Does long-term object priming depend on the explicit detection of object identity at encoding?

Abstract

It is currently unclear whether objects have to be explicitly identified at encoding for reliable behavioral long-term object priming to occur. We conducted two experiments that investigated long-term object and non-object priming using a selective-attention encoding manipulation that reduces explicit object identification. In Experiment 1, participants either counted dots flashed within an object picture (shallow encoding) or engaged in an animacy task (deep encoding) at study, whereas, at test, they performed an object-decision task. Priming, as measured by reaction times (RTs), was observed for both types of encoding, and was of equivalent magnitude. In Experiment 2, non-object priming (faster RTs for studied relative to unstudied non-objects) was also obtained under the same selective-attention encoding manipulation as in Experiment 1, and the magnitude of the priming effect was equivalent between experiments. In contrast, we observed a linear decrement in recognition memory accuracy across conditions (deep encoding of Experiment 1 > shallow encoding Experiment 1 > shallow encoding of Experiment 2), suggesting that priming was not contaminated by explicit memory strategies. We argue that our results are more consistent with the identification/production framework than the perceptual/conceptual distinction, and we conclude that priming of pictures largely ignored at encoding can be subserved by the automatic retrieval of two types of instances: one at the motor level and another at an object-decision level.

Can pupillometry distinguish accurate from inaccurate familiarity?

“…This should have effectively and considerably reduced differences in cognitive effort between contrasting T A B L E 1 Results from the multilevel logistic regression model predicting category membership (FA, CR) from pupillary response and BOLAR index predictors (Model 1), and the multilevel regression model predicting pupil dilation from BOLAR index and response category (Model 2) categories. Although we acknowledge that RT-matching may still be insufficient to perfectly match effort and familiarity strength between any two categories, changes in RTs remain a popular proxy for cognitive effort (Beatty, 1982;Gomes & Mayes, 2015a, 2015bMontefinese et al, 2013;Porter et al, 2007;Võ et al, 2008).…”

Inputs to prefrontal cortex support visual recognition in the aging brain

“…However, in terms of the priming task, as long as participants were consistent in how they named the item, even if they could not identify it visually, then the name they used was irrelevant. Recent research has demonstrated that long-term object priming does not depend on explicit detection of object identity during the encoding stage 35 . Importantly, all participants demonstrated significant implicit memory via repetition priming: i.e., repeated items in this context are more predictable, leading to a reduced reaction time, compared with novel items.…”

Priming for novel object associations: Neural differences from object item priming and equivalent forms of recognition

“…Importantly, the relational memory theory proposes that the hippocampus is involved in the processing and representation of relational information regardless of whether retrieval is made with or without conscious awareness. Long‐term repetition priming is a kind of stimulus‐specific memory for studied items, arguably independent of conscious awareness (e.g., Gomes and Mayes, ; Gomes et al, ), in which one or more exposures to a stimulus facilitate or bias performance in memory tasks that do not make reference to these previous encounters (e.g., Schacter, ; Richardson‐Klavehn and Bjork, ). Whereas single item priming is thought to involve mainly occipitofrontal structures (see Buckner and Koutstaal, ; Henson, for reviews) as well as the perirhinal cortex (PRC; e.g., Wang et al, ; Dew and Cabeza, ), there is an emerging body of evidence linking the hippocampus to the encoding and retrieval of associative unaware memories, where behavioral facilitation is shown when previously encountered pairs of unrelated items are repeated (see Hannula and Greene, for a review; but see Verfaelllie et al, ).…”