When communicating with multiple others, it is vital to understand the approximate number of people with a particular facial expression when assessing a situation. A previous study of numerosity estimations for emotional faces observed lower accuracy and underestimations for angry faces compared to neutral faces (Baker, Rodzon, & Jordan, 2013). However, the task used in this study was a simple enumeration for an identical face image (i.e., same individual and expression); a situation that does not usually occur in real life. Moreover, the previous research only considered angry faces, but different facial expressions have specific functions. Accordingly, the present study focuses on sad expressions, which convey losses and elicit empathy and prosocial behavior from others, to investigate their effects on enumeration. The participants’ task was to enumerate only certain facial expressions, from among combinations of smiling and neutral or sad and neutral faces, which were displayed for 500 milliseconds. When multiple targets were presented, accuracy for sad faces was lower compared to smiling faces and counts were underestimated. These results suggest that faces with sad emotions hinder enumeration when briefly presented.

The pronounceability of visually-presented words has been suggested to influence the retention of words. However, it remains unclear as to whether pronounceability affects the encoding process of visually-presented words or whether it only influences subsequent process of memory retention. We investigated the recognition thresholds of tachistoscopically presented words. In Experiment 1, we classified words based on a prior study of word pronounceability and compare the recognition thresholds among easy-to-pronounce words, difficult-to-pronounce words, and non-words. In Experiment 2, we conducted a word naming task and classified words as easy-to-pronounce and difficult-to-pronounce based on speech duration of the words. In both experiments, no significant differences were observed in the recognition thresholds for easy-to-pronounce and difficult-to-pronounce words. These findings suggest that the recognition processing of visually-presented words is identical regardless of word pronounceability and that pronounceability may influence the subsequent process of memory retention. Moreover, we also investigate the possible application of a presentation-duration design for dynamic information.

Retrieval stopping refers to intentionally stopping the retrieval of memories, which has been investigated with the Think/No-Think (TNT) paradigm. In this article, after introducing the paradigm’s experimental procedure, we review the after-effects, mechanisms, modulatory factors of retrieval stopping. We also discuss the differences between retrieval stopping and thought suppression, highlighting the aspects of retrieval stopping that are critical to forgetting. Retrieval stopping not only induces the forgetting of target memories but it also influences various cognitive processes, including emotional responses that involve memory. It has been assumed that retrieval stopping entails domain-general reactive control functions that are involved in motor control and emotion regulation. However, the mechanisms that underlie forgetting by retrieval stopping remain unclear in contrast to those of retrieval stopping per se. Given the domain-general nature of its control mechanisms, a comprehensive understanding of retrieval stopping and its after-effects can contribute to elucidating the effects of motor control and emotion regulation, and eventually to yielding an integrative framework of cognitive control.

Remembering of episodic memory is characterized by autonoetic consciousness, which enables us to mentally re-experience the past events. It means that the system of episodic memory enables us to mentally travel into the temporally passed event. The orientation of mental time travel is not only for the past events, also for the future or counterfactual events. And then, the memory system could be interpreted as a system to recombine episodic details and construct events in various time frames. We introduce some research which is related to this memory system; episodic future thinking, details in autobiographical memory, cognitive offloading, intentional cognitive control and forgetting, and computational study on subjective meta-memory. Finally, we discuss the recent perspective of episodic memory or episodic sciences and future research directions.

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