This study examined everyday action impairment in participants with Parkinson's disease dementia (PDD) by comparison with participants with Parkinson's disease-no dementia (PD) or Alzheimer's disease (AD) and in reference to a neuropsychological model. Participants with PDD (n = 20), PD (n = 20), or AD (n = 20) were administered performance-based measures of everyday functioning that allowed for the quantification of overall performance and error types. Also, caregiver ratings of functional independence were obtained. On performance-based tests, the PDD group exhibited greater functional impairment than the PD group but comparable overall impairment relative to the AD group. Error patterns did not differ between PDD and PD participants but the PDD group demonstrated a higher proportion of commission errors and lower proportion of omission errors relative to the AD group. Hierarchical regression analyses showed omission errors were significantly predicted by neuropsychological measures of episodic memory, whereas commission errors were predicted by both measures of general dementia severity (MMSE) and executive control. Everyday action impairment in PDD differs quantitatively from PD but qualitatively from AD and may be characterized by a relatively high proportion of commission errors—an error type associated with executive control deficits. (JINS, 2012, 18, 1–12)

Olfactory hallucinations (OHs) are present in a significant minority of people with schizophrenia, yet these symptoms are under-researched and poorly understood. This study aimed to identify the neuropsychological impairments that associate with OHs in schizophrenia. Patients with schizophrenia or schizoaffective disorder were classified into an OH group and a group with auditory-verbal hallucinations (AVHs) and no lifetime history of OHs. Patients were age- and gender-matched to a healthy control group. All participants were assessed using: a test of odor identification; decision-making and socio-emotional tests of orbitofrontal cortex (OFC) and amygdala function; and a battery of standardized executive tests. Patients, as a whole, performed more poorly than controls on the tests of odor identification, emotion processing and executive function, consistent with previous research. Only two tests of OFC functioning: the Object Alternation Task, taken from Oscar-Berman and Zola-Morgan's (1980a, 1980b) Comparative Neuropsychological Tasks, and a test of “faux pas” understanding discriminated between the OH and AVH patients. Findings provide the first preliminary support for OH-specific neuropsychological impairments associated with OFC dysfunction in schizophrenia. (JINS, 2012, 18, 1–10)

The present study investigates selective attention and verbal free recall in amyotrophic lateral sclerosis (ALS) and examines the contribution of selective attention, encoding, consolidation, and retrieval memory processes to patients’ verbal free recall. We examined 22 non-demented patients with sporadic ALS and 22 demographically related controls using Stroop Neuropsychological Screening Test (SNST; selective attention) and Rey Auditory Verbal Learning Test (RAVLT; immediate & delayed verbal free recall). The item-specific deficit approach (ISDA) was applied to RAVLT to evaluate encoding, consolidation, and retrieval difficulties. ALS patients performed worse than controls on SNST (p < .001) and RAVLT immediate and delayed recall (p < .001) and showed deficient encoding (p = .001) and consolidation (p = .002) but not retrieval (p = .405). Hierarchical regression analysis revealed that SNST and ISDA indices accounted for: (a) 91.1% of the variance in RAVLT immediate recall, with encoding (p = .016), consolidation (p < .001), and retrieval (p = .032) significantly contributing to the overall model and the SNST alone accounting for 41.6%; and (b) 85.2% of the variance in RAVLT delayed recall, with consolidation (p < .001) and retrieval (p = .008) significantly contributing to the overall model and the SNST alone accounting for 39.8%. Thus, selective attention, encoding, and consolidation, and to a lesser extent of retrieval, influenced both immediate and delayed verbal free recall. Concluding, selective attention and the memory processes of encoding, consolidation, and retrieval should be considered while interpreting patients’ impaired free recall. (JINS, 2012, 18, 1–10)

Prior investigations have shown that individuals with attention deficit hyperactivity disorder (ADHD) have impaired neuropsychological functions. This study had two aims, first to investigate weakened cognitive functions in adult ADHD (aADHD), and second, to investigate difference between persisters (those having persistently ongoing ADHD diagnosis in adulthood), and remitters (those having ADHD diagnosis only in childhood and not in adulthood), in terms of cognitive deficits. We evaluated performance on a comprehensive neuropsychological battery in three groups including 34 persisters, 35 remitters, and 35 healthy control group (absence of childhood and adulthood ADHD diagnosis). Our findings showed that adults with ADHD have inefficient attention, interference control and set-shifting functions, which may be revealed on neuropsychological tests that require greater cognitive demand. Given the finding that interference control deficit exists across the lifespan in people with ADHD, we suggest that interference control-associated functional weakness may be a core deficit for ADHD. (JINS, 2012, 18, 1–8)

Cannabis use is associated with risky sexual behavior (RSB) and sex-related negative health consequences. This investigation examined the role of inhibitory control and episodic memory in predicting RSB and sex-related negative consequences among current cannabis users. Findings indicated that the relationships among cannabis, neurocognition, and sexual-risk varied according to the dimension of neurocognition and the parameter of RSB in question. Specifically, more risk-taking was associated with more RSB. Furthermore, amount of recent cannabis use was associated with more RSB and sex-related negative consequences, but only among those with worse performances on a measure of decision-making and of risk-taking. Contrary to hypotheses, worse episodic memory also significantly predicted higher overall sexual-risk and decreased safe-sex practices. Results indicate that worse neurocognitive performance in the areas of risk-taking, decision-making, and episodic memory may influence the degree to which cannabis users engage in RSB and experience negative health consequences as a result. (JINS, 2012, 18, 1–7)

On tests of design fluency, an examinee draws as many different designs as possible in a specified time limit while avoiding repetition. The neuroanatomical substrates and diagnostic group differences of design fluency repetition errors and total correct scores were examined in 110 individuals diagnosed with dementia, 53 with mild cognitive impairment (MCI), and 37 neurologically healthy controls. The errors correlated significantly with volumes in the right and left orbitofrontal cortex (OFC), the right and left superior frontal gyrus, the right inferior frontal gyrus, and the right striatum, but did not correlate with volumes in any parietal or temporal lobe regions. Regression analyses indicated that the lateral OFC may be particularly crucial for preventing these errors, even after excluding patients with behavioral variant frontotemporal dementia (bvFTD) from the analysis. Total correct correlated more diffusely with volumes in the right and left frontal and parietal cortex, the right temporal cortex, and the right striatum and thalamus. Patients diagnosed with bvFTD made significantly more repetition errors than patients diagnosed with MCI, Alzheimer's disease, semantic dementia, progressive supranuclear palsy, or corticobasal syndrome. In contrast, total correct design scores did not differentiate the dementia patients. These results highlight the frontal-anatomic specificity of design fluency repetitions. In addition, the results indicate that the propensity to make these errors supports the diagnosis of bvFTD. (JINS, 2012, 18, 1–11)

This study explored whether remote blast-related MTBI and/or current Axis I psychopathology contribute to neuropsychological outcomes among OEF/OIF veterans with varied combat histories. OEF/OIF veterans underwent structured interviews to evaluate history of blast-related MTBI and psychopathology and were assigned to MTBI (n = 18), Axis I (n = 24), Co-morbid MTBI/Axis I (n = 34), or post-deployment control (n = 28) groups. A main effect for Axis I diagnosis on overall neuropsychological performance was identified (F(3,100) = 4.81; p = .004), with large effect sizes noted for the Axis I only (d = .98) and Co-morbid MTBI/Axis I (d = .95) groups relative to the control group. The latter groups demonstrated primary limitations on measures of learning/memory and processing speed. The MTBI only group demonstrated performances that were not significantly different from the remaining three groups. These findings suggest that a remote history of blast-related MTBI does not contribute to objective cognitive impairment in the late stage of injury. Impairments, when present, are subtle and most likely attributable to PTSD and other psychological conditions. Implications for clinical neuropsychologists and future research are discussed. (JINS, 2012, 18, 1–11)

Existing evidence suggests that psychosocial stress is associated with cognitive impairment in older adults. Perceived discrimination is a persistent stressor in African Americans that has been associated with several adverse mental and physical health outcomes. To our knowledge, the association of discrimination with cognition in older African Americans has not been examined. In a cohort of 407 older African Americans without dementia (mean age = 72.9; SD = 6.4), we found that a higher level of perceived discrimination was related to poorer cognitive test performance, particularly episodic memory (estimate = −0.03; SE = .013; p < .05) and perceptual speed tests (estimate = −0.04; SE = .015; p < .05). The associations were unchanged after adjusting for demographics and vascular risk factors, but were attenuated after adjustment for depressive symptoms (Episodic memory estimate = −0.02; SE = 0.01; Perceptual speed estimate = −0.03; SE = 0.02; both p's = .06). The association between discrimination and several cognitive domains was modified by level of neuroticism. The results suggest that perceived discrimination may be associated with poorer cognitive function, but does not appear to be independent of depressive symptoms. (JINS, 2012, 18, 1–10)

Participants diagnosed with mild cognitive impairment (MCI), dementia and controls completed measures that required decoding emotions from point-light displays of bodily motion, and static images of facial affect. Both of these measures tap social cognitive processes that are considered critical for social competency. Consistent with prior literature, both clinical groups were impaired on the static measure of facial affect recognition. The dementia (but not the MCI) group additionally showed difficulties interpreting biological motion cues. However, this did not reflect a specific deficit in decoding emotions, but instead a more generalized difficulty in processing visual motion (both to action and to emotion). These results align with earlier studies showing that visual motion processing is disrupted in dementia, but additionally show for the first time that this extends to the recognition of socially relevant biological motion. The absence of any MCI related impairment on the point-light biological emotion measure (coupled with deficits on the measure of facial affect recognition) also point to a potential disconnect between the processes implicated in the perception of emotion cues from static versus dynamic stimuli. For clinical (but not control) participants, performance on all recognition measures was inversely correlated with level of semantic memory impairment. (JINS, 2012, 18, 1–8)

The association of cerebral white matter lesions (WMLs) with cognitive status is not well understood in middle-aged individuals. Our aim was to determine the specific contribution of periventricular hyperintensities (PVHs) and deep white matter hyperintensities (DWMHs) to cognitive function in a community sample of asymptomatic participants aged 50 to 65 years. One hundred stroke- and dementia-free adults completed a comprehensive neuropsychological battery and brain MRI protocol. Participants were classified according to PVH and DWMH scores (Fazekas scale). We dichotomized our sample into low grade WMLs (participants without or with mild lesions) and high grade WMLs (participants with moderate or severe lesions). Analyses were performed separately in PVH and DWMH groups. High grade DWMHs were associated with significantly lower scores in executive functioning (−0.45 standard deviations [SD]), attention (−0.42 SD), verbal fluency (−0.68 SD), visual memory (−0.52 SD), visuospatial skills (−0.79 SD), and psychomotor speed (−0.46 SD). Further analyses revealed that high grade DWMHs were also associated with a three- to fourfold increased risk of impaired scores (i.e.,<1.5 SD) in executive functioning, verbal fluency, visuospatial skills, and psychomotor speed. Our findings suggest that only DWMHs, not PVHs, are related to diminished cognitive function in middle-aged individuals. (JINS, 2012, 18, 1–12)

The earliest cognitive deficits observed in amnestic mild cognitive impairment (aMCI) appear to center on memory tasks that require relational memory (RM), the ability to link or integrate unrelated pieces of information. RM impairments in aMCI likely reflect neural changes in the medial temporal lobe (MTL) and posterior parietal cortex (PPC). We tested the hypothesis that individuals with aMCI, as compared to cognitively normal (CN) controls, would recruit neural regions outside of the MTL and PPC to support relational memory. To this end, we directly compared the neural underpinnings of successful relational retrieval in aMCI and CN groups, using event-related functional magnetic resonance imaging (fMRI), holding constant the stimuli and encoding task. The fMRI data showed that the CN, compared to the aMCI, group activated left precuneus, left angular gyrus, right posterior cingulate, and right parahippocampal cortex during relational retrieval, while the aMCI group, relative to the CN group, activated superior temporal gyrus and supramarginal gyrus for this comparison. Such findings indicate an early shift in the functional neural architecture of relational retrieval in aMCI, and may prove useful in future studies aimed at capitalizing on functionally intact neural regions as targets for treatment and slowing of the disease course. (JINS, 2012, 18, 1–12)

While distal sensory polyneuropathy (DSP) is the most common neurological condition associated with HIV, causing nerve damage in upper and lower extremities, its impact on neuropsychological test performance is unclear. In this study, we analyzed baseline data for 278 HIV-infected participants with comprehensive neurological and neurocognitive evaluations to examine the contribution of DSP and anatomic distribution of neuropathic signs (upper extremity or lower extremity) on standardized domain scores. We found that participants with DSP performed significantly worse in multiple domains containing timed psychomotor tests (i.e., motor, information processing speed and executive functioning). With regard to executive functioning, differences were limited to a test with a motor component (Trail Making Test, Part B). The group with clinically detectable neuropathic signs in the upper extremities and the group with signs limited to the lower extremities both performed worse in the motor domain than the group without DSP. Participants with DSP demonstrated a unique pattern of impairment limited to neuropsychological domains with timed psychomotor tests. These results suggest that caution should be used in interpretation of neuropsychological tests in patients with DSP, as some abnormalities may be exacerbated by peripheral nervous system pathology. (JINS, 2012, 19, 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)

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)

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)