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Background: Mental time travel (MTT) is the ability to re-experience past events (autobiographic memory, AM) and pre-experience possible future events (episodic future thinking, EFT) through mental simulation. Empirical findings suggest that individuals with high level of schizotypy exhibit MTT impairment. However, the neural correlates of this impairment remain unclear., Method: Thirty-eight individuals with high level of schizotypy and 35 low level of schizotypy were recruited to complete an MTT imaging paradigm. Participants were required to recall past events (AM condition), imagine possible future events (EFT condition) related to cue words, or generate exemplars related to category words (control condition) while undergoing functional Magnetic Resonance Imaging (fMRI)., Results: AM showed greater activation in precuneus, bilateral posterior cingulate cortex, thalamus, and middle frontal gyrus than EFT. Individuals with high level of schizotypy exhibited reduced activation in the left anterior cingulate cortex during AM (vs. Control) and in the medial frontal gyrus during EFT (vs. Control) compared to individuals with low level of schizotypy. Although psychophysiological interaction analyses did not show any significant group difference, individuals with high level of schizotypy exhibited functional connectivity between left anterior cingulate cortex (seed) and right thalamus, between medial frontal gyrus (seed) and left cerebellum during MTT, whereas individuals with low level of schizotypy did not exhibit these functional connectivities., Conclusion: These findings suggest that decreased brain activations may underlie MTT deficits in individuals with high level of schizotypy., Competing Interests: Declaration of Competing Interest None., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Objective: This study aimed to examine prospective memory (PM) performance and the potential effect of implementation intention on PM performance and the underlying mechanisms in individuals with high schizotypyal traits (HSTs) using eye-tracking paradigms., Methods: In Experiment 1, 30 individuals with HSTs and 30 individuals with low schizotypal traits (LSTs) underwent a visual search task that involved PM cues, and participants' eye movements were recorded. In Experiment 2, 50 individuals with HSTs were randomly assigned to the implementation intention group and typical instruction group., Results: In Experiment 1, individuals with HSTs had a lower PM accuracy and performed less PM cue monitoring (indicated by fewer total fixation counts on distractor words) than individuals with LSTs. In Experiment 2, implementation intention significantly improved PM accuracy and increased total fixation counts on distractor words in individuals with HSTs compared to the HST group with typical instruction., Conclusions: Individuals with HSTs were impaired in PM and showed reduced cue monitoring compared to individuals with LSTs. Implementation intention improved PM performance and facilitated cue monitoring in individuals with HSTs., Significance: Our findings indicate that cue monitoring may be an important process of intervention target for PM for individuals in the schizophrenia spectrum., (Copyright © 2022 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

The Prospective and Retrospective Memory Questionnaire (PRMQ) is a widely-used questionnaire for evaluating individuals' memory failures in everyday life. However, whether the scale is valid for different age groups and gender, and how memory complaints change with age and gender remains less clear. This study aimed to validate the self-report PRMQ in a large Chinese sample across adolescence and adulthood and investigate age-related changes and gender differences in self-report prospective memory (PM) and retrospective memory (RM). A total of 2528 healthy individuals aged from 13 to 96 completed the Chinese version of the PRMQ. Results revealed that the PM-RM correlated factor model was the best fit model with satisfactory reliability and had measurement invariance across gender and adjacent age groups. Adolescents and adults reported similar memory complaints, while older people stated more memory difficulties. Female participants reported more PM errors than male participants, but this gender difference only showed in adolescents and adults. Taken together, these findings not only support the Chinese version of the PRMQ as a valid tool for evaluating prospective and retrospective memory difficulties across gender and adjacent age groups, but also reveal age-related changes and gender difference on self-report memory.

Prospective memory (PM) refers to the ability to remember to carry out a delayed intention in the future. Evidence suggests that emotionally salient cues can enhance PM functions in healthy population, but whether the benefit exists in schizophrenia and bipolar patients remains unclear. This study aimed to examine and compare the potential enhancement effect of emotional PM cues in schizophrenia patients and bipolar patients. Twenty-eight clinically stable schizophrenia participants, 26 euthymic bipolar participants and 29 controls completed a computerized PM task involving PM cues with different types of valences (i.e., positive, neutral and negative). All the three groups showed better PM performance when negative PM cues were presented compared with positive and neutral PM cues. The sizes of the enhancement effects of negative PM cues were large (all Cohen's d ≥ 1.00) and comparable across three groups. Our findings suggested that patients with schizophrenia and bipolar disorders could benefit from negative PM cues to an extent similar to healthy individuals, thus extended the notion of psychosis continuum to the important area of emotion-cognition interaction., (© 2021. Springer-Verlag GmbH, DE part of Springer Nature.)

Patients with schizophrenia (SCZ) consistently show prospective memory (PM) impairments, and the technique of implementation intentions has been shown to improve PM performance in these patients. PM is considered to have prospective and retrospective components. However, it remains unclear which component of PM is impaired in patients with SCZ and which component(s) is facilitated by implementation intentions (II). The present study aimed to examine these two issues. Forty-two patients with SCZ and 42 matched healthy controls were randomly assigned to an II group or a typical instruction group. All participants were administered a color-matching PM task. Results showed that, using a multinomial-modeling approach, patients with SCZ exhibited impairment in the retrospective component of PM. In addition, while II improved the prospective PM component in healthy controls, both prospective and retrospective PM components in patients with SCZ were improved. Together, our results shed light on the mechanism of PM impairment in SCZ patients and the mechanism of II in improving PM performance., Competing Interests: Declaration of competing interest None., (Copyright © 2019 Elsevier B.V. All rights reserved.)

We examined prospective memory (PM) function in children with attention deficit hyperactivity disorder (ADHD). A group of 28 children with ADHD and 28 typically developing children completed event-, time- and activity-based PM tasks and attention tests. ADHD children had impaired attention but intact PM performance. Both groups performed best in activity-based PM tasks, followed by event-based PM tasks, and performed worst in time-based PM tasks. ADHD children had lower ongoing task performance in the event-based PM task. The findings indicate that children with ADHD may have an intact PM, but this may be at the cost of ongoing task performance.

Aim: The present study aimed to explore the two-year naturalistic trajectory of time- and event-based prospective memory (PM) in patients with first-episode schizophrenia., Methods: We administered a computer-based dual-task PM paradigm to 57 individuals with first-episode schizophrenia at baseline and after 6 months, 12 months and 24 months. Forty-eight healthy controls were also recruited and completed all the measures at baseline. We compared the trajectories between time-based and event-based PM in first-episode schizophrenia patients using repeated measures ANOVAs, and examined the relationship between PM and clinical symptoms using Spearman's correlation., Results: PM impairments improved significantly after 24 months of follow-up. However, time-based and event-based PM appeared to run different trajectories. After 24 months, first-episode schizophrenia patient performed poorer than healthy controls in time-based but not event-based PM. PM did not appear to be correlated with clinical symptoms, both cross-sectionally and longitudinally., Conclusions: This is one of the longest follow-up studies investigating PM in first-episode schizophrenia. Our results provide evidence to support that time-based PM is more temporally stable than event-based PM., (© 2018 John Wiley & Sons Australia, Ltd.)

Prospective memory (PM) refers to the ability to remember to do something in the future. Implementation intention refers to a self-regulatory strategy in the form of "If …, then …" planning that can improve PM performance. However, the neural basis of the effect of implementation intention on PM remains unclear, as do the phases of PM that are affected by implementation intention. This study aimed to address these issues. Healthy participants were randomly assigned to the implementation intention (n = 18) and typical instruction (n = 20) conditions. All of them underwent functional magnetic resonance imaging (fMRI) scanning when performing a PM task, which differentiated encoding, maintenance, and execution phases. Results demonstrated that participants in the implementation intention group showed different brain activations compared to participants in the typical instruction group. During the encoding phase, the implementation intention group showed increased activations in the inferior frontal gyrus (BA 10) and supramarginal gyrus (BA 40) compared to the typical instruction group; during the maintenance phase, the typical instruction group showed stronger activations in the inferior frontal gyrus (BA 46) than the implementation intention group; during the execution phase, the typical instruction group showed increased activations in the precentral gyrus (BA 6) and middle frontal gyrus (BA 8) than the implementation intention group. These results demonstrated the neural correlates of implementation intention on PM in different phases, and support the conclusion of our previous review based on fMRI evidence that implementation intention's improvement of PM performance is not fully automatic., (© 2018 The Institute of Psychology, Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.)

Prospective memory (PM) is the ability to remember to carry out future intentions when prompted by a cue, and previous studies have suggested that emotional PM cues may enhance PM performance. This study examined the influence of emotional cues on PM performance in patients with schizophrenia and major depressive disorder. All participants were required to respond to emotional or neutral PM cues while completing a working memory task. Healthy participants showed improved PM performance with positive and negative cues. Patients with major depressive disorder were not impaired in PM performance and showed significant improvement in PM performance when cued by negative but not positive cues. Patients with schizophrenia had impaired PM performance irrespective of cue emotionality. In addition, the majority of patients with schizophrenia failed to show an emotional enhancement effect, and only those who had normal arousal ratings for negative PM cues showed emotional enhancement effect. These findings show for the first time that patients with schizophrenia exhibit PM impairments even with emotional cues, and suggest that arousal may be a critical factor for schizophrenia patients to utilize emotional cues to facilitate execution of future actions. In patients with major depressive disorder, our findings suggest that the negative bias in attention and retrospective memory may also extend to memory for future actions. These novel findings have both theoretical and clinical implications., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Objective: Prospective memory (PM) refers to the ability to remember to carry out intended actions after a delay. PM impairments are common in schizophrenia patients and are thought to be related to their prefrontal cortex dysfunction; however, this has not yet been examined directly in the research literature. The current study aimed to examine abnormalities in brain activation during PM task performance in schizophrenia patients., Method: Twenty-two schizophrenia patients and 25 matched healthy controls were scanned in a 3-T MRI machine while performing a PM task., Results: The results showed that compared to the healthy controls, schizophrenia patients performed significantly worse on the PM task. Furthermore, they exhibited decreased brain activation in frontal cortex including the right superior frontal gyri (Brodmann area 10), and other related brain areas like the anterior cingulate gyrus, parietal and temporal cortex, including precuneus, and some subcortext, including parahippocampal gyrus and putamen., Conclusions: These findings confirm the involvement and importance of the prefrontal cortex in PM and show evidence of hypofrontality in schizophrenia patients while performing a PM task., (PsycINFO Database Record (c) 2016 APA, all rights reserved.)

We comprehensively examined prospective memory (PM) performance in patients with obsessive-compulsive disorder (OCD), and explored the cognitive and psychopathological correlates of PM in this clinical population. Fifty-eight OCD patients and 58 healthy controls were assessed with computer-based PM tasks and related neurocognitive functions, and the participants also reported frequency of PM failures and compulsive behaviours in daily life. OCD patients had intact activity-based PM performance but had lower accuracy in time-based PM and longer reaction time to event-based PM cues compared to healthy controls. Among the neurocognitive functions, both the WCST (perseverative error) and the letter number span correlated with time-based PM. OCD patients reported similar number of PM failures in daily life as controls, which correlated with their intact event-based PM performance, suggesting a generally good insight into their PM functions. Neither clinician-assessed nor self-reported OCD symptoms correlated with PM performance. This study indicates that PM impairment tends to vary with the PM cue types in OCD patients. In addition, certain executive functions (i.e., mental shifting and updating) may contribute to time-based PM impairment in patients with OCD., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Background: Prospective memory (PM) deficits have been consistently found in people with schizophrenia. Although there is evidence to suggest that PM deficits may be putative markers for schizophrenia, no longitudinal study has investigated the persistence of PM deficits., Aims: We examined whether PM deficits persist after the onset of schizophrenia, and compared the trajectories of time- and event-based PM performance 12 months after illness onset. We also examined whether the association between PM and clinical symptoms changes over time 12 months after illness onset., Method: We recruited 58 individuals with first-episode schizophrenia for a 12-month follow-up study. Comparison participants were 37 healthy individuals who were matched in terms of demographics and intelligence with the patient group. PM functions and clinical symptoms were measured at baseline, the sixth month, and the twelfth month, using a computerized PM task and the Positive and Negative Syndrome Scale., Results: People with schizophrenia showed a gradual improvement in both time- and event-based PM 12 months after illness onset. However, compared to event-based PM, deficit in time-based PM persisted and was relatively stable. At baseline, PM functions were not associated with clinical symptoms. However, an association between time-based PM and PANSS positive and general symptoms emerged 12 months after the onset of schizophrenia., Conclusion: People with first-episode schizophrenia exhibit persistent time-based PM deficit. Our findings support that PM deficit, in particular, time-based deficit, may be a putative neuropsychological marker of schizophrenia., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Prospective memory (PM) is the ability to remember to carry out intended actions in the future. Empirical evidence suggests that PM deficits exist in individuals with chronic schizophrenia. However, it is unclear whether PM deficits in first-episode schizophrenia exist independently from other neuropsychological deficits. Moreover, prior research using patients with first-episode has been limited to small inpatient samples. We aimed to clarify the nature and extent of PM deficits in individuals with first-episode schizophrenia, using a large outpatient sample. Participants were 91 clinically stable outpatients with first-episode schizophrenia and 83 healthy controls. PM was assessed using both a subjective self-reported checklist and a laboratory-based task capturing time- and event-based PM. A battery assessing verbal and visuo-spatial working memory, as well as executive functions was also administered. ANOVA analyses showed that patients with first-episode schizophrenia performed significantly poorer than healthy controls in time- and event-based PM. Stepwise linear regression analyses suggested that cognitive flexibility predicted time- and event-based PM; and working memory predicted event-based PM. Subgroup analyses showed that "cognitive-preserved" patients with first-episode schizophrenia tended to perform poorer in time-based PM deficit than healthy controls who were matched in IQ and other neuropsychological functions. Overall, our results provide substantial evidence to support that time-based PM deficits in first-episode schizophrenia are apparent and not entirely attributable to other neuropsychological deficits. PM may constitute a neuropsychological marker for schizophrenia., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Objective: Prospective memory (PM) refers to the ability to remember to perform actions in the future. Schizophrenia spectrum disorders show impairments in PM but neural correlates of these impairments remain unclear. The present study aimed to examine brain activation during PM to identify impairments in individuals with schizotypal personality features., Method: Nineteen participants with schizotypal features and 22 healthy controls participated in a functional MRI experiment while performing a PM task., Results: Results showed that the prefrontal cortex (including Brodmann Area [BA] 10), middle temporal gyrus, and precuneus were activated when performing the PM task compared with baseline. The schizotypal and control groups did not differ in behavioral PM performance. However, participants with schizotypal features showed decreased activations in the inferior and medial frontal lobes (BA 45, and 8)., Conclusions: These results confirmed that the PM network involves prefrontal cortex, including BA 10. The lower activation in prefrontal cortex of individuals with schizotypal features when performing a PM task indicates brain activation abnormality. Notably, this abnormality may occur in the absence of any behavioral manifestation. Our findings support the hypothesis of frontal lobe involvement in PM deficits observed in individuals with schizotypal features.