Neural Correlates of Attentional Modulation on Encoding and Retrieval of Face-Scene Compound Images: An fMRI Study

Abstract

The well-known “butcher-on-the-bus” effect has been interpreted to indicate automatic binding between a face and the context against which it was seen despite little or no intention to combine them. Here we examined the extent to which binding between faces and scenes can be affected by orienting attention. During encoding, participants were presented with face-scene compound images and asked to orient their attention to either the faces and rate their personality traits, or to scenes and rate their semantic attributes. During recognition, they were shown faces or scenes alone and judged whether they had encountered them during encoding. Brain images during encoding and retrieval were collected via an fMRI scanner. For both faces and scenes, decrement in recognition due to attentional orientation was evident, where participants were more accurate in recognizing the faces and scenes to which they oriented attention during encoding than those they didn’t. Whole-brain and ROI analyses were conducted to uncover neural correlates of attentional modulation. During encoding, results showed significant activations of the right hippocampus (HPC) and right and left retrosplenial cortex (RSC) with respect to encoding success activity (i.e., hit–miss) when orienting attention to faces. Furthermore, ROI analyses revealed that orienting attention to scenes led to higher activations in both the right and left occipital place area (OPA), the left RSC, and the right HPC. During retrieval, the left HPC and medial PFC in both hemispheres were highly activated when orienting attention to faces with respect to retrieval success activity. Moreover, the right and left RSC, right posterior superior temporal sulcus (pSTS), and the right anterior cingulate cortex (rACC) were highly activated with respect to RSA when orienting attention to scenes. Taken together, these findings reveal differential brain mechanisms underlying the effects of attentional modulation on the encoding and retrieval of faces and scenes.