Recent studies have reported abnormal implicit learning of sequential patterns in patients with schizophrenia. Because these studies were based on visuospatial cues, the question remained whether patients were impaired simply due to the demands of spatial processing. This study examined implicit sequence learning in 24 patients with schizophrenia and 24 healthy controls using a non-spatial variation of the serial reaction time test (SRT) in which pattern stimuli alternated with random stimuli on every other trial. Both groups showed learning by responding faster and more accurately to pattern trials than to random trials. Patients, however, showed a smaller magnitude of sequence learning. Both groups were unable to demonstrate explicit knowledge of the nature of the pattern, confirming that learning occurred without awareness. Clinical variables were not correlated with the patients' learning deficits. Patients with schizophrenia have a decreased ability to develop sensitivity to regularly occurring sequences of events within their environment. This type of deficit may affect an array of cognitive and motor functions that rely on the perception of event regularity. (JINS, 2005, 11, 659–667.)

The title of each session is linked to its abstract in the Table of Contents included at the start of the PDF file. Readers wishing to view a particular abstract can select the appropriate session title in the Table of Contents.

This study examined the impact of irrelevant dimensional variation on rule-based category learning in patients with Parkinson's disease (PD), older controls (OC), and younger controls (YC). Participants were presented with 4-dimensional, binary-valued stimuli and were asked to categorize each into 1 of 2 categories. Category membership was based on the value of a single dimension. Four experimental conditions were administered in which there were zero, 1, 2, or 3 randomly varying irrelevant dimensions. Results indicated that patients with PD were impacted to a greater extent than both the OC and YC participants when the number of randomly varying irrelevant dimensions increased. These results suggest that the degree of working memory and selective attention requirements of a categorization task will impact whether PD patients are impaired in rule-based category learning, and help to clarify recent discrepancies in the literature. (JINS, 2005, 11, 503–513.)

The objective of this study is to examine the prognosis of acute cognitive disorders post-stroke, and to evaluate which clinical factors predict domain-specific cognitive recovery. We followed the course of cognitive functioning in 111 stroke patients and 77 healthy controls by administering two neuropsychological examinations with a 6 to 10 month interval (mean interval, 7.5 ± 1.3 months). The baseline examination was administered within three weeks post-stroke (mean interval, 7.9 ± 4.2 days). To examine determinants of domain-specific cognitive recovery, we recorded vascular risk factors, clinical variables, and lesion characteristics. Recovery in visual perception/construction (83%) and visual memory (78%) was the most common. An acute cognitive disorder predicted a long-term disorder in the same domain (all p < .05), except for visual perception/construction. Factors associated with poor cognitive recovery were age (all p < .01), preexistent verbal ability (all p < .005), lesion locations involving the temporal (all p < .05), frontal (p < .05) and occipital lobe (all p < .05), lesion volume (p ≤ .001), and diabetes mellitus (p < .01). An early neuropsychological examination provides valuable information on long-term cognitive performance. The prognosis of higher-level visual disorders is the most favorable. Cognitive recovery is associated with age, preexistent ability, lesion volume, lesion location, and diabetes mellitus. (JINS, 2005, 11, 795–806.)

the title of each session is linked to its abstract in the table of contents included at the start of the pdf file. readers wishing to view a particular abstract can select the appropriate session title in the table of contents.

There continues to be debate about the long-term neuropsychological impact of mild traumatic brain injury (MTBI). A meta-analysis of the relevant literature was conducted to determine the impact of MTBI across nine cognitive domains. The analysis was based on 39 studies involving 1463 cases of MTBI and 1191 control cases. The overall effect of MTBI on neuropsychological functioning was moderate (d = .54). However, findings were moderated by cognitive domain, time since injury, patient characteristics, and sampling methods. Acute effects (less than 3 months postinjury) of MTBI were greatest for delayed memory and fluency (d = 1.03 and .89, respectively). In unselected or prospective samples, the overall analysis revealed no residual neuropsychological impairment by 3 months postinjury (d = .04). In contrast, clinic-based samples and samples including participants in litigation were associated with greater cognitive sequelae of MTBI (d = .74 and .78, respectively at 3 months or greater). Indeed, litigation was associated with stable or worsening of cognitive functioning over time. The implications and limitations of these findings are discussed. (JINS, 2005, 11, 215–227.)

There is increasing interest in the potential neuropsychological impact of sports-related concussion. A meta-analysis of the relevant literature was conducted to determine the impact of sports-related concussion across six cognitive domains. The analysis was based on 21 studies involving 790 cases of concussion and 2014 control cases. The overall effect of concussion (d = 0.49) was comparable to the effect found in the non-sports-related mild traumatic brain injury population (d = 0.54; Belanger et al., 2005). Using sports-concussed participants with a history of prior head injury appears to inflate the effect sizes associated with the current sports-related concussion. Acute effects (within 24 hr of injury) of concussion were greatest for delayed memory, memory acquisition, and global cognitive functioning (d = 1.00, 1.03, and 1.42, respectively). However, no residual neuropsychological impairments were found when testing was completed beyond 7 days postinjury. These findings were moderated by cognitive domain and comparison group (control group versus preconcussion self-control). Specifically, delayed memory in studies utilizing a control group remained problematic at 7 days. The implications and limitations of these findings are discussed. (JINS, 2005, 11, 345–357.)

This marks the official beginning of my tenure as Editor-in-Chief of JINS though the transition has been ongoing for more than a year. The change you will notice most is the cover, but I have also instituted a new section, Neurobehavioral Grand Rounds, which is a way to emphasize the importance of case studies by including an introduction by an expert in the field who will put the case in a broader context. Other sections will remain the same except I have changed the name of Research Letters to Rapid Communications, and I want to encourage you to submit such papers that are short, and are put on a fast track for review. Electronic submission and review is still in its infancy, but I am optimistic that it will speed the review process. Speedy publication is in all of our interests, but rapid, high quality reviews are the cornerstone of that speed. Therefore, when JINS asks you to review a manuscript, please agree to do it. We will be relying heavily on your help in order to improve the review lag.

From a public health standpoint, identifying factors that contribute to risky sexual practices among substance-dependent individuals is critical, particularly in the context of HIV infection. This study examines the respective contributions of executive neurocognitive functions, sensation seeking, and HIV serostatus in predicting risky sexual practices among poly-substance users (with a history of dependence primarily for cocaine or cocaine/heroin). HIV+ (n = 109) and HIV− (n = 154) substance-dependent individuals were assessed using three neurocognitive tasks of executive functions: Stroop reaction time, delayed non-matching to sample, and the Iowa Gambling Task. Sensation seeking was assessed using the Sensation Seeking Scale–V. Greater sensation seeking was associated with more risky sexual practices among HIV+ participants, particularly among those who performed best on the Iowa Gambling Task. Our findings indicate that continued risk behavior among HIV+ drug users may be driven by sensation seeking (a personality trait common among drug users); however, the impact of executive functions is less clear. (JINS, 2005, 11, 121–131.)

Confrontation naming ability entails the operation of distinct cognitive operations and the integrity of a distributed neural network. Previous research has indicated a critical role for the left temporal lobe region in naming ability, but there is less agreement about the relative role of distinct temporal lobe regions. In the current paper, we used quantitative MR volumetrics to investigate the relative contribution of the hippocampus and extrahippocampal temporal lobe (segmented gray and white matter) volumes to confrontation naming performance in 53 patients with temporal lobe epilepsy. Findings showed (1) a stronger relationship for left temporal lobe volume than right temporal lobe volume in predicting naming performance; (2) both left temporal lobe white matter volume and left hippocampus volume contributed a significant amount of unique variance to spontaneous naming performance; and (3) left temporal lobe white matter volume but not left hippocampus volume predicted recognition naming performance. (JINS, 2005, 11, 358–366.)

Previous research has provided evidence of metamemory impairments in patients with frontal lobe damage on verbal episodic memory tasks. In the present study, we employed metamemory paradigms to investigate whether patients with frontal lesions show monitoring deficits on semantic memory tasks involving facial stimuli. Patients with frontal lobe damage and healthy control subjects made memory decisions to famous faces in a retrospective confidence judgment task and in a prospective feeling-of-knowing (FOK) task. Results indicated that frontal patients performed worse than controls on the retrospective confidence task, but there were no differences between the groups on the FOK task. These findings suggest that metamemory deficits in frontal patients are not confined to specific stimulus domains (words vs. faces) or memory systems (episodic vs. semantic). In addition, the dissociation between retrospective confidence judgments and FOK accuracy documented in this study and also in a recent report by Schnyer et al. suggesting that metamemory should not be considered a unitary function with a single neuroanatomic substrate. (JINS, 2005, 11, 668–676.)

Mild traumatic brain injury (MTBI) is common, yet few studies have examined neuropsychological outcomes more than 1 year postinjury. Studies of nonreferred individuals with MTBI or studies with appropriate control groups are lacking, but necessary to draw conclusions regarding natural recovery from MTBI. We examined the long-term neuropsychological outcomes of a self-reported MTBI an average of 8 years postinjury in a nonreferred community-dwelling sample of male veterans. This was a cross-sectional cohort study derived from the Vietnam Experience Study. Three groups matched on premorbid cognitive ability were examined, those who (1) had not been injured in a MVA nor had a head injury (Normal Control; n = 3214), (2) had been injured in a motor vehicle accident (MVA) but did not have a head injury (MVA Control; n = 539), and (3) had a head injury with altered consciousness (MTBI; n = 254). A MANOVA found no group differences on a standard neuropsychological test battery of 15 measures. Across 15 measures, the average neuropsychological effect size of MTBI compared with either control group was −.03. Subtle aspects of attention and working memory also were examined by comparing groups on Paced Auditory Serial Addition Test (PASAT) continuation rate and California Verbal Learning Test (CVLT) proactive interference (PI). Compared with normal controls, the MTBI group evidenced attention problems in their lower rate of continuation to completion on the PASAT (odds ratio = 1.32, CI = 1.0–1.73) and in excessive PI (odds ratio = 1.66, CI = 1.11–2.47). Unique to the MTBI group, PASAT continuation problems were associated with left-sided visual imperceptions and excessive PI was associated with impaired tandem gait. These results show that MTBI can have adverse long-term neuropsychological outcomes on subtle aspects of complex attention and working memory. (JINS, 2005, 11, 228–236.)

The aim of the study was to investigate whether age affects visual memory retention across extended time intervals. In addition, we wanted to study how memory capabilities across different time intervals are related to the volume of different neuroanatomical structures (right hippocampus, right cortex, right white matter). One test of recognition (CVMT) and one test of recall (Rey-Osterrieth Complex Figure Test) were administered, giving measures of immediate recognition/recall, 20–30 min recognition/recall, and recognition/recall at a mean of 75 days. Volumetric measures of right hemisphere hippocampus, cortex, and white matter were obtained through an automated labelling procedure of MRI recordings. Results did not demonstrate a steeper rate of forgetting for older participants when the retention intervals were increased, indicating that older people have spared ability to retain information in the long-term store. Differences in neuroanatomical volumes could explain up to 36% of the variance in memory performance, but were not significantly related to rates of forgetting. Cortical volume and hippocampal volume were in some cases independent as predictors of memory function. Generally, cortical volume was a better predictor of recognition memory than hippocampal volume, while the 2 structures did not differ in their predictive power of recall abilities. While neuroanatomical volumetric differences can explain some of the differences in memory functioning between younger and older persons, the hippocampus does not seem to be unique in this respect. (JINS, 2005, 11, 2–15.)

Patients with unilateral, right frontal lobe damage (N = 13) and matched controls (N = 20) performed a task of lexical ambiguity resolution in order to explore the contribution of right frontal regions to lexical-semantic priming. Word triplets consisting of balanced homographs were presented to participants in four conditions: concordant, discordant, neutral, and unrelated. Controls demonstrated facilitation for concordant meanings of homographs, as evidenced by their faster reaction times in the concordant relative to the unrelated (baseline) condition, as well as a lack of facilitation for the discordant meaning relative to the neutral and concordant conditions. Results in patients with right frontal lobe damage differed depending on the site of the lesion. Patients with lesions restricted to the right medial frontal lobe only showed facilitation in the neutral condition, while those with lesions encroaching upon the right dorsolateral region demonstrated facilitation of both discordant and concordant meanings relative to the baseline condition. These results support a role for the right frontal lobe in semantic priming and suggest possible specialization within the right prefrontal cortex for the processing of lexical-semantic information. (JINS, 2005, 11, 132–143.)

As many as 50% of multiple sclerosis (MS) patients experience clinical or subclinical depression. A voluminous literature has documented affective memory biases (AMB) among depressed individuals. Despite this, little is known regarding how depressive symptoms may affect MS patients' ability to recall positive and negative material. The present study employed an affective list-learning task that increased cognitive load and inhibited the use of higher order encoding strategies. The purpose of the study was twofold: to determine whether MS patients exhibit AMB and to examine whether subvocal repetition and other higher order encoding strategies are essential to the formation of AMB among people experiencing depression. Results indicated a strong relationship between depression and AMB in MS. The results are discussed in relation to existing biological research that indicates limbic and/or other subcortical systems may play a role in the formation of AMB. (JINS, 2005, 11, 514–521.)

Although substantial information exists about factors related to who returns to work and time taken to return to work after traumatic brain injury (TBI), less is known about the stability of the work experience after the injury. One hundred sixty-five workers with complicated mild to severe traumatic brain injury were followed for 3 to 5 years postinjury. Work stability definitions included amount of time worked (amount of time worked divided by time observed postinjury) and maintenance of uninterrupted employment once a person returned to work. Amount of time worked was significantly and systematically related to brain injury severity, neuropsychological functioning at 1-month postinjury, and preinjury characteristics such as prior work stability and earnings. However, once persons returned to work, the ability to maintain uninterrupted employment was largely related to premorbid characteristics such as being older, higher income before the injury, or a preinjury job with benefits. It was also related to higher neuropsychological functioning at 1-month postinjury (reflecting the combined effects of premorbid functioning and traumatic brain injury severity), but not related to neurologic indices of severity. (JINS, 2005, 11, 807–816.)

Past research has shown that lesions in the left cerebral hemisphere often result in aphasia, while lesions in the right hemisphere frequently impair the production of emotional prosody and facial expression. At least 3 processing deficits might account for these affective symptoms: (1) failure to understand the conditions that evoke emotional response; (2) inability to experience emotions; (3) disruption in the capacity to encode non-verbal signals. To better understand these disorders and their underlying mechanisms, we investigated spontaneous affective communication in right hemisphere damaged (RHD) stroke patients with aprosody and left hemisphere damaged (LHD) stroke patients with aphasia. Nine aprosodic RHD patients and 14 aphasic LHD patients participated in a videotaped interview within a larger treatment protocol. Two naïve raters viewed segments of videotape and rated facial expressivity. Verbal affect production was tabulated using specialized software. Results indicated that RHD patients smiled and laughed significantly less than LHD patients. In contrast, RHD patients produced a greater percentage of emotion words relative to total words than did LHD patients. These findings suggest that impairments in emotional prosodic production and facial expressivity associated with RHD are not induced by affective–conceptual deficits or an inability to experience emotions. Rather, they likely represent channel-specific nonverbal encoding abnormalities. (JINS, 2005, 11, 677–685.)

Thirty unilateral anterior temporal lobectomy (ATL) subjects (15 right and 15 left) and 15 controls were presented a multitrial learning task in which unfamiliar faces were paired with biographical information (occupation, city location, and a person's name). Face recognition hits were similar between groups, but the right ATL group committed more false-positive errors to face foils. Both left and right ATL groups were impaired relative to controls in acquiring biographical information, but the deficit was more pronounced for the left ATL group. Recall levels also varied for the different types of biographical information; occupation was most commonly recalled followed by city name and person name. In addition, city and person name recall was more likely when occupation was also recalled. Overall, recall of biographical information was positively correlated with clinical measures of anterograde episodic memory. Findings are discussed in terms of the role of the temporal lobe and associative learning ability in the successful acquisition of new face semantic (biographical) representations. (JINS, 2005, 11, 237–248.)