Lost in distractors: Reduced Autobiographical Memory Specificity and dispersed activation spreading over distractors in working memory

Improving usual care outcomes in major depression in youth by targeting memory specificity: A randomized controlled trial of adjunct computerized memory specificity training (c-MeST)

OBJECTIVE

Extending on previous findings that computerized Memory Specificity Training (c-MeST) improves memory specificity and depressive symptoms in Major Depressive Disorder (MDD) in adults, this study aimed to assess the effects of c-MeST in youth with MDD on memory specificity and depression in addition to other treatment.

METHODS

Participants aged 15-25 (N = 359, 76 % female; M age = 19.2, SD = 3.1), receiving predominantly psychological therapy or counseling (85 %) and/or antidepressants (52 %) were randomized to usual care and c-MeST or usual care. Cognitive and clinical outcomes were assessed at baseline and at one, three, and six-month follow-ups.

RESULTS

The usual care and c-MeST group reported higher memory specificity at one-month (d = 0.42, p = .022), but not at three or six months (d's < 0.15, p's > 0.05). The rate of MDE was numerically lower in the c-MeST group at each follow-up time-point, but group was not a statistically significant predictor at one month (64 % usual care and c-MeST vs. 68 % usual care, OR = 0.81, p = .606), three months (67 % usual care and c-MeST vs. 72 % usual care, OR = 0.64, p = .327) or six months (55 % usual care and c-MeST vs. 68 % usual care, OR = 0.56, p = .266). The usual care and c-MeST group did report lower depressive symptoms at one month (d = 0.42, p = .023) and six-months (d = 0.84, p = .001), but not three-months (d = 0.13, p > .05).

CONCLUSIONS

c-MeST may reduce symptoms in youth with MDD when provided alongside other treatments. However, there are significant limitations to this inference, including high attrition in the study and a need for more data on the acceptability of the intervention.

Transdiagnostic and transtherapeutic strategies for optimising autobiographical memory

Our memories for past personally experienced autobiographical events play an important role in therapy, irrespective of presenting issue, diagnoses or therapeutic modality. Here, we summarise evidence for how autobiographical memory abilities can influence our mental health and the relevance of this for the treatment of mental health problems. We then guide the reader through principles and strategies for optimising autobiographical memory within treatment. We ground these recommendations within research for stand-alone interventions for improving autobiographical memory and from studies of how to support the formation and retrieval of therapeutic memories. Options are given for clinicians to guide clients in improving retrieval of autobiographical memories within treatment, for improving autobiographical memory for the therapeutic experience itself, and for creating improvements in autobiographical memory that endure post-treatment. We also provide worksheets for clinicians to use within treatment.

Reducing the stickiness of negative memory retrieval through positive memory training in adolescents

BACKGROUND AND OBJECTIVES

Individuals at risk for depression exhibit a decreased ability to disengage from negative memory retrieval during times of mental distress, partly because they have difficulty retrieving positive memories to repair sad mood. In this study, we tested whether this persistent tendency for negative memory retrieval could be reduced in adolescents through repeated practice to retrieve positive autobiographical memories, namely Positive Memory Specificity Training (PMST). Further, we examined the impact of this intervention on secondary outcomes, including depressive symptoms, emotion regulation strategies, and fear of positive emotions.

METHODS

Adolescents (n = 68) between 16 and 18 years old were randomly allocated to either PMST or bogus control training. Persistent negative memory retrieval was assessed following the training using a behavioral decision-making task (Emotional Reversal Learning Task). Additionally, participants completed self-report measurements (e.g., depressive symptoms) before and two weeks after the training.

RESULTS

We found preliminary supportive evidence for a significant training effect such that adolescents following PMST showed less persistence in negative memory retrieval compared to those in the control group. Only for anhedonia a significant training effect was found, indicating a possible adverse effect of the intervention.

LIMITATIONS

The primary outcome was assessed only at post-intervention to prevent a potential learning effect due to repeated measurements. We cannot exclude the possibility that baseline individual differences contaminated our results. To examine possible adverse effects of PMST, larger sample are needed.

CONCLUSIONS

PMST may help to reduce persistent negative memory retrieval in adolescents. Recommendations for future studies are addressed.

Reducing Anhedonia in Major Depressive Disorder with Future Event Specificity Training (FEST): A Randomized Controlled Trial

Background

Improving future thinking, such as characteristics of specificity, detail, and use of mental imagery, may be one means to reduce anhedonia, particularly in a Major Depressive Episode (MDE) in which future thinking is impaired. The current study aimed to test this using a validated program, Future Event Specificity Training (FEST).

Methods

Participants (N = 177; 80.8% women; M age = 43.7, SD = 11.8) with a current depressive episode with anhedonia and high symptom severity were randomized to FEST or no FEST. Future thinking, anhedonia-related variables, and other clinical outcomes were assessed at baseline, one- and three-month follow-up.

Results

Relative to the control group, FEST was associated with significantly improved future thinking characteristics, a reduced likelihood of anhedonia (35.1% vs. 61.1%, p = .015), improvements on other anhedonia-related variables such as anticipatory (d = 0.63, p = .004) and anticipated pleasure for future events (d = 0.77, p < .001), and desirable clinical outcomes such as less people meeting criteria for an MDE (37.8% vs. 64.8%, p = .011), higher behavioural activation (d = 0.71, p = .001) and improved global functioning (d = 0.52, p = .017). Changes in future thinking were found to mediate the effect of FEST on anhedonia.

Conclusion

The quality of future thinking can be enhanced in Major Depression, and this leads to a substantially reduced likelihood of anhedonia, other significant clinical effects, and functional gains.

Brief inductions in episodic past or future thinking: effects on episodic detail and problem-solving

Episodic specificity inductions, involving brief training in recollecting episodic details, have been shown to improve subsequent performance on tasks involving remembering the past, imagining the future and problem solving. The current study examined if specificity inductions targeting self-referential past or future episodic thinking would have dissociable effects on generating past and future episodic detail and problem solving. Sixty-three participants were randomised to either a past self-referential or future self-referential episodic induction. All participants also completed a control task. Participants randomised to the self-referential future thinking induction generated more episodic details on past and future narrative tasks compared to a control task, whereas participants randomised to a self-referential past thinking induction showed similar performance to the control task. When examining within-group performance of participants randomised to the past or future induction, we found some evidence of dissociable effects of inductions on narrative generation tasks, but not on problem solving outcomes. Our findings suggest that self-referential inductions may be useful for increasing episodic specificity, but that the temporal distance and direction of the induction matters. We discuss our results in the context of the potential clinical utility of this approach for populations vulnerable to autobiographical memory disruption.

The current state of memory Specificity Training (MeST) for emotional disorders

Memory Specificity Training (MeST) is an intervention developed from basic science that has found clinical utility. MeST uses cued recall exercises to target the difficulty that some people with emotional disorders have in recalling personally experienced events. MeST is simple enough to be delivered alongside traditional interventions or online by artificial intelligence. Currently, research indicates MeST's effects are immediate but short-lived, and there is limited research indicating its superiority over established interventions. Future investigations must establish the dosage and specific components of MeST that are necessary for clinically significant effects. Further, it must establish the secondary processes (e.g., problem-solving) that mediate between MeST-driven improvements in memory and symptoms. Similar interventions that build upon the idea of training autobiographical memory specificity are also emerging and warrant further investigation.

A study protocol for a randomised trial of adjunct computerised memory specificity training (c-MeST) for major depression in youth: targeting cognitive mechanisms to enhance usual care outcomes in mental health settings

Background

Youth depression is highly prevalent and is related to impairments in academic, social and behavioural functioning. Evidence-based treatments are available, but many young people do not respond or sufficiently recover with first-line options, and a significant proportion experience relapse. Consequently, there is clear scope to enhance intervention in this critical period of early-onset depression. Memory specificity training (MeST) is a low-intensity intervention for depression that targets reduced specificity when recalling memories of the past, a common cognitive vulnerability in depression. This randomised controlled trial will assess the efficacy of adding a computerised version of MeST (c-MeST) to usual care for youth depression.

Methods/design

Young people aged 15–25 years with a major depressive episode (MDE) will be recruited and randomised to have immediate access to the seven session online c-MeST program in addition to usual care, or to usual care and wait-list for c-MeST. The primary outcomes will be diagnostic status of an MDE and self-reported depressive symptoms assessed at baseline, 1-, 3- and 6-month intervals. Autobiographical memory specificity and other variables thought to contribute to the maintenance of reduced memory specificity and depression will be assessed as mediators of change.

Discussion

Online provision of c-MeST provides a simple, low-intensity option for targeting a cognitive vulnerability that predicts the persistence of depressive symptoms. If found to be efficacious as an adjunct to usual care for depressed youth, it could be suitable for broader roll-out, as c-MeST is highly accessible and implementation requires only minimal resources due to the online and automated nature of intervention.

Trial registration

Australian New Zealand Clinical Trials Registry, ACTRN12619000234112p. Registered on the 18 February 2019. All items from the WHO Trial Registration Data Set can be found within the protocol.

Protocol version

1.0

Remediating reduced memory specificity in bipolar disorder: A case study using a Computerized Memory Specificity Training

OBJECTIVES

Reduced autobiographical memory specificity (rAMS) is a vulnerability factor found across unipolar depression (UD), posttraumatic stress disorder (PTSD), eating disorder, schizophrenia, and bipolar disorder (BD). A group delivered psychological therapy training called Memory Specificity Training (MeST) remediates rAMS in UD and PTSD, with additional downstream effects on related psychological processes and symptoms. Its impact in BD is unknown. In this case study, we examined the impact of a computerized version of MeST (c-MeST) on improving AMS and related symptoms and processes in participant with rapid cycling type I BD.

METHOD

An experimental case study with an ABA design was used. During baseline (14 days, Phase A), the training phase (nine sessions across 17 days, Phase B), and a 1-month follow-up (Phase A), memory specificity, depressive symptoms, and related processes and symptoms were repeatedly measured.

RESULTS

Memory specificity increased significantly after the participant completed c-MeST. Session-to-session scores indicated that AMS improved most from the in-person baseline assessment to the first online session. All other measures of processes and symptoms deteriorated during the training phase but regressed to baseline during follow-up.

CONCLUSION

Memory specificity was improved as indicated by increased AMS from pre-intervention measurement to 1-month follow-up. Other improvements in symptoms were not observed. Rather, some related maladaptive psychological processes and symptoms worsened during the training phase and regressed to baseline during follow-up.

Efficacy of online Memory Specificity Training in adults with a history of depression, using a multiple baseline across participants design

BACKGROUND AND OBJECTIVES

Memory Specificity Training (MeST), a group training protocol, is effective in improving autobiographical memory specificity (AMS), and in so doing, reducing emotional disorder symptoms amongst clinical groups. We examined MeST's effectiveness when the core component (memory specificity trials) is offered online and individually (c-MeST).

METHODS

A multiple-baseline across-participants design with a randomization-to-baseline length (14 to 33 days) was used. Participants were twenty adults (16 female; M age  = 50, SD = 12) experiencing reduced AMS, at least one lifetime depressive episode and who currently reported at least minimal depressive symptoms. During baseline, the training phase (nine sessions across 17 days) and a three-month follow-up assessment, AMS, depressive symptoms and related processes were measured.

RESULTS

AMS improved significantly by three months follow-up. Session-to-session scores indicated that AMS improved most from baseline to the first online session, with no further improvement thereafter. In contrast to studies with clinical participants, no significant change in symptoms or secondary processes such as rumination was found.

CONCLUSIONS

Translating MeST into an online, individual version is a feasible, low-cost intervention for reduced AMS. Future research should examine c-MeST's potential for preventing increases in symptoms in at-risk samples with longer follow-ups as well as its potential for reducing symptoms in clinical groups.

Remediating Reduced Autobiographical Memory in Healthy Older Adults With Computerized Memory Specificity Training (c-MeST): An Observational Before-After Study

Background

The ability to retrieve specific autobiographical memories decreases with cognitive aging. This decline is clinically relevant due to its association with impairments in problem solving, daily functioning, and depression. A therapist-delivered group training protocol, Memory Specificity Training (MeST), has been shown to enhance the retrieval of specific memories while ameliorating the impairments and negative outcomes associated with reduced specificity. The therapist-delivered nature of this intervention means it is relatively expensive to deliver and difficult for people with mobility impairments, such as older people, to receive.

Objective

The objective of this study was to test if a novel, Web-based computerized version of a group training protocol called Memory Specificity Training, has the potential to increase autobiographical memory specificity and impact associated secondary psychological processes.

Methods

A total of 21 participants (13 female; mean age 67.05, SD 6.55) who experienced a deficit in retrieving specific autobiographical memory were trained with c-MeST. We assessed memory specificity at preintervention and postintervention, as well as secondary processes such as depressive symptoms, rumination, and problem-solving skills.

Results

Memory specificity increased significantly after participants completed c-MeST (r=.57). Session-to-session scores indicated that autobiographical memory specificity improved most from the online baseline assessment to the first Web-based session. Symptoms or secondary processes such as problem-solving skills did not change significantly.

Conclusions

A Web-based automated individual version of MeST is a feasible, low-cost intervention for reduced memory specificity in healthy older adults. Future studies should clarify the preventive impact of c-MeST in other at-risk sample populations with longer follow-up times.

Computerised memory specificity training (c-MeST) for the treatment of major depression: a study protocol for a randomised controlled trial

INTRODUCTION

Major depression is a prevalent and debilitating disorder, but many sufferers do not receive support or respond to current treatments. The development of easily accessible and low-intensity treatments that have clear cognitive mechanisms of change is indicated. Memory specificity training (MeST) is an intervention for depression that targets deficits in recalling detailed memories of past experiences through repeated practice of autobiographical memory retrieval. This randomised controlled trial will assess the efficacy of an online, computerised version of MeST (c-MeST).

METHODS AND ANALYSIS

Adults aged 18 and over with a current major depressive episode (MDE) will be recruited and randomised to have access to the seven session, online c-MeST programme for 2 weeks, or to a wait-list control group. The primary outcomes will be diagnostic status of MDE and self-reported depressive symptoms at postintervention. One-month and three-month follow-ups will be collected. Increases in autobiographical memory specificity will be assessed as a mediator of change, as well as other variables thought to contribute to reduced memory specificity, such as rumination and cognitive avoidance.

ETHICS AND DISSEMINATION

Ethics approval has been granted by the Deakin University Human Research Ethics Committee to conduct the study (ID: 2017_168). The findings will be disseminated through scholarly publications and workshops and will inform future trials, such as with an active comparator or as an adjunct treatment.

TRIAL REGISTRATION NUMBER

ACTRN12618000257268; Pre-results.

The computerized scoring algorithm for the autobiographical memory test: updates and extensions for analyzing memories of English-speaking adults

The Autobiographical Memory Test (AMT) has been central in psychopathological studies of memory dysfunctions, as reduced memory specificity or overgeneralised autobiographical memory has been recognised as a hallmark vulnerability for depression. In the AMT, participants are asked to generate specific memories in response to emotional cue words, and their responses are scored by human experts. Because the manual coding takes some time, particularly when analysing a large dataset, recent studies have proposed computerised scoring algorithms. These algorithms have been shown to reliably discriminate between specific and non-specific memories of English-speaking children and Dutch- and Japanese-speaking adults. The key limitation is that the algorithm is not developed for English-speaking adult memories, which may cover a wider range of vocabulary that the existing algorithm for English-speaking child memories cannot process correctly. In the present study, we trained a new support vector machine to score memories of English-speaking adults. In a performance test (predicting memory specificity against human expert coding), the adult-memory algorithm outperformed the child-memory variant. In another independent performance test, the adult-memory algorithm showed robust performances to score memories that were generated in response to a different set of cues. These results suggest that the adult-memory algorithm reliably scores memory specificity.