A systematic review and meta-analysis were conducted to synthesize the existing literature on how transcranial magnetic stimulation (TMS) has been used to modulate episodic memory. Given the numerous parameters of TMS protocols and experimental design characteristics that can be manipulated, a mechanistic understanding of how changes in the combination of parameters (e.g., frequency, timing, intensity, targeted brain region, memory task) modulate episodic memory is needed. To address this, we reviewed 59 studies and conducted a meta-analysis on 245 effect sizes from 37 articles on healthy younger adults ( N = 1,061). Analyses revealed generally more beneficial effects of 1-Hz rTMS vs. other frequencies on episodic memory. Moderation analyses revealed complex interactions as online 20-Hz rTMS protocols led to negative effects, while offline 20-Hz rTMS led to enhancing effects. There was also an interaction between stimulation intensity and frequency as 20-Hz rTMS had more negative effects when applied below- vs. at-motor threshold. Conversely, 1-Hz rTMS had more beneficial effects than other frequencies when applied below- vs. at- or above-motor threshold. No reliable aggregate or hypothesized interactions were found when assessing stimulation site (frontal vs. parietal cortex, left vs. right hemisphere), stimulated memory process (during encoding vs. retrieval), the type of retrieval (associative/recollection vs. item/familiarity), or the type of control comparison (active vs. sham or no TMS) on episodic memory. However, there is insufficient data to make strong inference based on the lack of aggregate or two-way interactions between these factors, or to assess more complex (e.g., 3-way) interactions. We reviewed the effects on other populations (healthy older adults and clinical populations), but systematic comparison of parameters was also prevented due to insufficient data. A database of parameters and effects sizes is available as an open source repository so that data from studies can be continuously accumulated in order to facilitate future meta-analysis. In conclusion, modulating episodic memory relies on complex interactions among the numerous moderator variables that can be manipulated. Therefore, rigorous, systematic comparisons need to be further investigated as the body of literature grows in order to fully understand the combination of parameters that lead to enhancing, detrimental or null effects on episodic memory.

Cognitive reappraisal is an emotion regulation strategy that involves reinterpreting the meaning of an event or its outcome to change its emotional trajectory. In this study, we examined how cognitive reappraisal affects both emotional experience and memory outcomes. We also examined whether these outcomes are modulated by participants’ self-reported success at generating reappraisals. To do this, we asked participants to use situation-focused reappraisals to decrease their emotional response to some negative images and to passively view other negative images while facial electromyography (EMG) was recorded. After each trial, participants rated the image’s emotional valence and arousal. During reappraisal trials, participants also self-reported their success in generating a reappraisal. One week later, memory was assessed with a surprise free recall test followed by a recognition test. Compared with images that were passively viewed, participants (N = 42) rated the successfully reappraised images as lower in arousal and less negative in valence. Meanwhile, there was an emotional cost associated with failures to generate reappraisals; participants rated these images as higher in arousal and more negative in valence. No similar effects emerged for the EMG ratings. In contrast to these emotional outcomes, a different pattern emerged for the memory outcomes. Instructions to reappraise led to enhanced recall and recognition and to greater memory confidence regardless of whether or not participants successfully generated the reappraisals. Taken together, these results suggest that trying, but failing, to generate a situation-focused cognitive reappraisal may be detrimental. In these situations, people feel worse but remember the situation well.

Our findings show that the positivity effect is more robust when testing situations minimize stereotype threat. They also suggest that health interventions designed to capitalize on the positivity effect should ensure that ageist stereotypes are mitigated in the environment.

Previous research points to an association between retrieval-related activity in the medial prefrontal cortex (mPFC) and preservation of emotional information compared with co-occurring neutral information following sleep. Although the role of the mPFC in emotional memory likely begins at encoding, little research has examined how mPFC activity during encoding interacts with consolidation processes to enhance emotional memory. This issue was addressed in the present study using transcranial magnetic stimulation in conjunction with an emotional memory paradigm. Healthy young adults encoded negative and neutral scenes while undergoing concurrent TMS with a modified short intermittent theta burst stimulation (sTBS) protocol. Participants received stimulation to either the mPFC or an active control site (motor cortex) during the encoding phase. Recognition memory for scene components (objects and backgrounds) was assessed after a short delay (30 min) and a long delay [24 h (including a night of sleep)] to obtain measures of specific and gist-based memory processes. The results demonstrated that, relative to control stimulation, sTBS to the mPFC enhanced memory for negative objects on the long delay test (collapsed across specific and gist-based memory measures). mPFC stimulation had no discernable effect on memory for objects on the short delay test nor on the background images at either test. These results suggest that mPFC activity occurring during encoding interacts with consolidation processes to preferentially preserve negatively salient information.

Previous research has shown that neural activity elicited by informative prestimulus cues during encoding differ with respect to subsequent memory outcomes. These findings have been taken as evidence that prestimulus cues benefit processes associated with successful encoding and, ultimately, subsequent memory performance. However, previous studies have not included the conditions necessary to appropriately test this assumption. We address this shortcoming by examining how informative and uninformative prestimulus encoding cues affect memory accuracy for upcoming stimuli compared to a no cue condition. At encoding, participants made one of two semantic judgments on words preceded by an informative prestimulus cue that identified the upcoming semantic judgment, an uninformative prestimulus cue that signaled an upcoming trial but no information about the semantic judgment, or no cue. Dual process estimates of familiarity, but not recollection, demonstrated a graded pattern with the informativeness of the prestimulus cues (i.e., informative > uninformative > no cues). Moreover, both informative and uninformative prestimulus cues enhanced subsequent source memory accuracy for the encoding task compared to the no cue condition. These findings suggest that prestimulus cues can strengthen the processes that support successful memory encoding and benefit subsequent familiarity and source memory.