Should you Sleep on it? The Effects of Overnight Sleep on Subjective Preference‐based Choice

Conventional wisdom and studies of unconscious processing suggest that sleeping on a choice may improve decision making. Although sleep has been shown to benefit several cognitive tasks, including problem solving, its impact on everyday choices remains unclear. Here we explore the effects of ‘sleeping on it’ on preference‐based decisions among multiple options. In two studies, individuals viewed several attributes describing a set of items and were asked to select their preferred item after a 12‐hour interval that either contained sleep or was spent fully awake. After an overnight period including sleep, individuals showed increases in positive perceptions of the choice set. This finding contrasts with previous research showing that sleep selectively enhances recall for negative information. In addition, this increase in positive recall did not translate into a greater desire to purchase their preferred item or into an overall benefit for choice satisfaction. Time‐of‐day controls were used to confirm that the observed effects could not be explained by circadian influences. Thus, we show that people may feel more positive about the choice options but not more confident about the choice after ‘sleeping on’ a subjective decision. We discuss how the valence of recalled choice set information may be important in understanding the effects of sleep on multi‐attribute decision making and suggest several avenues for future research. Copyright © 2015 John Wiley & Sons, Ltd.     

Successfully controlling intrusive memories is harder when control must be sustained

After unpleasant events, people often experience intrusive memories that undermine their peace of mind. In response, they often suppress these unwanted memories from awareness. Such efforts may fail, however, when inhibitory control demands are high due to the need to sustain control, or when fatigue compromises inhibitory capacity. Here we examined how sustained inhibitory demand affected intrusive memories in the Think/No-Think paradigm. To isolate intrusions, participants reported, trial-by-trial, whether their preceding attempt to suppress retrieval had triggered retrieval of the memory they intended to suppress. Such counter-intentional retrievals provide a laboratory model of the sort of involuntary retrieval that may underlie intrusive memories. Using this method, we found that longer duration trials increased the probability of an intrusion. Moreover, on later No-Think trials, control over intrusions suddenly declined, with longer trial durations triggering more relapses of items that had been previously been purged. Thus, the challenges of controlling retrieval appear to cause a decline in control over time, due to a change in state, such as fatigue. These findings raise the possibility that characteristics often true of people with psychiatric disorders – such as compromised sleep, and increased demand on control – may contribute to difficulties in suppressing intrusive memories.     

Impact of age-relevant goals on future thinking in younger and older adults

This study investigated how personal goals influence age differences in episodic future thinking. Research suggests that personal goals change with age and like autobiographical memory, future thinking is thought to be organised and impacted by personal goals. It was hypothesised that cueing older adults with age-relevant goals should modulate age differences in episodic details and may also influence phenomenological characteristics of imagined scenarios. Healthy younger and older adults completed the Future Thinking Interview [Addis, D. R., Wong, A. T., & Schacter, D. L. (2008). Age-related changes in the episodic simulation of future events. Psychological Science, 19(1), 33–41. doi:10.1111/j.1467-9280.2008.02043.x] adapted to activate age-appropriate goals. Narratives were scored with an established protocol to obtain objective measures of episodic and semantic details. Subjective features such as emotionality and personal significance showed age differences as a function of goal domain while other features (e.g., vividness) were unaffected. However, consistent with prior reports, older adults produced fewer episodic details than younger adults and this was not modulated by goal domain. The results do not indicate that goal activation affects level of episodic detail. With respect to phenomenological aspects of future thinking, however, younger adults show more sensitivity to goal activation, compared with older adults.     

Inconsistent-handed advantage in episodic memory extends to paragraph-level materials

Past research using handedness as a proxy for functional access to the right hemisphere demonstrates that individuals who are mixed/inconsistently handed outperform strong/consistently handed individuals when performing episodic recall tasks. However, research has generally been restricted to stimuli presented in a list format. In the present paper, we present two studies in which participants were presented with paragraph-level material and then asked to recall material from the passages. The first study was based on a classic study looking at retroactive interference with prose materials. The second was modelled on a classic experiment looking at perspective taking and the content of memory. In both studies, the classic effects were replicated and the general finding that mixed/inconsistent-handers outperform strong/consistent-handers was replicated. This suggests that considering degree of handedness may be an empirically useful means of reducing error variance in paradigms looking at memory for prose level material.     

Usage of semantic representations in recognition memory

Meanings of words facilitate false acceptance as well as correct rejection of lures in recognition memory tests, depending on the experimental context. This suggests that semantic representations are both directly and indirectly (i.e., mediated by perceptual representations) used in remembering. Studies using memory conjunction errors (MCEs) paradigms, in which the lures consist of component parts of studied words, have reported semantic facilitation of rejection of the lures. However, attending to components of the lures could potentially cause this. Therefore, we investigated whether semantic overlap of lures facilitates MCEs using Japanese Kanji words in which a whole-word image is more concerned in reading. Experiments demonstrated semantic facilitation of MCEs in a delayed recognition test (Experiment 1), and in immediate recognition tests in which participants were prevented from using phonological or orthographic representations (Experiment 2), and the salient effect on individuals with high semantic memory capacities (Experiment 3). Additionally, analysis of the receiver operating characteristic suggested that this effect is attributed to familiarity-based memory judgement and phantom recollection. These findings indicate that semantic representations can be directly used in remembering, even when perceptual representations of studied words are available.     

Narcissism,self-esteem,and the phenomenology of autobiographical memories

Across two studies, we investigated the influence of narcissism and self-esteem along with gender on phenomenological ratings across the four subscales of the Autobiographical Memory Questionnaire (AMQ; impact, recollection, rehearsal, and belief). Memory cues varied in valence (positive vs. negative) and agency (agentic vs. communal). In Study 2, we used different memory cues reflecting these four Valence by Agency conditions and additionally investigated retrieval times for the autobiographical memories (AMs). Results were consistent with the agency model of narcissism [Campbell, W. K., Brunell, A. B., & Finkel, E. J. (2006). Narcissism, interpersonal self-regulation, and romantic relationships: An agency model approach. In E. J. Finkel & K. D. Vohs (Eds.), Self and relationships: Connecting intrapersonal and interpersonal processes. New York, NY: Guilford], which characterises narcissists as being more concerned with agentic (self-focused) rather than communal (other-focused) positive self-relevant information. Narcissism predicted greater phenomenology across the four subscales for the positive-agentic memories (Study 1: clever; Study 2: attractive, talented) as well as faster memory retrieval times. Narcissism also predicted greater recollection and faster retrieval times for the negative-communal AMs (Study 1: rude; Study 2: annoying, dishonest). In contrast, self-esteem predicted greater phenomenology and faster retrieval times for the positive-communal AMs (Study 1: cooperative; Study 2: romantic, sympathetic). In both studies, results of LIWC analyses further differentiated between narcissism and self-esteem in the content (word usage) of the AMs.     

Reduced effects of pictorial distinctiveness on false memory following dynamic visual noise

High levels of false recognition for non-presented items typically occur following exposure to lists of associated words. These false recognition effects can be reduced by making the studied items more distinctive by the presentation of pictures during encoding. One explanation of this is that during recognition, participants expect or attempt to retrieve distinctive pictorial information in order to evaluate the study status of the test item. If this involves the retrieval and use of visual imagery, then interfering with imagery processing should reduce the effectiveness of pictorial information in false memory reduction. In the current experiment, visual-imagery processing was disrupted at retrieval by the use of dynamic visual noise (DVN). It was found that effects of DVN dissociated true from false memory. Memory for studied words was not influenced by the presence of an interfering noise field. However, false memory was increased and the effects of picture-induced distinctiveness was eliminated. DVN also increased false recollection and remember responses to unstudied items.     

An attention account of neural priming

Repetition priming of familiar stimuli (e.g., objects) produces a decrease in visual cortical activity for repeated versus novel items, which has been attributed to more fluent processing for repeated items. By contrast, priming of unfamiliar stimuli (e.g., abstract shapes) produces an increase in visual cortical activity. The mechanism for priming-related increases in activity for repeated unfamiliar stimuli is unknown. We hypothesised that such increases in activity may reflect attentional allocation to these items. We tested this hypothesis using a priming-spatial attention paradigm. During Phase 1 of Experiment 1, participants viewed unfamiliar abstract shapes and familiar objects. During Phase 2, participants identified target letters (S or H). Each target letter was preceded by a non-informative shape or object cue that was repeated (from Phase 1) or novel in the same (valid) or opposite (invalid) hemifield. In Experiment 2, we manipulated shape familiarity by presenting shapes once or six times during Phase 1. For both experiments, at valid locations, target identification accuracy was higher following repeated versus novel unfamiliar item cues and lower following repeated versus novel familiar item cues. These findings support our hypothesis that priming-related increases in visual cortical activity for repeated unfamiliar items may, in part, reflect attentional allocation.     

Does a person selectively recall the good or the bad from their personal past? It depends on the recall target and the person’s favourability of self-views

In three studies, participants remembered real-life behaviours at Time 1 and attempted to recall them at Time 2. When the recall target was the self, a positivity bias emerged: self-positivity. In Study 3, self-positivity extended to an individual (target) who was liked by the participant, but did it not extend to a disliked target. For this latter target, a negativity bias emerged. For recall targets that were participants’ acquaintances, self-positivity in recall was also eliminated in Studies 1 and 3, and a negativity bias in recall emerged in Study 2. Finally, in Study 2 (but not Study 3), the favourability of participants’ self-view predicted the magnitude of the self-positivity in self-recall, but it did not predict valence effects in other-recall. Taken together, the results indicate that the link between behaviour valence and recall is moderated by the recall target and the favourability of one’s self-view.