Prime time news: the influence of primed positive and negative emotion on susceptibility to false memories

The effect of image category and incidental arousal on boundary restriction

People's memory for scenes has consequences, including for eyewitness testimony. Negative scenes may lead to a particular memory error, where narrowed scene boundaries lead people to recall being closer to a scene than they were. But boundary restriction-including attenuation of the opposite phenomenon boundary extension-has been difficult to replicate, perhaps because heightened arousal accompanying negative scenes, rather than negative valence itself, drives the effect. Indeed, in Green et al. (2019) arousal alone, conditioned to a particular neutral image category, increased boundary restriction for images in that category. But systematic differences between image categories may have driven these results, irrespective of arousal. Here, we clarify whether boundary restriction stems from the external arousal stimulus or image category differences. Presenting one image category (everyday-objects), half accompanied by arousal (Experiment 1), and presenting both neutral image categories (everyday-objects, nature), without arousal (Experiment 2), resulted in no difference in boundary judgement errors. These findings suggest that image features-including inherent valence, arousal, and complexity-are not sufficient to induce boundary restriction or reduce boundary extension for neutral images, perhaps explaining why boundary restriction is inconsistently demonstrated in the lab.

A systematic review of the relationship between emotion and susceptibility to misinformation

Inaccurate memory reports can have serious consequences within forensic and clinical settings, where emotion and misinformation are two common sources of memory distortion. Many studies have investigated how these factors are related; does emotion protect memory or leave it more vulnerable to the distorting effects of misinformation? The findings remain diffused. Thus, the present review aimed to clarify the relationship between emotion and susceptibility to misinformation. 39 eligible studies were reviewed. Results varied according to the type and dimension of emotion measured. Level of arousal may be unrelated to susceptibility to misinformation when retrieval occurs without delay; studies including delayed retrieval were limited. Stimuli valence may be associated with increased susceptibility to peripheral misinformation but unrelated to other misinformation. The following results were reported by limited studies: short-term distress and moderate levels of stress may decrease susceptibility, while anger and greater cortisol response to stress may increase susceptibility to misinformation. Source memory may also be unaffected by emotion. The results have important potential implications for forensic and clinical practice, for example by highlighting the value of enquiring witnesses' source memory. Methodological recommendations for future studies are made.

The role of arousal in boundary judgement errors

Eyewitnesses to a crime rely heavily on their visual memory; however, there are many ways that the details of visual scenes can be missed, or distorted. In particular, for emotional scenes, the "boundaries" are narrowed at retrieval, whereas central details-such as a weapon-are remembered in greater detail. This phenomenon is known as boundary restriction, the reverse of boundary extension whereby people tend to expand the boundaries of a neutral scene at retrieval. In the present series of experiments, we investigated whether arousal is the element of an emotional scene that leads to increased boundary restriction or reduced boundary extension. We presented neutral images to participants either with or without a stress-inducing noise. In Experiment 1a and 1b, at test, participants viewed the image they originally viewed next to the same image but with narrower or wider boundaries and selected which of the two images they originally viewed. In Experiment 2, at test, participants viewed the identical image they originally viewed, but were told the boundaries had been changed. Participants selected the extent to which the images at test had restricted or extended boundaries compared to their memory of the original image. When the noise stressor was present, participants made more boundary restriction errors-selecting the image with narrower boundaries than the original-and fewer boundary extension errors than when the noise was absent. Our data suggest that arousal plays a key role in boundary judgements.

Emotionally negative pictures enhance gist memory

In prior work on how true and false memory are influenced by emotion, valence and arousal have often been conflated. Thus, it is difficult to say which specific effects are caused by valence and which are caused by arousal. In the present research, we used a picture-memory paradigm that allowed emotional valence to be manipulated with arousal held constant. Negatively valenced pictures elevated both true and false memory, relative to positive and neutral pictures. Conjoint recognition modeling revealed that negative valence (a) reduced erroneous suppression of true memories and (b) increased the familiarity of the semantic content of both true and false memories. Overall, negative valence impaired the verbatim side of episodic memory but enhanced the gist side, and these effects persisted even after a week-long delay. (PsycINFO Database Record