Poster D102, Monday, March 26, 8:00-10:00 am, Exhibit Hall C
The Genesis of Visual Memory through Strong Perceptual Representations: Tracking the Spatio-Temporal Neural Trace of Memorability
Caitlin Mullin1, Yalda Mohsenzadeh1, Dimitrios Pantazis1, Aude Oliva1; 1MIT
Not all images are perceived equally — some have a higher likelihood of sticking in your mind. How does the brain process these images compared to those that fade into oblivion? Here we test the hypothesis that more memorable images show a greater neural perceptual trace (robust and sustained brain signals) than those that are less memorable. In order to access both high spatial and temporal neural signals, we employed the novel approach of fusing MEG and fMRI data (Cichy et al., 2014; 2016) using representational similarity analysis (Kriegeskorte et al., 2008). From the LaMem Memorability image set (Khosla et al., 2015), we constructed a subset of more and less memorable images balanced for both low-level image statistics and high-level semantic categories (faces, objects, scenes, animates). Results revealed that more memorable images recruited the medial and lateral regions of the occipito-temporal processing stream to a greater degree than the less memorable images. By 100ms after image onset, we find a more robust representation for high memorable images in the fusiform gyrus, lateral occipital and parahippocampal cortices. In addition, the neural representations of memorable images were more sustained in time both during (online perception) and after (iconic memory) image presentation. This robust and sustained representation found in high level brain regions for more memorable images could point to the perceptual maintenance required to encourage the system to encode the information into long term memory.
Topic Area: PERCEPTION & ACTION: Vision