Paper
Previous research using reverse correlation to explore the relationship between brain activity and presented image information found that Face Fusiform Area (FFA) activity could be related to the appearance of faces during free viewing of the Hollywood movie \"The Good, the Bad, and the Ugly\" (Hasson, et al, 2004). We applied this approach to the naturalistic viewing of unedited footage of city-centre closed-circuit television (CCTV) surveillance. Two 300 second videos were used, one containing prosocial activities and the other antisocial activities. Brain activity revealed through fMRI as well as eye movements were recorded while fifteen expert CCTV operators with a minimum of 6 months experience of CCTV surveillance alongside an age and gender matched control group of fifteen novice viewers were scanned while watching the videos. Independent scans functionally localized FFA and posterior Superior Temporal Sulcus (pSTS) activity using faces/houses and intact/scrambled point-light biological motion displays respectively. Reverse correlation revealed peaks in FFA and pSTS brain activity corresponding to the expert and novice eye movements directed towards faces and biological motion across both videos. In contrast, troughs in activation corresponded to camera-induced motion when a clear view of visual targets were temporarily not available. Our findings, validated by the eye movement data, indicate that the predicted modulation of brain activity occurs as a result of salient features of faces and biological motion embedded within the naturalistic stimuli. The examination of expertise revealed that in both pSTS and FFA the novices had significantly more activated timeframes than the experienced observers for the prosocial video. However, no difference was found for the antisocial video. The modulation of brain activity, as well as the effect of expertise gives a novel insight into the underlying visual processes in an applied real-life task.
