Do memory complaints represent impaired memory performance in patients with major depressive disorder?

Cognitive Safety Data from a Randomized, Double-Blind, Parallel-Group, Placebo-Controlled Phase IIb Study of the Effects of a Cannabidiol and Δ9-Tetrahydrocannabinol Drug on Parkinson's Disease-Related Motor Symptoms

BACKGROUND

Cannabis is increasingly available worldwide but its impact on cognition in Parkinson's disease (PD) is unknown.

OBJECTIVE

Present cognitive safety data from study of an oral high-dose cannabidiol (CBD; 100 mg) and low-dose Δ9-tetrahydocannabinol (THC; 3.3 mg) drug in PD.

METHODS

Randomized, double-blind, parallel-group, placebo-controlled study of a CBD/THC drug administered for 16.3 (SD: 4.2) days, with dosage escalating to twice per day. Neuropsychological tests were administered at baseline and 1-1½ hours after final dose; scores were analyzed with longitudinal regression models (alpha = 0.05). Cognitive adverse events were collected.

RESULTS

When adjusted for age and education, the CBD/THC group (n = 29) performed worse than the placebo group (n = 29) on Animal Verbal Fluency. Adverse cognitive events were reported at least twice as often by the CBD/THC than the placebo group.

CONCLUSION

Data suggest this CBD/THC drug has a small detrimental effect on cognition following acute/short-term use in PD. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Objective Cognitive Outcomes and Subjective Emotional Sequelae in Litigating Adults with a Traumatic Brain Injury: The Impact of Performance and Symptom Validity Measures

OBJECTIVE

This study examined the relative contribution of performance and symptom validity in litigating adults with traumatic brain injury (TBI), as a function of TBI severity, and examined the relationship between self-reported emotional symptoms and cognitive tests scores while controlling for validity test performance.

METHOD

Participants underwent neuropsychological assessment between January 2012 and June 2021 in the context of compensation-seeking claims related to a TBI. All participants completed a cognitive test battery, the Personality Assessment Inventory (including symptom validity tests; SVTs), and multiple performance validity tests (PVTs). Data analyses included independent t-tests, one-way ANOVAs, correlation analyses, and hierarchical multiple regression.

RESULTS

A total of 370 participants were included. Atypical PVT and SVT performance were associated with poorer cognitive test performance and higher emotional symptom report, irrespective of TBI severity. PVTs and SVTs had an additive effect on cognitive test performance for uncomplicated mTBI, but less so for more severe TBI. The relationship between emotional symptoms and cognitive test performance diminished substantially when validity test performance was controlled, and validity test performance had a substantially larger impact than emotional symptoms on cognitive test performance.

CONCLUSION

Validity test performance has a significant impact on the neuropsychological profiles of people with TBI, irrespective of TBI severity, and plays a significant role in the relationship between emotional symptoms and cognitive test performance. Adequate validity testing should be incorporated into every neuropsychological assessment, and associations between emotional symptoms and cognitive outcomes that do not consider validity testing should be interpreted with extreme caution.

The Relationship Between Cognitive Functioning and Symptoms of Depression, Anxiety, and Post-Traumatic Stress Disorder in Adults with a Traumatic Brain Injury: a Meta-Analysis

A thorough understanding of the relationship between cognitive test performance and symptoms of depression, anxiety, or post-traumatic stress disorder (PTSD) in people with traumatic brain injury (TBI) is important given the high prevalence of these emotional symptoms following injury. It is also important to understand whether these relationships are affected by TBI severity, and the validity of test performance and symptom report. This meta-analysis was conducted to investigate whether these symptoms are associated with cognitive test performance alterations in adults with a TBI. This meta-analysis was prospectively registered on the PROSPERO International Prospective Register of Systematic Reviews website (registration number: CRD42018089194). The electronic databases Medline, PsycINFO, and CINAHL were searched for journal articles published up until May 2020. In total, 61 studies were included, which enabled calculation of pooled effect sizes for the cognitive domains of immediate memory (verbal and visual), recent memory (verbal and visual), attention, executive function, processing speed, and language. Depression had a small, negative relationship with most cognitive domains. These relationships remained, for the most part, when samples with mild TBI (mTBI)-only were analysed separately, but not for samples with more severe TBI (sTBI)-only. A similar pattern of results was found in the anxiety analysis. PTSD had a small, negative relationship with verbal memory, in samples with mTBI-only. No data were available for the PTSD analysis with sTBI samples. Moderator analyses indicated that the relationships between emotional symptoms and cognitive test performance may be impacted to some degree by exclusion of participants with atypical performance on performance validity tests (PVTs) or symptom validity tests (SVTs), however there were small study numbers and changes in effect size were not statistically significant. These findings are useful in synthesising what is currently known about the relationship between cognitive test performance and emotional symptoms in adults with TBI, demonstrating significant, albeit small, relationships between emotional symptoms and cognitive test performance in multiple domains, in non-military samples. Some of these relationships appeared to be mildly impacted by controlling for performance validity or symptom validity, however this was based on the relatively few studies using validity tests. More research including PVTs and SVTs whilst examining the relationship between emotional symptoms and cognitive outcomes is needed.

Memory awareness in patients with Major Depressive Disorder

BACKGROUND

Subjective Memory Complaints (SMC) along with cognitive deficits are frequently observed in patients with Major Depressive Disorder (MDD). The relationship between SMC and objective memory performance in patients with MDD was evaluated, in comparison with patients with Mild Cognitive Impairment due to Alzheimer's Disease (MCI-AD) and healthy controls (HC).

METHODS

Patients with MDD (n = 47), MCI-AD (n = 43) and HC (n = 45) were assessed with a self-report memory complaints scale (SMCS) and underwent a comprehensive clinical and neuropsychological assessment. A discrepancy score between the Logical Memory delayed recall and the SMCS total score was calculated as a measure of memory awareness.

RESULTS

Patients with MDD (12.5 ± 4.4) and patients with MCI-AD (10.9 ± 4.1) had not significantly different SMCS total scores, whereas HC showed significantly lower scores (4.0 ± 3.0). As much as 74.5% of patients with MDD patients and 65.1% of patients with MCI-AD reported prominent memory complaints, whereas only 4.4% of HC did. Patients with MDD had relatively preserved memory tests, resulting in a higher discrepancy score than both patients with MCI-AD and HC. The SMCS total score correlated positively with depressive symptoms in the 3 groups of participants.

CONCLUSIONS

Patients with MDD showed inaccurate memory self-awareness as they under-estimated their memory functioning, a pattern distinct from both patients with MCI-AD and HC.

Cognitive remediation therapy for partially remitted unipolar depression: A single-blind randomized controlled trial

BACKGROUND

There is an urgent need for the development and evaluation of targeted interventions for cognitive impairment (CI) in patients with (partially) remitted major depressive disorder (MDD). The aim of our study was therefore to evaluate the effect of cognitive remediation therapy (CRT) on cognitive and psychosocial functioning in a sample of patients with MDD, taking into account comorbidity, psychopathology, remission status and CI profile. Furthermore, we compared a generalized training (GT) with an individualized training (IT) approach regarding their effects on cognition.

METHODS

Sixty-two MDD patients in partial remission with CI were randomly assigned to a control group (CG), IT or GT. Participants of GT trained six cognitive subdomains (divided attention, selective attention, alertness, working memory, planning and response inhibition), whereas participants of IT trained their three most deficient cognitive subdomains as identified at baseline. Participants of both intervention groups trained three times per week over a five-week period. Both training groups received additional 30-minute compensatory-transfer sessions once per week.

RESULTS

Attention appeared to be the most frequently impaired cognitive domain as well as the domain which was significantly improved by CRT, with medium to large effect sizes. No difference in improvement was found between IT and GT. The analyses also revealed greater improvement in self-assessed psychosocial functioning in training participants (GT and IT combined) compared to the CG.

LIMITATIONS

Due to the small sample size, the present results are preliminary in nature.

CONCLUSION

CRT was well accepted, and patients transferred the attentional improvement to real life, as measured by self-assessed psychosocial functioning. IT yielded no additional advantages over GT. We propose CRT as an integral part of the treatment plan for patients with depression suffering from CI.

Decision-making in major depressive disorder: Subjective complaint, objective performance, and discrepancy between both

BACKGROUND

Studies comparing objective and subjective cognition in major depressive disorder (MDD) are scarce, and available data concern different cognitive functions but not decision-making specifically. This cross-sectional study aimed to explore objective (O-DMI) and subjective decision-making impairment (S-DMI) as well as the discrepancy between both in people with MDD. Secondly, we assessed the association between S-DMI and O-DMI. Finally, we explored sociodemographic, clinical, and psychosocial factors related to decision-making impairment status.

METHOD

One hundred and nine people with MDD were assessed with the Iowa Gambling Task to identify "O-DMI". The item 9 of the Beck Depression Inventory was used to compose the variable "S-DMI". Psychiatric history, medication adherence, childhood trauma, physical and psychological pain, and negative life experiences were also collected.

RESULTS

Forty-six percent of participants have O-DMI and 65.1% S-DMI. From 49.5% showing a discrepancy between both, 68,6% have positive discrepancy and 31,4% negative (i.e. under and overestimation respectively). O-DMI and S-DMI were not associated. Binary logistic regressions showed that the number of negative life events in the past 6 months was predictor of O-DMI, while depression severity and medication adherence predicted S-DMI. Finally, medication adherence and depression severity predicted the type of discrepancy.

LIMITATIONS

The variable S-DMI was obtained through a single item.

CONCLUSION

These results confirm the lack of association between objective and subjective measures of cognition in MDD, and for the first-time concerning decision-making. This suggest that both assessments should be done in order to have a deeper knowledge of the cognitive functioning of each patient.

"Cold" Cognitive Control and Attentional Symptoms in Anxiety: Perceptions Versus Performance

Clinically significant anxiety is associated with an array of attentional symptoms (e.g., difficulty concentrating; unwanted thought) that are subjectively experienced as severe. However, neuropsychological findings are mixed with respect to the presence of cognitive deficits that can account for these symptoms. Contextualizing predictions from established clinical theories (e.g., Attentional Control Theory) within contemporary, neurobiologically derived models of cognitive control (Dual Mechanisms of Control Theory), the present study investigated the relationship between "cold" proactive and reactive cognitive control, task effort, and subjective attentional symptoms (difficulty concentrating; unwanted thought) in a mixed clinical sample of individuals with generalized anxiety disorder (GAD) and/or obsessive-compulsive disorder (OCD) and a comparison sample of healthy controls. Clinical status moderated the relationship between attentional symptoms (attentional focusing and trait worry) and proactive cognitive control response time. Clinical status also moderated the relationship between trait worry and task effort. Higher trait worry was associated with slower proactive control and lower effort in healthy participants, but faster proactive control in clinical participants. Self-reported attentional focusing showed differential validity vis-à-vis proactive control response time in clinical versus healthy participants. Post-hoc conditional effects analysis suggested more accurate self-appraisals in healthy controls, but was not significant after correction for multiple comparisons. Preliminary evidence suggested that differences in task effort in anxious versus healthy adults may relate to subjective attentional symptoms in GAD and OCD.

Eveningness is associated with greater subjective cognitive impairment in individuals with self-reported symptoms of unipolar depression

BACKGROUND

Eveningness is associated with depression diagnosis and increased depressive symptom severity. Time-of-day preference has been linked with differences in cognitive function in the general population, with cognitive difficulties being a major factor in psychosocial impairment in depression. We therefore investigated the impact of time-of-day preference and self-reported depressed state on subjective cognitive function.

METHODS

Participants over the age of 18 with a self-reported history of depression completed an online questionnaire. They provided demographic and mental health information, and completed self-report scales assessing depression symptoms, time-of-day preference, and cognition. Participants were classified as "currently" or "previously depressed" based on self-reported symptoms, and as having a morning, neither, or evening time-of-day preference.

RESULTS

A total of 804 participants reporting a history of unipolar depression were included. Currently-depressed participants reported more cognitive difficulties in all areas measured. Evening types reported more complex attentional and retrospective memory difficulties than neither types, and reported more executive and prospective memory difficulties than both neither and morning types. There was an additive effect of mood state and time-of-day preference, with self-reported depressed evening types reporting the most cognitive problems.

LIMITATIONS

Depression history, time-of-day preference, and cognitive function were assessed using unsupervised self-report measures. Time-of-day preference does not necessarily reflect the physiological circadian system.

CONCLUSIONS

Both depressed state and evening preference were individually associated with subjective cognitive complaints in people with a self-reported history of unipolar depression. The additive effect of poor mood and eveningness is important given the high prevalence of eveningness in depression. Assessment of time-of-day preference could help to identify those susceptible to cognitive symptoms, and inform treatment.

Treatment effects on residual cognitive symptoms among partially or fully remitted patients with major depressive disorder: A randomized, double-blinded, exploratory study with vortioxetine

BACKGROUND

Residual cognitive symptoms in major depressive disorder (MDD) are common, yet poorly investigated. We explored the effectiveness of vortioxetine as adjunctive treatment to selective serotonin reuptake inhibitors (SSRI) and as monotherapy versus continued SSRI, in patients with MDD who achieved full or partial remission with SSRI, but report residual cognitive symptoms.

METHODS

Patients (18-65 years old, N =151) diagnosed with MDD, with a Hamilton Depression Rating Scale 17-items total score ≤10 and a Perceived Deficits Questionnaire-Depression total score >25, were randomized 1:1:1 to 8 weeks of double-blind treatment with current SSRI + placebo, SSRI + vortioxetine (10-20 mg/day), or vortioxetine (10-20 mg/day) + placebo. The primary efficacy measure was the Digit Symbol Substitution Test (DSST), analyzed using a mixed model for repeated measurements. Secondary outcomes comprised cognitive functioning, subjectively-rated cognitive symptoms, patient functioning, and mood symptoms.

RESULTS

From baseline to week 8, all treatment groups improved DSST performance, with statistically nonsignificant treatment differences. Similar results were seen for secondary endpoints. Improvement in cognitive performance tended to be numerically larger with vortioxetine monotherapy than with SSRI monotherapy, while vortioxetine as adjunctive treatment tended to perform numerically better in further improving depressive symptoms. Most adverse events were mild or moderate. Nausea was the most common adverse event for vortioxetine.

LIMITATIONS

Small sample sizes limited statistical power.

CONCLUSION

In this explorative study, remitted patients with MDD improved their cognitive performance with no treatment differences. Secondary results indicate numerical benefits for cognitive performance with vortioxetine monotherapy, and for depressive symptoms with vortioxetine augmentation.

Cognitive complaints and predictors of perceived cognitive dysfunction in adults with major depressive disorder: Findings from the Cognitive Dysfunction in Asians with Depression (CogDAD) study

BACKGROUND

Several studies have described the presence of perceived cognitive dysfunction amongst Asian patients with major depressive disorder (MDD). To date, no study has been conducted investigating the predictors of perceived cognitive dysfunction amongst Asian MDD patients.

METHODS

This was a post-hoc analysis of the Cognitive Dysfunction in Asian patients with Depression (CogDAD) study. Descriptive statistics were used to describe the most common cognitive complaints by patients. Univariate and multivariate analyses were performed to determine variables associated with perceived cognitive dysfunction (Perceived Deficit Questionnaire-Depression, PDQ-D).

RESULTS

The CogDAD study population is comprised of MDD patients with mild-to-moderate depression (Patient Health Questionnaire 9-item [PHQ-9]: 11.3 ± 6.9) who reported perceived cognitive dysfunction (PDQ-D = 22.6 ± 16.2). The most common cognitive complaints were: mind drifting (42.3%), trouble making decision (39.6%) and trouble concentrating (38.0%). Predictors of perceived cognitive dysfunction were: being Southeast Asians (vs. Taiwanese) (p < 0.001), current episode longer than 8 weeks (vs. 1-8 weeks) (p < 0.05), the presence of disability (vs. no disability) (p < 0.05), younger age (p < 0.01), and higher PHQ-9 total scores (p < 0.001).

LIMITATIONS

The causal relationship between predictive variables and PDQ-D could not be tested due to the cross-sectional nature of the study. Furthermore, a neuropsychological test was not included in the CogDAD study and use of concomitant medications, including anti-depressants, could have impacted patient's perceived cognitive ability.

CONCLUSIONS

The present study results suggest a potential role for subjective cognitive assessment in patients with MDD who are young, with long durations of depression or severe depression.

Difficulty concentrating in generalized anxiety disorder: An evaluation of incremental utility and relationship to worry

Difficulty concentrating is one of the most common diagnostic criteria across DSM-5 categories, especially within the emotional (mood- and anxiety-related) disorders. A substantial literature has characterized cognitive functioning in emotional disorders using objective (behavioral) computerized cognitive tasks. However, diagnoses are typically formed on the basis of subjective (self-reported; clinician-rated) assessments of symptoms, and little is known about difficulty concentrating as a symptom. These questions are particularly important for generalized anxiety disorder (GAD), which has long been the subject of nosological debates, and for which several theoretical models that suggest a central role for cognitive impairments (including difficulty concentrating) in the maintenance of psychopathology have been proposed. The present study evaluated the incremental utility of difficulty concentrating and its relationship to worry and other symptoms in 175 GAD-diagnosed adults. Clinician-assessed difficulty concentrating incrementally predicted clinician-rated GAD, anxiety, and depression severity even after other GAD symptoms were controlled. Consistent with theoretical models of GAD that propose a direct relationship between worry and cognitive impairment, difficulty concentrating mediated the relationship between trait worry and clinical severity. These findings suggest that difficulty concentrating has value as a diagnostic criterion and is a potential mechanism by which worry increases distress and impairment.

Discrepancy between objective and subjective cognition in adults with major depressive disorder

This study aimed to determine: i) the correlation between objective and subjective cognition, ii) the correlates of objective and subjective cognition and iii) the predictors of discrepancy between objective and subjective cognition. Participants were non-elderly patients with major depressive disorder (MDD). We assessed subjective cognition using the Perceived Deficit Questionnaire for Depression (PDQ-D) and objective cognition using Face I and Face II tests of the Wechsler Memory Scale, 3rd edition and Digit Span and Matrix Reasoning tests of the Wechsler Intelligence Scale for Adults, 3rd edition. The discrepancy between objective and subjective cognition was estimated. Participants were 57 outpatients with MDD. PDQ-D scores were not correlated with composite neurocognitive test (NCT) z scores. Years of education significantly predicted composite NCT z scores, as did age. The 9-item Patient Health Questionnaire (PHQ-9) scores significantly predicted PDQ-D scores, as did antidepressant treatment. Age significantly predicted discrepancy scores, as did PHQ-9 scores. In conclusion, objective and subjective cognition in patients with MDD are not correlated. Age and education predict objective cognition. Depression. severity and antidepressant treatment predict subjective cognition. Age and depression severity may predict the discrepancy between objective and subjective cognition.

Effectiveness of Working Memory Training among Subjects Currently on Sick Leave Due to Complex Symptoms

Introduction: The current study examined if adaptive working memory training (Cogmed QM) has the potential to improve inhibitory control, working memory capacity, and perceptions of memory functioning in a group of patients currently on sick leave due to symptoms of pain, insomnia, fatigue, depression and anxiety. Participants who were referred to a vocational rehabilitation center volunteered to take part in the study. Methods: Participants were randomly assigned to either a training condition (N = 25) or a control condition (N = 29). Participants in the training condition received working memory training in addition to the clinical intervention offered as part of the rehabilitation program, while participants in the control condition received treatment as usual i.e., the rehabilitation program only. Inhibitory control was measured by The Stop Signal Task, working memory was assessed by the Spatial Working Memory Test, while perceptions of memory functioning were assessed by The Everyday Memory Questionnaire-Revised. Results: Participants in the training group showed a significant improvement on the post-tests of inhibitory control when compared with the comparison group (p = 0.025). The groups did not differ on the post-tests of working memory. Both groups reported less memory problems at post-testing, but there was no sizeable difference between the two groups. Conclusions: Results indicate that working memory training does not improve general working memory capacity per se. Nor does it seem to give any added effects in terms of targeting and improving self-perceived memory functioning. Results do, however, provide evidence to suggest that inhibitory control is accessible and susceptible to modification by adaptive working memory training.

Subjektive Einschätzung und objektive kognitive Leistung bei psychisch Gesunden

Zusammenfassung. Neuropsychologische Untersuchungen verweisen auf uneinheitliche Zusammenhänge zwischen der subjektiven und objektiven kognitiven Leistungsbeurteilung. Bei 286 psychisch Gesunden wurden objektive kognitive Leistungswerte in der deutschen Adaptation der Neuropsychological Assessment Battery (NAB) sowie der Fragebogen zur subjektiven Einschätzung der geistigen Leistungsfähigkeit (FLei) erhoben. Trotz sehr guter Reliabilitäten des FLei limitierten Bodeneffekte die Aufdeckung richtungskonformer Zusammenhänge mit objektiven Leistungswerten in den Bereichen Aufmerksamkeit, Gedächtnis und exekutiven Funktionen. Dennoch erwies sich die Gedächtnisleistung als sensitivste Einzeldomäne für einen positiven Zusammenhang zwischen subjektiver und objektiver Leistungseinschätzung. Dabei moderierte das subjektive Wohlbefinden (WHO-5-Index) den Zusammenhang beider (subjektiver/objektiver) Ebenen im Gedächtnisbereich und in der kognitiven Gesamtleistung. Vor dem Hintergrund dieses Ergebnismusters sollten zukünftige Zusammenhangsanalysen insbesondere bei Personen mit psychischen Belastungen zu weiteren klinisch relevanten Befunden führen.

The interplay between cognitive risk and resilience factors in remitted depression: A network analysis

BACKGROUND

Individuals in remission from depression are at increased risk for developing future depressive episodes. Several cognitive risk- and resilience factors have been suggested to account for this vulnerability. In the current study we explored how risk- and protective factors such as cognitive control, adaptive and maladaptive emotion regulation, residual symptomatology, and resilience relate to one another in a remitted depressed (RMD) sample.

METHODS

We examined the relationships between these constructs in a cross-sectional dataset of 69 RMD patients using network analyses in order to obtain a comprehensive, data-driven view on the interplay between these constructs. We subsequently present an association network, a concentration network, and a relative importance network.

RESULTS

In all three networks resilience formed the central hub, connecting perceived cognitive control (i.e., working memory complaints), emotion regulation, and residual symptomatology. The contribution of the behavioral measure for cognitive control in the network was negligible. Moreover, the directed relative importance network indicates bidirectional influences between these constructs, with all indicators of centrality suggesting a key role of resilience in remission from depression.

LIMITATIONS

The presented findings are cross-sectional and networks are limited to a fixed set of key constructs in the literature pertaining cognitive vulnerability for depression.

CONCLUSIONS

These findings indicate the importance of resilience to successfully cope with stressors following remission from depression. Further in-depth studies will be essential to identify the specific underlying resilience mechanisms that may be key to successful remission from depression.

Subjective memory complaints among patients on sick leave are associated with symptoms of fatigue and anxiety

Objective: The aim of this study was to identify symptoms associated with subjective memory complaints (SMCs) among subjects who are currently on sick leave due to symptoms of chronic pain, fatigue, depression, anxiety, and insomnia.

Methods: This was a cross-sectional study, subjects (n = 167) who were currently on sick leave were asked to complete an extensive survey consisting of the following: items addressing their sociodemographics, one item from the SF-8 health survey measuring pain, Chalder Fatigue Questionnaire, Hospital Anxiety and Depression Scale, Insomnia Severity Index, and Everyday Memory Questionnaire – Revised. General linear modeling was used to analyze variables associated with SMCs.

Results: Symptoms of fatigue (p-value < 0.001) and anxiety (p-value = 0.001) were uniquely and significantly associated with perceived memory failures. The associations with symptoms of pain, depression, and insomnia were not statistically significant.

Conclusions: Subjective memory complaints should be recognized as part of the complex symptomatology among patients who report multiple symptoms, especially in cases of fatigue and anxiety. Self-report questionnaires measuring perceived memory failures may be a quick and easy way to incorporate and extend this knowledge into clinical practice.

The neuroscience of positive memory deficits in depression

Adults with unipolar depression typically show poor episodic memory for positive material, but the neuroscientific mechanisms responsible for this deficit have not been characterized. I suggest a simple hypothesis: weak memory for positive material in depression reflects disrupted communication between the mesolimbic dopamine pathway and medial temporal lobe (MTL) memory systems during encoding. This proposal draws on basic research showing that dopamine release in the hippocampus is critical for the transition from early- to late-phase long-term potentiation (LTP) that marks the conversion of labile, short-term memories into stable, long-term memories. Neuroimaging and pharmacological data from healthy humans paint a similar picture: activation of the mesolimbic reward circuit enhances encoding and boosts retention. Unipolar depression is characterized by anhedonia-loss of pleasure-and reward circuit dysfunction, which is believed to reflect negative effects of stress on the mesolimbic dopamine pathway. Thus, I propose that the MTL is deprived of strengthening reward signals in depressed adults and memory for positive events suffers accordingly. Although other mechanisms are important, this hypothesis holds promise as an explanation for positive memory deficits in depression.

Subjective memory and concentration deficits in medication-free, non-elderly Asians with major depressive disorder: prevalence and their correlates

BACKGROUND

Subjective cognitive impairment (SCI) in major depressive disorder (MDD) is prevalent and correlated with disability. This study aimed to examine the prevalence rates and correlates of subjective memory deficit (SMD) and subjective concentration deficit (SCD) in medication-free, non-elderly Asians with MDD.

METHODS

The SMD and SCD were assessed by using two items of the Symptom Checklist-90-Revised (SCL-90-R). Other measurements of interest included the Montgomery-Asberg Depression Rating Scale (MADRS), the Fatigue Severity Scale (FSS), the Sheehan Disability Scale (SDS), and the Short Form Health Survey (SF-36). Adjusted odds ratios with 95% confidence intervals were calculated.

RESULTS

Of 515 participants from China, Korea, Malaysia, Singapore, Taiwan, and Thailand, 347 (67.4%) and 377 (73.2%) had SMD and SCD, respectively. In total, 420 participants (81.6%) had SMD alone, SCD alone, and both deficits. Severe depression and poor mental health were significant correlates of SMD. Severe depression, clinically significant disability, poor physical health, and poor mental health were significantly independent correlates of SCD. Compared with young adults (18-34 years), older adults aged 50-65 years had a significantly lower risk of SCD (OR=.33, 95% CI: .19-.57).

LIMITATIONS

Only two SCL-90-R items were used to assess the SMD and SCD. The exclusion of MDD patients treated with psychotropic medications eliminated many patients commonly seen in typical clinic settings.

CONCLUSION

SMD and SCD are prevalent in medication-free, non-elderly Asians with MDD. Both deficits are correlated with depression and mental health status. The independent correlation between SCD and disability underscores the crucial role of SCI in MDD.

The association between the subjective memory complaints scale and depressive state and cognitive impairment: a factor analysis

BACKGROUND

We aimed to discriminate individuals with depressive state from individuals with cognitive impairment among community-dwelling people using the subjective memory complaints (SMC) scale.

METHODS

The study group consisted of 289 volunteers (over 60 years old; 104 males and 185 females). Participants' SMCs were assessed using the SMC scale. The Japanese version of the Center for Epidemiologic Studies for Depression scale and the Mini-Mental State Examination were administered. Participants whose Center for Epidemiologic Studies for Depression scores were 16 or higher were defined as the depressive group and participants whose Mini-Mental State Examination scores were less than 24 were defined as the cognitive impairment group. Exploratory factor analysis was performed to identify the factor structure of the items of the SMC scale. A multiple logistic regression analysis of the association between depressive state and cognitive impairment and the score of each factor was performed.

RESULTS

In the final factor analysis model, six items of the SMC scale remained, and a two-factor structure was adequate. Factor 1 included the items 8, 9, and 10 about thought or the ability to think; thus, Factor 1 was defined as "thought disturbance factor". Factor 2 included the items 1, 2, and 4 about memory or forgetfulness; thus, Factor 2 was defined as "memory disturbance factor". In the multiple logistic regression analysis, Factor 1 was significantly associated with depressive state and Factor 2 was significantly associated with cognitive impairment.

CONCLUSION

For individuals with SMCs, we might be able to discriminate depressive state or depression from cognitive impairment or dementia through a detailed investigation using the SMC scale.

Subjective memory complaints and memory performance in patients with borderline personality disorder

BACKGROUND

It is still a matter of debate as to whether patients with Borderline Personality Disorder (BPD) suffer from memory deficits. Existing studies indicate no or small impairments in memory test performance. However, it was shown in patients with related disorders, such as depression, that self-reported impairment exceeds test malfunction. In the present study we assessed memory performance of BPD patients through the use of memory tests and a questionnaire for subjective memory complaints (SMC) in everyday life.

METHODS

Thirty-two patients with BPD and 32 healthy control subjects were included in the study. The groups of subjects were comparable with respect to age, education, and gender. Subjects completed verbal and nonverbal memory tests, as well as the everyday memory questionnaire (EMQ).

RESULTS

BPD patients reported severe SMC but did not show memory test impairment. The results remained stable even when all BPD patients with acute or lifetime depression comorbidity were excluded from analyses. In both groups, SMC and test performances were not related but in BPD patients SMC were related to BPD symptoms.

CONCLUSIONS

Our data indicate memory impairment of BPD patients in everyday life. However, it cannot be ruled out that increased memory complaints result from patients' negative self-perception. Future research needs to clarify the reasons for memory complaints of BPD patients.

Sex-specific effects of subjective memory complaints with respect to cognitive impairment or depressive symptoms

AIM

The aim of this study was to investigate the association between subjective memory complaints (SMC) and sex.

METHODS

We researched the prevalence of SMC in a sample of 394 participants who were at least 60 years of age (138 male and 256 female). We also administered the Mini-Mental State Examination (MMSE) and the Center for Epidemiologic Studies for Depression (CES-D) scale. A multiple logistic regression analysis, which included SMC in association with the MMSE or CES-D scores and other confounding factors, was performed to determine the influence of sex on SMC. A P-value < 0.05 was considered statistically significant.

RESULTS

The durations of education of male participants were significantly higher than those of female participants. MMSE scores for female participants were significantly higher than those for male participants. There was no significant difference in CES-D scores between male and female participants. Twenty-four male participants and 72 female participants showed evidence of SMC. The incidence of SMC was more frequent in female participants than in male participants. In all participants, sex difference and CES-D score were significantly associated with SMC. In male participants, MMSE score was independently and significantly associated with SMC. Both in female participants and all participants, CES-D score was independently and significantly associated with SMC.

CONCLUSION

SMC varied by sex and were associated with the degree of cognitive impairment in male participants, while they were associated with depressive symptoms in female participants.

Affect and Memory in Real Life

Negative affect caused by depression is known to produce cognitive failures during everyday activities. However, traditional neurobehavioral laboratory paradigms that assess affect-memory interactions are critical with respect to their ecological validity. To investigate the effects of negative affect on memory processes in everyday life, we applied a new interactive measurement method in order to detect heart rate increases without accompanying physical activity and to initiate stimulus presentations depending on the specific emotional state in healthy participants. Psychophysiological instability and the intensity of psychophysiological arousal at the time of encoding proved to be important predictors of memory performance in negatively valenced situations. We suggest that multimodal ambulatory methods provide an interesting new opportunity for assessing interactions of emotion and cognition in real life.

Memory aging and brain maintenance

Episodic memory and working memory decline with advancing age. Nevertheless, large-scale population-based studies document well-preserved memory functioning in some older individuals. The influential ‘reserve’ notion holds that individual differences in brain characteristics or in the manner people process tasks allow some individuals to cope better than others with brain pathology and hence show preserved memory performance. Here, we discuss a complementary concept, that of brain maintenance (or relative lack of brain pathology), and argue that it constitutes the primary determinant of successful memory aging. We discuss evidence for brain maintenance at different levels: cellular, neurochemical, gray- and white-matter integrity, and systems-level activation patterns. Various genetic and lifestyle factors support brain maintenance in aging and interventions may be designed to promote maintenance of brain structure and function in late life.

Cognitive impairment in major depression and the mGlu2 receptor as a therapeutic target

Cognitive impairment, in particular of attention and memory, is often reported by patients suffering from major depressive disorder (MDD) and deficits in attention are part of the current diagnostic criteria of MDD. Objectively measured cognitive deficits associated with MDD have been described in many studies. They have been conceptualized as an integral facet and epiphenomenon of MDD. However, evidence accumulated in recent years has challenged this notion and demonstrated that in a subset of patients the degree of cognitive deficits cannot be accounted for by the severity of depression. In addition, in some patients cognitive deficits persist despite resolution of depressive symptomatology. It is plausible to assume that cognitive deficits contribute to functional impairment even though supportive data for such a relationship are lacking. However, the exact association between cognitive deficits and major depression and the clinical and neurobiological characteristics of patients with MDD in whom cognitive deficits seem partially or fully independent of the clinical manifestation of depressive symptoms remain poorly understood. This review focuses on objective measures of non-emotional cognitive deficits in MDD and discusses the presence of a subgroup of patients in whom these symptoms can be defined independently and in dissociation from the rest of the depressive symptomatology. The current understanding of brain circuits and molecular events implicated in cognitive impairment in MDD are discussed with an emphasis on the missing elements that could further define the specificity of cognitive impairment in MDD and lead to new therapeutics. Furthermore, this article presents in detail observations made in behavioral studies in rodents with potential novel therapeutic agents, such as negative allosteric modulators at the metabotropic glutamate receptor type 2/3 (mGlu2/3 NAM) which exhibit both cognitive enhancing and antidepressant properties. Such a compound, RO4432717, was tested in tests of short term memory (delayed match to position), cognitive flexibility (Morris water maze, reversal protocol), impulsivity and compulsivity (5-choice serial reaction time) and spontaneous object recognition in rodents, providing first evidence of a profile potentially relevant to address cognitive impairment in MDD. This article is part of a Special Issue entitled 'Cognitive Enhancers'.

What Do Cognitive Complaints in a Sample of Memory Clinic Outpatients Reflect?

Conflicting evidence exists concerning the value of cognitive complaints in the course of assessing cognitive performance in individuals. The present study examines whether cognitive complaints are differentially related to cognitive functioning in groups with different diagnoses. 169 older outpatients (76 years on average) were divided into three groups and diagnosed with subjective cognitive complaints, mild cognitive impairment, or dementia. They were then administered a self-rating questionnaire on cognitive complaints, with semantic fluency and global cognitive functioning being assessed as cognitive measures. Multiple regression analyses revealed that, after controlling for depression, age, sex, and education, global cognitive functioning was not related to cognitive complaints. Semantic fluency was related to cognitive complaints depending on the group. Results suggest that cognitive complaints reflect, in part, actual cognitive performance.

Is the lack of association between cognitive complaints and objective cognitive functioning in patients with bipolar disorder moderated by depressive symptoms?

OBJECTIVES

To investigate the association between cognitive complaints and objective cognitive functioning in bipolar patients, with a focus on the moderating role of depressive symptoms.

METHODS

The association between cognitive complaints (measured by the total score and four subscales of the Cognitive Failure Questionnaire; CFQ) and objective cognitive functioning (domains of psychomotor speed, speed of information processing, attentional switching, verbal memory, visual memory and executive functioning/working memory, and the total score) was assessed in 108 euthymic (n=45) or mildly to moderately depressed bipolar patients (n=63). We studied potential moderation of this association by depressive symptoms (total score of the Inventory of Depressive Symptomatology-self rating). Analyses were performed using Pearson correlations and multiple linear regression.

RESULTS

Cognitive complaints were not associated with objective cognitive functioning, except for CFQ 'memory for names' which was positively correlated with speed of information processing (r=0.257, p=0.007). Although depressive symptoms were positively associated with cognitive complaints (total score and three subscales; p<0.01), the association between cognitive complaints and objective cognitive functioning was not moderated by depressive symptoms (p for interaction 0.054 to 0.988).

LIMITATIONS

It can be argued whether the retrospective questionnaire (CFQ) is sufficiently accurate to measure the type of cognitive dysfunctions seen in bipolar patients.

CONCLUSIONS

Cognitive complaints are not associated with objective cognitive functioning, irrespective of depressive symptoms. However, cognitive complaints are indicative for depressive symptoms. Clinicians should be to be alert to depressive symptoms rather than objective cognitive problems in patients expressing cognitive complaints.

The impact of neutral and emotionally negative distraction on memory performance and its relation to memory complaints in major depression

Patients with major depression (MDD) often report relevant cognitive problems in everyday life while performance in standardised neuropsychological tests is not severely disturbed. This discrepancy may partly be due to the differences between the demands of everyday life with the presence of emotionally relevant distractors and standardised neuropsychological settings without those distractors. In the present study, we hypothesise that patients with major depression (MDD) show an increased distractibility towards emotionally negative stimuli and that this distractibility is related to complaints of cognitive functioning in everyday life. Thirty MDD patients and 48 healthy participants performed our recently developed learning paradigm with neutrally and negatively valenced distraction as well as without distraction. Both groups also performed a neuropsychological test battery as well as self- and observer ratings of impairments in memory and attention in every day life. In the MDD sample, cognitive impairments were reported by the patients and their relatives but were not found in the neuropsychological tests. We found a trend towards a poorer memory performance with negatively valenced distraction in the MDD sample when compared to the performance of healthy subjects. However, this impairment was not related to the self- and observer ratings. This result may be due to the fact that the distractors were not personally relevant to the subjects whereas everyday life implies such distractors. Further research is needed to explore everyday cognitive functioning of patients with MDD.

Entwicklung eines Fragebogens zur subjektiven Einschätzung der geistigen Leistungsfähigkeit (FLei) bei Patienten mit psychischen Störungen

Das Ziel dieser Untersuchung besteht in einer ersten Überprüfung der testtheoretischen Kennwerte des neu entwickelten «Fragebogens zur geistigen Leistungsfähigkeit (FLei)» bei Patienten mit psychischen Störungen. An der Untersuchung nahmen insgesamt 259 Personen teil, 68 Schizophreniepatienten, 94 depressive Patienten und 97 Kontrollpersonen. Die ursprüngliche Version des Fragebogens umfasste 88 Items der Bereiche Aufmerksamkeit, Gedächtnis und Exekutivfunktionen sowie Fragen zum visuellen Neglekt. Der Fragebogen konnte auf 35 Items reduziert werden. Items verschiedener Funktionsbereiche waren hoch miteinander korreliert. Itemkennwerte, interne Konsistenz und Split-Half Reliabilität sind durchgängig als gut zu bezeichnen. Depressive Patienten berichteten die deutlichsten Defizite. Eine funktionsspezifische Auswertung ist aufgrund der hohen Interkorrelationen zwischen den Funktionsbereichen nur bedingt zu empfehlen. In weiteren Untersuchungen sollten die Ergebnisse an einer unabhängigen Stichprobe bestätigt werden.

Memory complaints to the general practitioner: data from the GuidAge study

Memory complaints are relatively common in elderly people, although they are not always reported to the general practitioner (GP). These subjective complaints do not necessarily correlate with objective measures of memory impairment or cognitive performance, but they may be an early indication of impairment at a state that is undetectable by standard testing instruments. Memory complaints may also predict future cognitive decline. The GuidAge study is a secondary prevention trial for Alzheimer's disease involving non-demented individuals aged 70 years or older having spontaneously complained of memory problems to their GP. More than half of participants had a Clinical Dementia Rating score of 0.5 at baseline. The percentage of participants reporting problems on the McNair and Kahn scale varied from 6.2% to 78.6% per item. Certain specific memory complaints may be more related than others to the beginning of the neurodegenerative process, and could predict future cognitive decline. The importance of memory complaints should not be underestimated in clinical practice.