Sharon Gilaie-Dotan¹, Reout Dayan¹, Olga Kreichman¹; ¹Bar-Ilan University

Although studies show that human visual memory for object images is phenomenal during active engaging encoding, it is still unclear if this reflects memory during naturalistic visual behavior. Recent studies show that during naturalistic encoding, image memory is much poorer than the levels reported earlier and that the knowledge that an image was not seen before is much higher than recognition memory for already-seen images. Here in a set of comprehensive experiments (n=249) we parametrically examined whether during more naturalistic-like encoding, memory for object images is robust or susceptible to multiple factors. Earlier results with face, people, indoor and outdoor images were first replicated with object images. In addition, we found that during these less engaging encoding conditions people's memory was adversely affected by the number of encoded images and by the number of novel (distractor) images the previously seen image was tested amongst (from best performance of ~90% memory in a 2AFC task for 60 encoded images down to ~50% memory in a 6AFC task for 180 encoded images). While human capacity for remembering new images can reach outstanding levels during highly engaging conditions, our results indicate that during more naturalistic-like conditions, image memory is much weaker and susceptible to multiple influences. We assume that our findings overestimate everyday visual memory capacity and that much less of the novel information we come across everyday actually registers in memory.

Acknowledgements: This study was funded by ISF Individual Research Grants 1485/18 and 1462/23 to SGD, and by CHE Lev-Zion Scholarship to OK.