The relationship of recency discrimination to explicit memory and executive functioning.

Recency discrimination has been conceptualized as an executive ability by some investigators and as an aspect of episodic memory by others. We compared the performance of 261 neurologically healthy adults on a recency discrimination task (RDT) with their performance on measures of executive functioning and explicit memory. Mean z-transformed raw scores were used to construct indices of visual and verbal explicit memory, fluency, and executive functioning. Analyses revealed that RDT performance correlated more closely with visual (r = 0.32; p < 0.001) and verbal memory (r = 0.25; p < 0.001) than with fluency (r = 0.16; p < 0.05) and executive functioning (r = 0.13; p < 0.05). These findings suggest that recency discrimination might be better understood as an aspect of episodic memory that is subserved primarily by hippocampal and medial temporal structures than as an executive function that is subserved primarily by prefrontal cortex.     

Executive function mediates effects of white matter hyperintensities on episodic memory

This study examined the relationship between white matter hyperintensities (WMH) and executive functioning on episodic memory in a group of older adults who were cognitively normal or diagnosed with MCI or dementia. Volumetric magnetic resonance imaging (MRI) measures of total brain volume, white matter hyperintensity volume, and hippocampal volume along with age, education, and gender were evaluated as predictors of episodic memory. WMH were found to influence both episodic memory and executive functioning independently of other variables. The influence WMH on episodic memory was mediated by executive functioning and was completely eliminated when the interaction between executive functioning and hippocampal volume was entered in the regression model. The results indicate that executive functioning mediates the effects of WMH on episodic memory but that executive functioning and hippocampal volume can also interact such that executive functioning can exacerbate or ameliorate the influence of hippocampal volume on episodic memory.     

The Key Behaviors Change Inventory and Executive Functioning in an Elderly Clinic Sample

The Key Behaviors Change Inventory (KBCI) was developed to assess executive, behavioral, and emotional functioning following brain insults and to track the course of recovery. The purpose of this study was to investigate, in an elderly memory disorder clinic sample, the convergent and discriminant validity of the KBCI by examining the relationships between various measures of executive functioning and the KBCI scales that theoretically relate to executive functions. The KBCI was administered to the caregivers of 97 consecutive patients who came to a memory disorders clinic seeking services. The KBCI scales of Inattention, Apathy, Unawareness of Problems, and Communication Problems were significantly correlated with cognitive measures of executive functioning but not with measures of memory, visuospatial abilities or global cognitive functioning. In contrast, KBCI scales of Interpersonal Difficulties, Somatic Difficulties, and Emotional Adjustment were not related to any cognitive measures, either executive or nonexecutive. Contrary to predicted findings, the Impulsivity Scale was not associated with cognitive measures of executive functioning. This lack of relationship most likely reflects the failure to include executive measures of orbitofrontal functioning in this study. Results provide convergent and discriminant validity support for the KBCI. The KBCI may be a useful tool for assessing and tracking the executive, behavioral, and emotional sequelae of neurologic disorders.     

The Key Behaviors Change Inventory and executive functioning in an elderly clinic sample

The Key Behaviors Change Inventory (KBCI) was developed to assess executive, behavioral, and emotional functioning following brain insults and to track the course of recovery. The purpose of this study was to investigate, in an elderly memory disorder clinic sample, the convergent and discriminant validity of the KBCI by examining the relationships between various measures of executive functioning and the KBCI scales that theoretically relate to executive functions. The KBCI was administered to the caregivers of 97 consecutive patients who came to a memory disorders clinic seeking services. The KBCI scales of Inattention, Apathy, Unawareness of Problems, and Communication Problems were significantly correlated with cognitive measures of executive functioning but not with measures of memory, visuospatial abilities or global cognitive functioning. In contrast, KBCI scales of Interpersonal Difficulties, Somatic Difficulties, and Emotional Adjustment were not related to any cognitive measures, either executive or nonexecutive. Contrary to predicted findings, the Impulsivity Scale was not associated with cognitive measures of executive functioning. This lack of relationship most likely reflects the failure to include executive measures of orbitofrontal functioning in this study. Results provide convergent and discriminant validity support for the KBCI. The KBCI may be a useful tool for assessing and tracking the executive, behavioral, and emotional sequelae of neurologic disorders.     

The Boston Qualitative Scoring System as a measure of executive functioning in Rey-Osterrieth Complex Figure performance

The Boston Qualitative Scoring System (BQSS) for the Rey-Osterrieth Complex Figure (ROCF) includes five scores (Planning, Fragmentation, Neatness, Perseveration, and Organization) developed to measure the executive aspects of ROCF productions. To assess the convergent and discriminant validity of the BQSS, these five scores were compared to scores on four traditional tests of executive functioning, as well as to three non-executive measures, in 141 adult patients. BQSS executive variables significantly correlated with the traditional executive measures and were less correlated with discriminant measures. The BQSS Organization summary score also significantly differentiated patients with either no, mild, or severe executive dysfunction. These results support the construct validity of the BQSS and demonstrate that the ROCF may be a useful measure of executive functioning.     

The Boston Qualitative Scoring System as a Measure of Executive Functioning in Rey-Osterrieth Complex Figure Performance

The Boston Qualitative Scoring System (BQSS) for the Rey-Osterrieth Complex Figure (ROCF) includes five scores (Planning, Fragmentation, Neatness, Perseveration, and Organization) developed to measure the executive aspects of ROCF productions. To assess the convergent and discriminant validity of the BQSS, these five scores were compared to scores on four traditional tests of executive functioning, as well as to three non-executive measures, in 141 adult patients. BQSS executive variables significantly correlated with the traditional executive measures and were less correlated with discriminant measures. The BQSS Organization summary score also significantly differentiated patients with either no, mild, or severe executive dysfunction. These results support the construct validity of the BQSS and demonstrate that the ROCF may be a useful measure of executive functioning.     

The contribution of executive functions deficits to impaired episodic memory in individuals with alcoholism

Individuals with alcoholism commonly exhibit impaired performance on episodic memory tasks. However, the contribution of their impaired executive functioning to poor episodic memory remains to be clarified. Thirty-six recently detoxified and sober asymptomatic alcoholic men and 36 matched non-alcoholic participants were tested for processing speed, prepotent response inhibition, mental flexibility, coordination of dual-task and a verbal episodic memory task. Compared with non-alcoholic individuals, the alcoholic patients showed impaired executive functions combined with below normal performance on both free and delayed recall. In contrast, processing speed, cued recall and recognition were preserved. Regression analyses revealed that 47% of alcoholics' episodic memory's free recall performance was predicted by mental flexibility and that 49% of their delayed recall performance was predicted by mental flexibility, manipulation of dual-task and prepotent response inhibition. Regarding participants' executive predictors of episodic memory performance, the slopes of β coefficients were significantly different between the two groups, with alcoholics requiring more their executive system than non-alcoholics. Once detoxified, alcoholic patients showed episodic memory deficits mainly characterized by impaired effortful (executive) processes. Compared with controls, patients used effortful learning strategies, which are nonetheless less efficient.     

Recognition of faces and names: multimodal physiological correlates of memory and executive function

We sought to characterize electrophysiological, eye-tracking and behavioral correlates of face-name recognition memory in healthy younger adults using high-density electroencephalography (EEG), infrared eye-tracking (ET), and neuropsychological measures. Twenty-one participants first studied 40 face-name (FN) pairs; 20 were presented four times (4R) and 20 were shown once (1R). Recognition memory was assessed by asking participants to make old/new judgments for 80 FN pairs, of which half were previously studied items and half were novel FN pairs (N). Simultaneous EEG and ET recording were collected during recognition trials. Comparisons of event-related potentials (ERPs) for correctly identified FN pairs were compared across the three item types revealing classic ERP old/new effects including 1) relative positivity (1R > N) bi-frontally from 300 to 500 ms, reflecting enhanced familiarity, 2) relative positivity (4R > 1R and 4R > N) in parietal areas from 500 to 800 ms, reflecting enhanced recollection, and 3) late frontal effects (1R > N) from 1000 to 1800 ms in right frontal areas, reflecting post-retrieval monitoring. ET analysis also revealed significant differences in eye movements across conditions. Exploration of cross-modality relationships suggested associations between memory and executive function measures and the three ERP effects. Executive function measures were associated with several indicators of saccadic eye movements and fixations, which were also associated with all three ERP effects. This novel characterization of face-name recognition memory performance using simultaneous EEG and ET reproduced classic ERP and ET effects, supports the construct validity of the multimodal FN paradigm, and holds promise as an integrative tool to probe brain networks supporting memory and executive functioning.     

Factor Structure and Construct Validity of the Behavioral Dyscontrol Scale-II

The Behavioral Dyscontrol Scale-II (BDS-II) was developed as an improved scoring method to the original BDS, which was designed to evaluate the capacity for independent regulation of behavior and attention. The purpose of this study was to evaluate the factor structure and construct validity of the BDS-II, which had not been adequately re-examined since the development of the new scoring system. In a sample of 164 Veterans with a mean age of 35 years, exploratory factor analysis was used to evaluate BDS-II latent factor structure. Correlations and regressions were used to explore validity against 22 psychometrically sound neurocognitive measures across seven neurocognitive domains of sensation, motor output, processing speed, attention, visual-spatial reasoning, memory, and executive functions. Factor analysis found a two-factor solution for this sample which explained 41% of the variance in the model. Validity analyses found significant correlations among the BDS-II scores and all other cognitive domains except sensation and language (which was not evaluated). Hierarchical regressions revealed that PASAT performance was strongly associated with all three BDS-II scores; dominant hand Finger Tapping Test was also associated with the Total score and Factor 1, and CPT-II Commissions was also associated with Factor 2. These results suggest the BDS-II is both a general test of cerebral functioning, and a more specific test of working memory, motor output, and impulsivity. The BDS-II may therefore show utility with younger populations for measuring frontal lobe abilities and might be very sensitive to neurological injury.     

Episodic memory and neuroimaging of hippocampus and fornix in chronic schizophrenia

A group of 44 patients with schizophrenia and 43 age-matched controls completed psychometrically-matched tasks of recall and recognition. The patients showed similarly depressed scores across both recall and recognition matched tasks, independent of their reduced IQ and executive functioning scores. In addition, reduced memory scores correlated in the expected direction with magnetic resonance imaging (MRI) of the hippocampus and diffusion tension imaging (DTI) of the fornix for subsets of both patients and controls that had available these structural imaging measures. Reduced executive functioning also correlated with lower fornix integrity for the patient subset. However, increased hippocampal volume correlated, in the negative direction, with lower scores for executive functioning and IQ in the control subset. Implications of these results are discussed.     

Mechanism of disorientation in Alzheimer's disease

In nondemented amnesics, disorientation mostly reflects a failure to select memories that pertain to ongoing reality (increased temporal context confusion; TCC), a failure strongly associated with orbitofrontal damage. In the present study, we used the same paradigm--2 runs of a continuous recognition task--in 23 patients with mild to moderate Alzheimer's disease (AD) (Clinical Dementia Rating Scale score of 1-2). We found that disorientation was frequent in this sample (52%). However, although it correlated moderately well with general measures of dementia severity, verbal episodic memory and executive functioning, there was no significant correlation with TCC. Thus, disorientation in AD appears to reflect general cognitive decline rather than a specific cognitive failure such as increased TCC. This finding is compatible with the different distribution of degeneration in AD and the orbitofrontal damage typically present in severely disoriented amnesics.     

Cognitive estimation in traumatic brain injury.

The present study explores the construct and ecological validity of the Biber Cognitive Estimation Test (BCET) in a traumatic brain injury (TBI) sample. Participants completed the BCET in the course of a neuropsychological evaluation at 1-15 years after injury. BCET scores correlated moderately with other standard measures of executive functioning, and contrary to our hypotheses, at least as high with neuropsychological tests with minimal demands on executive functioning. Moreover, partialing out the portion of BCET variance not attributable to executive functioning markedly attenuated the former correlations. With respect to ecological validity, BCET scores did not predict concurrent functional status, as measured by the Disability Rating Scale. By comparison, standard measures of executive functioning strongly correlated with each other, correlated less strongly with nonexecutive functioning measures, and predicted functional status. In conclusion, unlike standard measures of executive functioning, the BCET demonstrated poor construct and ecological validity in TBI patients.     

Investigating whether depressed youth exhibiting elevated C reactive protein perform worse on measures of executive functioning,verbal fluency and episodic memory in a large,population based sample of Dutch adolescents

Cognitive functioning is disrupted during a depressive episode and cognitive dysfunction persists when depression is in remission. A subtype of depressed individuals who exhibit elevated inflammatory biomarkers may be at particular risk for cognitive dysfunction. We examined whether an elevated inflammatory biomarker (C-reactive protein: CRP) in acute and/or remitted depression was associated with specific deficits in executive functioning, episodic memory, and verbal fluency. Data were drawn from a population-based sample of Dutch adolescents (N = 1066; 46% male) recruited at the age of 11 and followed over the course of eight years. We tested whether adolescents with either, (i) a history of depression (Wave 1–3) or (ii) current depression (Wave 4), and elevated levels of C-reactive protein measured in blood at Wave 3 performed worse on cognitive assessments at Wave 4. Eight measures of cognitive functioning were hypothesized to load on to one of three dimensions of cognitive functioning (executive functioning, episodic memory, and verbal fluency) within a structural equation model framework. Higher levels of CRP were associated with worse future executive functioning in adolescents with and without current/prior depression. A current depression diagnosis also was associated with worse executive functioning. There was consistent evidence linking low socioeconomic status and health-related covariates (high body mass index/sedentary behavior) with worse performance across multiple measures of cognitive functioning and, importantly, the association of depression/CRP and executive functioning was no longer significant when controlling for these covariates. Future studies may benefit from investigating whether specific depressogenic behaviors (e.g., sedentary behavior/substance use) mediate a relationship between depression and worse executive functioning, potentially via a prospective pathway through elevated inflammation.     

The role of decision-making ability in HIV/AIDS: Impact on prospective memory

Background: Prospective memory (ProM), a form of episodic memory related to execution of future intentions, is important for everyday functioning. Among persons living with HIV (PLWH), executive dysfunction is implicated in ProM impairments. However, specific subcomponents of executive functioning involved in ProM deficits remain poorly understood. Unlike more “traditional” neurocognitive (NC) measures of executive functioning associated with dorsolateral prefrontal cortex (i.e., conceptual reasoning, abstraction), those associated with medial orbitofrontal/ventromedial prefrontal (mOF/vmP) cortex (i.e., decision making, inhibitory control, goal-oriented behavior) have yet to be examined in ProM. Method: This study characterized ProM ability in a sample of 89 HIV-seropositive adults and examined the unique role of decision-making ability in ProM. Participants completed a standard NC battery, the Iowa Gambling Task (IGT; a decision-making measure), and the Memory for Intentions Screening Test (MIST; a ProM measure). Results: Correlational analyses revealed that both traditional executive functioning measures and the IGT were associated with ProM. Regression analyses revealed that the IGT significantly predicted ProM, even after accounting for NC measures. Among all NC measures, only executive functioning significantly contributed to ProM. Discussion: Further examination of mOF/vmP-sensitive executive dysfunction within this population is needed as PLWH may require more tailored treatment recommendations due to specific decision-making difficulties that can impact medication management.     

帕金森病患者记忆监测与情景记忆的相关研究

目的 研究帕金森病患者( Parkinson's disease,PD)对情景记忆监测情况,并进一步探讨PD患者情景记忆障碍的可能机制.方法 建立情景记忆知晓感(feeling of knowing-episodic memory,FOK-EM)判断的试验范式,对25例PD患者和25名年龄及教育程度相匹配的健康对照(HC)者进行研究.结果 与HC组的FOK-EM的回忆率(39.67％±6.11％)、再认率(58.42％±7.50％)以及FOK判断准确率(0.61 ±0.22)比较,PD患者组FOK-EM的回忆率(19.33％±5.10％)、再认率(45.93％±7.82％)以及FOK判断准确率(-0.18±0.46)显著降低,差异均有统计学意义(t=-4.833,P＜0.01;t=-2.497,P＜0.05;t=-5.986,P＜0.01);FOK-EM的肯定判断/正确再认成绩(20.47％±10.78％)以及肯定判断/错误再认成绩(即高估,29.53％±5.62％)与HC组的肯定判断/正确再认成绩(39.47％±9.47％)以及肯定判断/错误再认成绩(即高估,13.90％±5.50％)之间差异有统计学意义(t =3.564,P＜0.05;t=2.306,P＜0.05),且Stroop效应与FOK-EM的肯定判断/错误再认成绩呈正相关(r =0.640,P＜0.01).结论 PD患者的情景记忆监测受损,表现为对自身再认能力的高估.这种记忆监测受损与执行功能的损害相关,提示此机制可能是导致PD患者情景记忆障碍的重要因素.     

Episodic and semantic memory in mild cognitive impairment

Little is known about episodic and semantic memory in the early predementia stage of Alzheimer's disease (AD), which is referred to as mild cognitive impairment (MCI). To explore person knowledge, item recognition and spatial associative memory, we designed the Face Place Test (FPT). A total of 75 subjects participated: 22 patients with early AD, 24 with MCI and 29 matched controls. As predicted, AD patients showed significant deficits in person naming, item recognition and recall of spatial location (placing). Surprisingly, subjects with MCI were also impaired on all components. There was no significant difference between AD and MCI except on the placing component. Analysis of the relationship between semantic (naming) and episodic (recognition and placing) components of the FPT revealed a significant association between the two episodic tasks, but not between episodic and semantic performance. Patients with MCI show deficits of episodic and semantic memory. The extent of impairment suggests dysfunction beyond the medial temporal lobe. The FPT might form the basis of a sensitive early indicator of AD.     

Treatment of cognitive impairment in early psychosis: a comparison of risperidone and haloperidol in a large long-term trial

OBJECTIVE: Cognitive impairment is a major determinant of functional outcome in schizophrenia. Treatment of cognitive impairment at the time of the first episode may have the potential to change functional outcomes of the illness. This study examined changes associated with treatment with risperidone compared with haloperidol in aspects of cognitive functioning known to be associated with functional outcomes. The study was conducted in a large group of patients experiencing their first episode of schizophrenia. METHOD: Cognitive assessments were conducted in 533 patients experiencing their first episode of schizophrenia or a related psychosis who had been randomly assigned to receive low doses of risperidone or haloperidol. The cognitive assessments were repeated at several different follow-up intervals; 359 patients were reexamined at the 3-month follow-up. The assessments included examinations of verbal and visuospatial episodic memory, vigilance, executive functioning, processing speed, and verbal fluency. Patients' clinical symptoms were also rated with the Positive and Negative Syndrome Scale. RESULTS: Improvements from baseline were found in the risperidone-treated patients for episodic memory, verbal fluency, vigilance, executive functioning, and visuomotor speed. Haloperidol-treated patients also showed improvements from baseline in episodic memory, vigilance, and visuomotor speed but not in executive functioning or verbal fluency. Comparison of differential treatment effects on a composite measure of cognitive functioning found that risperidone was significantly more beneficial than haloperidol after 3 months of treatment. Changes in Positive and Negative Syndrome Scale scores were correlated overall with improvement in the haloperidol-treated patients but not in the risperidone-treated patients. CONCLUSIONS: Treatment with risperidone at the time of the first episode of schizophrenia is associated with wide-ranging improvements in cognitive functioning. Overall improvement is significantly greater with risperidone than with haloperidol. Further, cognitive improvement associated with treatment with risperidone was not influenced by changes in symptoms, but that relationship was significant in haloperidol-treated patients.     

Metamemory monitoring in mild cognitive impairment: Evidence of a less accurate episodic feeling-of-knowing

This study aimed at exploring metamemory and specifically the accuracy of memory monitoring in mild cognitive impairment (MCI) using an episodic memory feeling-of-knowing (FOK) procedure. To this end, 20 people with MCI and 20 matched control participants were compared on the episodic FOK task. Results showed that the MCI group made less accurate FOK predictions than the control group by overestimating their memory performance on a recognition task. The MCI overestimation behavior was found to be critically related to the severity of their cognitive decline. In the light of recent neuroanatomical models showing the involvement of a temporal-frontal network underlying accurate FOK predictions, the role of memory and executive processes was evaluated. Thus, participants were also administered memory and executive neuropsychological tests. Correlation analysis revealed a between-group differential pattern indicating that FOK accuracy was primarily related to memory abilities in people with MCI, whereas it was specifically related to executive functioning in control participants. The lesser ability of people with MCI to assess their memory status accurately on an episodic FOK task is discussed in relation to both their subjective memory complaints and to their actual memory deficits which might be mediated by the brain vulnerability of their hippocampus and medial temporal system. It is suggested that their memory weakness may lead people with MCI to use other less reliable forms of memory monitoring.     

Action (verb naming) fluency as an executive function measure: convergent and divergent evidence of validity

Numerous studies have demonstrated dissociable neuroanatomic underpinnings for the retrieval of grammatical classes of words such as nouns and verbs. Whereas retrieval of common and proper nouns is primarily mediated by posterior and anterior temporal regions, respectively, verb retrieval is primarily mediated by frontal regions. The majority of studies evaluating verb production have utilized tasks requiring subjects to name a graphically depicted action (i.e. action naming), leaving tests of verb generation in the absence of prompting stimuli (i.e. action fluency) largely unexamined. In a recent study, Piatt, Fields, Paolo, Koller and Tröster (in press) found that an action fluency task discriminated demented Parkinson’s disease (PD) patients from non-demented PD patients and healthy control subjects, whereas lexical and categorical fluency tasks did not. These authors suggested that action fluency was sensitive to the fronto–striatal pathophysiology associated with PD dementia, and thus, that action fluency might serve as an indicator of executive functioning. This study was undertaken to evaluate the construct validity of action fluency as an executive function measure in a group of healthy elderly control subjects. Findings revealed modest to moderate relationships between action fluency and several putative executive measures. Action fluency was unrelated to indices of semantic and episodic memory. Results support the construct validity of action fluency as an executive function measure and suggest that this task may provide some unique information not tapped by traditional executive function tasks.     

Emotional intelligence and social functioning in persons with schizotypy

The present study is the first to examine emotional intelligence in persons with schizotypy. Over 2100 undergraduates were screened for schizotypy with the Schizotypal Personality Questionnaire - Brief Version. Forty participants identified as persons with high schizotypy and 56 participants identified as persons with low schizotypy completed assessments of emotional intelligence (Mayer-Salovey-Caruso Emotional Intelligence Test), social functioning (Social Adjustment Scale - Self Report), verbal episodic (secondary) memory (California Verbal Learning Test), and executive functioning (Wisconsin Card Sorting Test). Persons high in schizotypy were impaired in overall emotional intelligence and two aspects of emotional intelligence, the ability to perceive emotions and the ability to manage emotions. Persons high in schizotypy were also impaired in three aspects of social functioning: peer relationships, family relationships, and academic functioning. Group differences in verbal episodic (secondary) memory and executive functioning were not observed. For persons with high schizotypy, overall emotional intelligence and two aspects of emotional intelligence, the ability to perceive emotions and the ability to manage emotions, were associated with peer relationship functioning. Overall emotional intelligence was associated with verbal episodic (secondary) memory, but not executive functioning, in persons with high schizotypy. The current findings suggest that emotional intelligence is impaired in persons with schizotypy and that these impairments affect their social functioning.