Dissociation in Autism Between Reading Gaze Direction Versus Mental States From the Eyes

Background: Autism Spectrum Conditions (ASC) are characterized by social and communication difficulties. These include abnormalities in gaze perception and in theory of mind (ToM), including reading other’s mental states from their eyes. There have been mixed findings in various tasks of gaze processing to date, with some showing intact ability in ASC and others showing deficits. They may be utilizing strengths in perceptual processing to understand some information from the eyes, however other information from the eyes requires higher-level metarepresentation that is deficient in ASC.

Objectives: To investigate for a dissociation between reading perceptual information about gaze direction versus mental state information from the eyes of others, in adults with and without ASC. Predictions: People with ASC would show deficits in reading mental states from the eyes, but the mechanisms for coding the gaze direction of others would be intact.

Methods: We tested 19 males with ASC, and 19 typical male controls matched for age, handedness, and IQ on two different tests requiring the processing of information from the eyes of others. Reading perceptual states from the eyes was tested using a paradigm where participants performed a baseline gaze perception task, then repeated the task after viewing extreme gaze directed 30 degrees to the left and then to the right. This task typically produces ‘gaze adaptation’ effects: individuals report that gaze involving small deviations from centre, and that is in the same direction as the extreme gaze, as being centre gaze. In contrast, small deviations of gaze in the opposite direction to the extreme examples are viewed accurately. Reading mental states from the eyes was tested using the ‘Reading the Mind in the Eyes’ Test, where people determine the mental and emotional states of others using information from the eyes.

Results: Both the control and ASC groups showed the typical gaze adaptation effects, for both the left and right directions. However, the ASC group showed deficits in reading the mind from the eyes compared to the control group.

Conclusions: These results show a dissociation in ASC involving intact reading of perceptual states about the gaze direction of other’s alongside deficits in reading mental states from the eyes. This suggests the neural mechanism coding for the gaze directions of others is intact in ASC. However, information from the eyes is not utilized successfully for higher-level abilities such as mental state attribution, which rely on different mechanisms than computing eye gaze direction.