we hear such a statement from a friend or someone who knows us well, there is a good chance they're right. An interpretation of gaze (especially of its direction) is a key aspect of many contemporary theories of mental-state attribution, most notably accounts based on Theory of Mind (ToM). An ability, or desire, to interpret and reciprocate gaze is often lacking in children with autism, for example, and in others who fail ToM tests. Using functional imaging, brain regions involved in the ToM task have been identified with relatively high reliability and, more interestingly, have shown some overlap in the left posterior superior temporal sulcus (STS) with a purely gaze-related task. That is, there has been some reason to suspect that, both psychologically and neurophysiologically, estimations of gaze behavior are related to the ToM concept and an understanding of the minds of other people.Andrew Calder and colleagues [1xReading the mind from eye gaze. Calder, A.J. et al. Neuropsychologia. 2002; 40: 1129–1138Crossref | PubMedSee all References[1] have found data that further support this notion. Experimental participants viewed photographs of models that varied in the direction of their gaze. The models were photographed looking directly at the camera, with gaze horizontally averted, vertically averted, or with their eyes closed. The task of the participants was incidental to the gaze conditions; they were asked to make judgments about the eyebrows of the faces in the photographs. Along with findings of increased sub-cortical signals and greater activation in the fusiform gyrus during direct gaze, the results confirmed, consistent with earlier work, that the STS was involved in this process. Calder et al. also found, however, that ‘more anterior regions of the superior and middle temporal gyri’ showed relatively high activation. Perhaps most significantly, the medial prefrontal (MPF) cortex appeared to be maximally engaged in the processing of horizontally averted gaze. The authors suggest that this structure could be involved in the attribution of the model's attention to some aspect of the environment, presumably based on a computation of the looking-direction. The MPF cortex is, then, another area indicated as part of the system responsible for the attribution of mental states and intentionality. This represents an important confirmation of the apparent correspondence between involved brain structures and at least one of the mechanisms of a ToM system. As such, we have more reason to believe that conclusions about the possession of mental states really can be drawn from that look in your eyes.