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Fast and automatic behavioral responses are required to avoid collision with an approaching stimulus. Accordingly looming stimuli have been found to be highly salient and efficient attractors of attention due to the implication of potential collision and potential threat. Here we address the question of whether looming motion is processed in the absence of any functional primary visual cortex and consequently without awareness. For this we investigated a patient (TN) suffering from complete bilateral damage to his primary visual cortex. Using an fMRI paradigm we measured TN’s brain activation during the presentation of looming receding rotating and static point lights of which he was unaware. When contrasted with other conditions looming was found to produce bilateral activation of the middle temporal areas as well the superior temporal sulcus and inferior parietal lobe. The latter are generally thought to be involved in multisensory processing of motion in extrapersonal space as well as attentional capture and saliency. No activity was found close to the lesioned V1 area. This demonstrates that looming motion is processed in the absence of awareness through direct subcortical projections to areas involved in multisensory processing of motion and saliency that bypass V1.

Visual adaptation is a powerful tool to probe the short-term plasticity of the visual system. Adapting to local features such as the oriented lines can distort our judgment of subsequently presented lines, the tilt aftereffect. The tilt aftereffect is believed to be processed at the low-level of the visual cortex, such as V1. Adaptation to faces, on the other hand, can produce significant aftereffects in high-level traits such as identity, expression, and ethnicity. However, whether face adaptation necessitate awareness of face features is debatable. In the current study, we investigated whether facial expression aftereffects (FEAE) can be generated by partially visible faces. We first generated partially visible faces using the bubbles technique, in which the face was seen through randomly positioned circular apertures, and selected the bubbled faces for which the subjects were unable to identify happy or sad expressions. When the subjects adapted to static displays of these partial faces, no significant FEAE was found. However, when the subjects adapted to a dynamic video display of a series of different partial faces, a significant FEAE was observed. In both conditions, subjects could not identify facial expression in the individual adapting faces. These results suggest that our visual system is able to integrate unrecognizable partial faces over a short period of time and that the integrated percept affects our judgment on subsequently presented faces. We conclude that FEAE can be generated by partial face with little facial expression cues, implying that our cognitive system fills-in the missing parts during adaptation, or the subcortical structures are activated by the bubbled faces without conscious recognition of emotion during adaptation. Published version