Conceptual distinctiveness supports detailed visual long-term memory for real-world objects.

Abstract

Humans have a massive capacity to store detailed information in visual long-term memory. The present studies explored the fidelity of these visual long-term memory representations and examined how conceptual and perceptual features of object categories support this capacity. Observers viewed 2,800 object images with a different number of exemplars presented from each category. At test, observers indicated which of 2 exemplars they had previously studied. Memory performance was high and remained quite high (82% accuracy) with 16 exemplars from a category in memory, demonstrating a large memory capacity for object exemplars. However, memory performance decreased as more exemplars were held in memory, implying systematic categorical interference. Object categories with conceptually distinctive exemplars showed less interference in memory as the number of exemplars increased. Interference in memory was not predicted by the perceptual distinctiveness of exemplars from an object category, though these perceptual measures predicted visual search rates for an object target among exemplars. These data provide evidence that observers’ capacity to remember visual information in long-term memory depends more on conceptual structure than perceptual distinctiveness.

What makes an image memorable?

“…Mean saturation and value, on the other hand, as well as the first three moments of the pixel intensity histogram, exhibited weaker correlations with memorability ( Figure 5). These findings concord with other work that has shown that perceptual features are not retained in long term visual memory [11]. In order to make useful predictions, more descriptive features are likely necessary.…”

“…This is not surprising given the large role that semantics play in picture memory [13,11]. To investigate the role of object semantics, we performed the same regression as above, except this time using the entire joint (object class, statistic) distributions as features.…”

“…The reasons why some images are remembered are varied; some pictures might contain friends, a fun event involving family members, or a particular moment during a trip. Other images might not contain any recognizable monuments or people and yet also be highly memorable [1,12,11,19]. In this paper we are interested in this latter group of pictures: what are the intrinsic image features that may make an image memorable?…”

Parallel interactive retrieval of item and associative information from event memory

“…Stimuli consisted of indoor and outdoor scene images derived from two image sets (Goh et al, 2004;Konkle et al, 2010). The images were first screened to remove any legible writing (to preclude this as a strategy to remember particular images) as well as people (since these were particularly salient relative to other scene content).…”

Cortical pattern separation and item-specific memory encoding

“…Twelve participants rated the perceptual similarity of items within each pair from 1 (highly similar) to 5 (highly distinctive), and 11 rated intra-pair conceptual similarity on the same scale. Participants were asked to base perceptual similarity judgements on visual features such as shape or colour, and to base conceptual similarity judgements on how well the images corresponded to the same kind of object, i.e., two mountain bikes would be judged as conceptually similar, whereas a collie and bulldog, although both belonging to the basic-level category 'dog' should be rated less conceptually similar (Konkle et al, 2010). Image pairs were presented until 800 ms after a response was made, up to a maximum presentation time of 6000 ms.…”