Many studies have assessed visual short-term memory (VSTM) abilities in children with specific language impairment (SLI), with contrasting results: some studies observed preserved VSTM capacities, while others reported impaired VSTM. The present study explores the hypothesis that the complexity of the visual information to be encoded and stored might underlie these discrepancies. Four VSTM conditions were administered to a group of 15 children with SLI, as well as to two groups of typically developing children, matched for chronological age and for VSTM capacity for visually simple stimuli, respectively. The stimuli to be remembered varied in their visual similarity and in the number of their visual features. Across the four VSTM conditions, children with SLI showed significantly reduced performance relative to an age-matched control group, and they were more strongly affected by visual similarity and number of features when compared to a control group matched for VSTM capacity for visually simple stimuli. The present results support the hypothesis that stimulus complexity is a determining factor of the poor VSTM performances in children with SLI. (JINS, 2012, 18, 501–510)

Despite the prevalence of HIV-associated episodic memory impairment and its adverse functional impact, there are no empirically validated cognitive rehabilitation strategies for HIV-infected persons. The present study examined the self-generation approach, which is theorized to enhance new learning by elaborating and deepening encoding. Participants included 54 HIV-infected and 46 seronegative individuals, who learned paired word associates in both self-generated and didactic encoding experimental conditions. Results revealed main effects of HIV serostatus and encoding condition, but no interaction. Planned comparisons showed that both groups recalled significantly more words learned in the self-generation condition, and that HIV+ individuals recalled fewer words overall compared to their seronegative counterparts at delayed recall. Importantly, HIV+ participants with clinical memory impairment evidenced similar benefits of self-generation compared to unimpaired HIV+ subjects. Self-generation strategies may improve verbal recall in individuals with HIV infection and may, therefore, be an appropriate and potentially effective cognitive rehabilitation tool in this population. (JINS, 2012, 18, 128–133)

Difficulties related to inhibition and set-shifting have been suggested as possible endophenotypes of Attention Deficit Hyperactivity Disorder (ADHD). However, such difficulties have not been consistently found in studies using standard neuropsychological tests. This has been partly explained by the complexity of these tests and the need to include contrast measures which control for more basic functions. The purpose of the present study was to examine whether difficulties related to inhibition and set-shifting in adult ADHD patients could be revealed by the Color Word Interference Test (CWIT) from the Delis Kaplan Executive Function System (D-KEFS). A clinically recruited group of adults with ADHD (n = 60) obtained significantly lower scores than population derived controls (n = 60) on both primary summary (p < .001) and contrast measures (p = .004) of set-shifting. The differences between the groups remained statistically significant after controlling for intellectual function and working memory (p = .003). However, no significant differences between the groups were observed on any measure of inhibition. The study indicates that adults with ADHD have specific difficulties with set-shifting as measured by the CWIT, difficulties that probably also reflect problems related to executive function in their daily life. (JINS, 2012, 18, 1–10)

Theory of mind (ToM) involves thinking about mental states and intentions to understand what other people know and to predict how they will act. We studied ToM in children with traumatic brain injury (TBI) and age- and gender-matched children with orthopedic injuries (OI), using a new three-frame Jack and Jill cartoon task that measures intentional thinking separate from contingent task demands. In the key ToM trials, which required intentional thinking, Jack switched a black ball from one hat to another of a different color, but Jill did not witness the switch; in the otherwise identical non-ToM trials, the switch was witnessed. Overall accuracy was higher in children with OI than in those with TBI. Children with severe TBI showed a larger decline in accuracy on ToM trials, suggesting a specific deficit in ToM among children with severe TBI. Accuracy was significantly higher on trials following errors than on trials following correct responses, suggesting that all groups monitored performance and responded to errors with increased vigilance. TBI is associated with poorer intentional processing in school-age children and adolescents relative to peers with OI; furthermore, children with TBI are challenged specifically by intentional demands, especially when their injury is severe. (JINS, 2012, 19, 1–9)

In randomized clinical trials of aphasia treatment, a functional outcome measure like the Amsterdam-Nijmegen Everyday Language Test (ANELT), administered by speech-language therapists, is often used. However, the agreement between this expert rating and the judgment of the proxy about the quality of the daily life communication of the person with aphasia is largely unknown. We examined the association between ANELT scores by speech-language therapists and proxy judgments on the Partner Communication Questionnaire both at 3 and 6 months in 39 people with aphasia after stroke. We also determined which factors affected the level of agreement between expert and proxy judgment of the communicative ability at 6 months in 53 people with aphasia. We found moderate agreement (at 3 months r = .662; p = < .0001 and at 6 months r = .565; p = .0001), with proxies rating slightly higher than experts. Less severe aphasia, measured with the Aphasia Severity Rating Scale, was associated with better agreement. In conclusion, although proxies were slightly more positive than experts, we found moderate agreement between expert and proxy rating of verbal communicative ability of people with aphasia after stroke, especially in milder cases. (JINS, 2012, 18, 1064–1070)

Recent research has established that individuals with amnestic mild cognitive impairment (aMCI) have impaired prospective memory (PM); however, findings regarding differential deficits on time-based versus event-based PM have been less clear. Furthermore, the diagnostic utility of PM measures has received scant attention. Healthy older adults (n = 84) and individuals with aMCI (n = 84) were compared on the Cambridge Prospective Memory Test (CAMPROMPT) and two single-trial event-based PM tasks. The aMCI participants showed global impairment on all PM measures. Measures of retrospective memory and complex attention predicted both time and event PM performance for the aMCI group. Each of the PM measures was useful for discriminating aMCI from healthy older adults and the time- and event-based scales of the CAMPROMPT were equivalent in their discriminative ability. Surprisingly, the brief PM tasks were as good as more comprehensive measures of PM (CAMPROMPT) at predicting aMCI. Results indicate that single-trial PM measures, easily integrated into clinical practice, may be useful screening tools for identifying aMCI. As PM requires retrospective memory skills along with complex attention and executive skills, the interaction between these skills may explain the global PM deficits in aMCI and the good discriminative ability of PM for diagnosing aMCI. (JINS, 2012, 18, 295–304)

Difficulty with selective attention is a frequent complaint of adult patients with ADHD, but selective attention tasks have not provided robust evidence of attentional dysfunction in this group. Two experiments examine this puzzle by distinguishing between failures of spatial selection and problems due to sensitivity to perceptual interference. In Experiment 1, we measured the level of perceptual interference generated by targets in crowded displays with nearby distractors by comparing luminance thresholds in both distractor-present (noise) and distractor-absent (clean) displays. ADHD and control participants had comparable thresholds for clean displays, but ADHD individuals had elevated thresholds to crowded displays. These effects could be explained in two distinct ways. Deficits may have arisen from amplified visual interference in the noise condition, or from abnormalities in top-down attentional processes that reduce visual interference. Experiment 2 adjusted for individual perceptual differences with clean and noise displays, before measuring visual interference resolution at attended versus unattended locations. ADHD and control groups had comparable interference resolution at attended locations. These results suggest that perceptual interference rather than spatial attention deficits may account for some deficits in ADHD. This putative deficit in sensory function highlights a potential early-stage perceptual processing deficit in ADHD distinct from selective attention. (JINS, 2012, 18, 511–520)

The present study aimed to examine if bilingualism affects executive functions and verbal fluency in Marathi and Hindi, two major languages in India, with a considerable cognate (e.g., activity is actividad in Spanish) overlap. A total of 174 native Marathi speakers from Pune, India, with varying levels of Hindi proficiency were administered tests of executive functioning and verbal performance in Marathi. A bilingualism index was generated using self-reported Hindi and Marathi proficiency. After controlling for demographic variables, the association between bilingualism and cognitive performance was examined. Degree of bilingualism predicted better performance on the switching (Color Trails-2) and inhibition (Stroop Color-Word) components of executive functioning; but not for the abstraction component (Halstead Category Test). In the verbal domain, bilingualism was more closely associated with noun generation (where the languages share many cognates) than verb generation (which are more disparate across these languages), as predicted. However, contrary to our hypothesis that the bilingualism “disadvantage” would be attenuated on noun generation, bilingualism was associated with an advantage on these measures. These findings suggest distinct patterns of bilingualism effects on cognition for this previously unexamined language pair, and that the rate of cognates may modulate the association between bilingualism and verbal performance on neuropsychological tests. (JINS, 2012, 18, 305–313)

Accurate measurement of cognitive function is critical for understanding the disease course of Alzheimer's disease (AD). Detecting cognitive change over time can be confounded by level of premorbid intellectual function or cognitive reserve and lead to under- or over-diagnosis of cognitive impairment and AD. Statistical models of cognitive performance that include cognitive reserve can improve sensitivity to change and clinical efficacy. We used confirmatory factor analysis to test a four-factor model composed of memory/language, processing speed/executive function, attention, and cognitive reserve factors in a group of cognitively healthy older adults and a group of participants along the spectrum of amnestic mild cognitive impairment to AD (aMCI-AD). The model showed excellent fit for the control group (χ2 = 100; df = 78; CFI = .962; RMSEA = .049) and adequate fit for the aMCI-AD group (χ2 = 1750; df = 78; CFI = .932; RMSEA = .085). Although strict invariance criteria were not met, invariance testing to determine if factor structures are similar across groups yielded acceptable absolute model fits and provide evidence in support of configural, metric, and scalar invariance. These results provide further support for the construct validity of cognitive reserve in healthy and memory impaired older adults. (JINS, 2012, 18, 1–10)

Memory problems are common in patients with a range of neurological conditions, but there have been few attempts to provide and evaluate the usefulness of memory training for groups of neurological outpatients. We used a waitlist-controlled trial design to assess the effectiveness of a newly created, 6-session intervention, which involved training in the use of compensatory strategies as well as education regarding memory function, neurological damage, sleep and lifestyle factors that have an impact on memory. Fifty-six patients with neurological conditions (e.g., stroke, epilepsy) and memory complaints completed the training and assessments. Outcomes were evaluated in terms of reported strategy use as well as objective and subjective measures of anterograde and prospective memory. Training resulted in significant improvements on number of strategies used, scores on the Rey Auditory Verbal Learning Test (total learning and delayed recall) and self-report on the Comprehensive Assessment of Prospective Memory. Improvements were stable at 3-month follow-up. Better individual outcomes were related to lower baseline memory scores, fewer symptoms of depression and greater self-awareness of memory function. Overall the study provides encouraging results to indicate that patients with neurological conditions such as stroke and epilepsy can show improvements in memory after a relatively short group-based intervention. (JINS, 2012, 18, 1–11)

Moderate declines in prospective memory (PM) are common among older adults, but whether such decrements are associated with everyday functioning problems is not well established. To examine this issue, we administered the Memory for Intentions Screening Test (MIST), Prospective and Retrospective Memory Questionnaire (PRMQ), and Activities of Daily Living Questionnaire (ADLQ) to 50 healthy older Australian adults as part of a broader neuropsychological battery. In a series of hierarchical regressions controlling for demographics, medical/psychiatric factors, and other neurocognitive functions, the MIST event-based PM score and PRMQ PM scale were significantly associated with the total number of instrumental ADL (IADL) domains in which participants reported needing assistance. Extending prior findings in clinical populations, results indicate that lower PM functioning is uniquely associated with mild, concurrent IADL problems in healthy older adults. Future investigation of the potentially moderating effects of cognitive and behavioral compensatory strategies may be beneficial. (JINS, 2012, 18, 134–138)

Combat veterans with post-traumatic stress disorder (PTSD) can show impairments in executive control and increases in impulsivity. The current study examined the effects of PTSD on motor response inhibition, a key cognitive control function. A Go/NoGo task was administered to veterans with a diagnosis of PTSD based on semi-structured clinical interview using DSM-IV criteria (n = 40) and age-matched control veterans (n = 33). Participants also completed questionnaires to assess self-reported levels of PTSD and depressive symptoms. Performance measures from the patients (error rates and reaction times) were compared to those from controls. PTSD patients showed a significant deficit in response inhibition, committing more errors on NoGo trials than controls. Higher levels of PTSD and depressive symptoms were associated with higher error rates. Of the three symptom clusters, re-experiencing was the strongest predictor of performance. Because the co-morbidity of mild traumatic brain injury (mTBI) and PTSD was high in this population, secondary analyses compared veterans with PTSD+mTBI (n = 30) to veterans with PTSD only (n = 10). Although preliminary, results indicated the two patient groups did not differ on any measure (p > .88). Since cognitive impairments could hinder the effectiveness of standard PTSD therapies, incorporating treatments that strengthen executive functions might be considered in the future. (JINS, 2012, 18, 1–10)

Corpus callosum malformation and dysfunction are increasingly recognized causes of cognitive and behavioral disability. Individuals with agenesis of the corpus callosum (AgCC) offer unique insights regarding the cognitive skills that depend specifically upon callosal connectivity. We examined the impact of AgCC on cognitive inhibition, flexibility, and processing speed using the Color-Word Interference Test (CWIT) and Trail Making Test (TMT) from the Delis-Kaplan Executive Function System. We compared 36 individuals with AgCC and IQs within the normal range to 56 matched controls. The AgCC cohort was impaired on timed measures of inhibition and flexibility; however, group differences on CWIT Inhibition, CWIT Inhibition/Switching and TMT Number-Letter Switching appear to be largely explained by slow performance in basic operations such as color naming and letter sequencing. On CWIT Inhibition/Switching, the AgCC group was found to commit significantly more errors which suggests that slow performance is not secondary to a cautious strategy. Therefore, while individuals with agenesis of the corpus callosum show real deficits on tasks of executive function, this impairment appears to be primarily a consequence of slow cognitive processing. Additional studies are needed to investigate the impact of AgCC on other aspects of higher order cortical function. (JINS, 2012, 18, 521–529)

The CAMCOG, ADAS-cog, and MMSE, designed to grade global cognitive ability in dementia have inadequate precision and accuracy in distinguishing mild dementia from normal ageing. Adding neuropsychological tests to their scale might improve precision and accuracy in mild dementia. We, therefore, pooled neuropsychological test-batteries from two memory clinics (ns = 135 and 186) with CAMCOG data from a population study and 2 memory clinics (n = 829) and ADAS-cog data from 3 randomized controlled trials (n = 713) to estimate a common dimension of global cognitive ability using Rasch analysis. Item difficulties and individuals’ global cognitive ability levels were estimated. Difficulties of 57 items (of 64) could be validly estimated. Neuropsychological tests were more difficult than the CAMCOG, ADAS-cog, and MMSE items. Most neuropsychological tests had difficulties in the ability range of normal ageing to mild dementia. Higher than average ability levels were more precisely measured when neuropsychological tests were added to the MMSE than when these were measured with the MMSE alone. Diagnostic accuracy in mild dementia was consistently better after adding neuropsychological tests to the MMSE. We conclude that extending dementia specific instruments with neuropsychological tests improves measurement precision and accuracy of cognitive impairment in mild dementia. (JINS, 2012, 18, 314–322)

Two major challenges facing researchers interested in cognitive change are that measures of change are often not very reliable, and they may reflect effects of prior test experience in addition to the factors of primary interest. One approach to dealing with these problems is to obtain multiple measures of change on parallel versions of the same tests in a measurement burst design. A total of 783 adults performed three parallel versions of cognitive tests on two occasions separated by an average of 2.6 years. Performance increased substantially across the three sessions within each occasion, and for all but vocabulary ability these within-occasion improvements were considerably larger than the between-occasion changes. Reliabilities of the changes in composite scores were low, but averages of the three changes had larger, albeit still quite modest, reliabilities. In some cognitive abilities individual differences were evident in the relation of prior test experience and the magnitude of longitudinal change. Although multiple assessments are more time consuming than traditional measurement procedures, the resulting estimates of change are more robust than those from conventional methods, and also allow the influence of practice on change to be systematically investigated. (JINS, 2012, 18, 1–8)

It is “normal” for old age to be associated with gradual decline in memory and brain mass. However, there are anecdotal reports of individuals who seem immune to age-related memory impairment, but these individuals have not been studied systematically. This study sought to establish that such cognitive SuperAgers exist and to determine if they were also resistant to age-related loss of cortical brain volume. SuperAgers were defined as individuals over age 80 with episodic memory performance at least as good as normative values for 50- to 65-year-olds. Cortical morphometry of the SuperAgers was compared to two cognitively normal cohorts: age-matched elderly and 50- to 65-year-olds. The SuperAgers’ cerebral cortex was significantly thicker than their healthy age-matched peers and displayed no atrophy compared to the 50- to 65-year-old healthy group. Unexpectedly, a region of left anterior cingulate cortex was significantly thicker in the SuperAgers than in both elderly and middle-aged controls. Our findings identify cognitive and neuroanatomical features of a cohort that appears to resist average age-related changes of memory capacity and cortical volume. A better understanding of the underlying factors promoting this potential trajectory of unusually successful aging may provide insight for preventing age-related cognitive impairments or the more severe changes associated with Alzheimer's disease. (JINS, 2012, 18, 1–5)

The present study sought to evaluate the Wechsler Test of Adult Reading (WTAR) Full-Scale IQ (FSIQ) estimate as an index of premorbid ability in a sample 574 of healthy college athletes participating in a sports concussion management program. We compared baseline neuropsychological test performance with the WTAR FSIQ estimate obtained at baseline. Results revealed that the discrepancy between actual neuropsychological test scores and the WTAR FSIQ estimate was greatest for those with estimated FSIQs greater than 107. The clinical implication of this finding was evaluated in the 51 participants who went on to sustain a concussion. For individuals with higher IQ estimates, the WTAR estimate obtained post-concussion suggested greater post-concussion decline than that indicated by comparison with actual baseline neuropsychological performance. (JINS, 2012, 18, 139–143)

Although frontal patients show impaired decision-making on the Iowa Gambling Task (IGT), there has been no follow-up study to date to determine whether there is recovery of function over time. We examined neurological participants’ performance on repeated administrations of the IGT over the course of 6 years. We found that, while non-neurological participants showed considerable improvement due to practice effects on the IGT, patients with ventromedial prefrontal cortex (VMPFC) damage persisted in showing impaired performance on each retest. These results validate the clinical observations that VMPFC dysfunction does not appear to be subject to autonomous recovery over time in real-life. (JINS, 2012, 18, 1–4)

The objective of this study is to assess attention in recently diagnosed relapsing-remitting multiple sclerosis patients. Twenty-seven patients with early multiple sclerosis and low clinical disability scores (EDSS<2) and 27 sex-, age-, and education-matched healthy controls underwent attention assessment using the Attentional Network Test, a computerized task designed to measure efficiency independently in 3 attentional networks (Alerting, Orienting and Executive Control). MS patients had significantly less efficiency in the Alerting network (p = .006). In contrast, in the Orienting and Executive Control networks, they did not differ from controls. A significant interaction between Alerting and Executive Control was also found in the MS patients (p = .007). Early relapsing-remitting multiple sclerosis particularly affects the Alerting domain of attention, whereas the Orienting and Executive Control domains are not affected. (JINS, 2012, 18, 1–7)