Showing papers in "Journal of The International Neuropsychological Society in 2008"

Neuropsychology and clinical neuroscience of persistent post-concussive syndrome.

Abstract: On the mild end of the acquired brain injury spectrum, the terms concussion and mild traumatic brain injury (mTBI) have been used interchangeably, where persistent post-concussive syndrome (PPCS) has been a label given when symptoms persist for more than three months post-concussion. Whereas a brief history of concussion research is overviewed, the focus of this review is on the current status of PPCS as a clinical entity from the perspective of recent advances in the biomechanical modeling of concussion in human and animal studies, particularly directed at a better understanding of the neuropathology associated with concussion. These studies implicate common regions of injury, including the upper brainstem, base of the frontal lobe, hypothalamic-pituitary axis, medial temporal lobe, fornix, and corpus callosum. Limitations of current neuropsychological techniques for the clinical assessment of memory and executive function are explored and recommendations for improved research designs offered, that may enhance the study of long-term neuropsychological sequelae of concussion. (JINS, 2008, 14, 1–22.)

Memory impairment, executive dysfunction, and intellectual decline in preclinical Alzheimer's disease.

Abstract: In the Baltimore Longitudinal Study of Aging (BLSA), we examined the temporal unfolding of declining performance on tests of episodic memory (Free Recall on the Free and Cued Selective Reminding Test), executive function (Category Fluency, Letter Fluency, and Trails), and Verbal Intelligence (Nelson, 1982; American Version of the Nelson Adult Reading Test [AMNART]) before the diagnosis of dementia in 92 subjects with incident Alzheimer's disease (AD) followed for up to 15 years before diagnosis. To examine the preclinical onset of cognitive decline, we aligned subjects at the time of initial AD diagnosis and examined the cognitive course preceding diagnosis. We found that declines in performance on tests of episodic memory accelerated 7 years before diagnosis. Declining performance on tests of executive function accelerated 2-3 years before diagnosis, and verbal intelligence declined in close proximity to diagnosis. This cognitive profile is compatible with pathologic data suggesting that structures which mediate memory are affected earlier than frontal structures during the preclinical onset of AD. It also supports the view that VIQ as estimated by the AMNART does not decline during the preclinical onset of AD.

Functional outcome 10 years after traumatic brain injury: its relationship with demographic, injury severity, and cognitive and emotional status.

Abstract: Previous investigations of long-term outcome following traumatic brain injury (TBI) have yielded mixed results regarding the predictive power of injury severity and demographic factors. Furthermore, there has been limited investigation of the association between long-term outcome and current cognitive functioning and psychiatric state. The aim of this study was to investigate the association of injury severity, demographic factors, and concurrent cognitive and psychiatric functioning with functional outcome 10 years following mild to severe TBI. Outcome was rated using the Extended Glasgow Outcome Scale (GOSE) for 60 participants, who also completed neuropsychological measures of attention, speed of processing, memory and executive function and the Hospital Anxiety and Depression Scale (HADS). Outcome on the GOSE ranged from upper good recovery (32%) to lower severe disability (2%). Participants showing poorer outcome on the GOSE had significantly longer posttraumatic amnesia duration; less education; performed more poorly on cognitive measures of information processing speed, attention, memory, and executive function; and showed higher levels of anxiety on the HADS. (JINS, 2008, 14, 233–242.)

Depression in multiple sclerosis: review and theoretical proposal

Abstract: Because of its high prevalence and implications for quality of life and possibly even disease progression, depression has been intensively studied in multiple sclerosis (MS) over the past 25 years. Despite the publication of numerous excellent empirical research papers on this topic during that time, the publication of theoretical work that attempts to explain depression in a comprehensive way is scarce. In this study, we present a theoretical model that attempts to integrate existing work on depression in MS and provide testable hypotheses for future work. The model suggests that risk for depression begins with the onset of MS. MS results in disease-related changes such as increased lesion burden/brain atrophy and immunological anomalies that are associated with depression in MS, but explain only a relatively limited proportion of the variance. Common sequelae of MS including fatigue, physical disability, cognitive dysfunction, and pain, have all been shown to have an inconsistent or relatively weak relationship to depression in the literature. In the model, we propose that four variables--social support, coping, conceptions of the self and illness, and stress--may moderate the relationship between the above common MS sequelae with depression and help to explain inconsistencies in the literature.

Frequency and bases of abnormal performance by healthy adults on neuropsychological testing.

Abstract: The frequency and determinants of abnormal test performance by normal individuals are critically important to clinical inference. Here we compare two approaches to predicting rates of abnormal test performance among healthy individuals with the rates actually shown by 327 neurologically normal adults aged 18–92 years. We counted how many participants produced abnormal scores, defined by three different cutoffs with test batteries of varied length, and the number of abnormal scores they produced. Observed rates generally were closer to predictions based on a series of Monte Carlo simulations than on the binomial model. They increased with the number of tests administered, decreased as more stringent cutoffs were used to identify abnormality, varied with the degree of correlation among test scores, and depended on individual differences in age, education, race, sex, and estimated premorbid IQ. Adjusting scores for demographic variables and premorbid IQ did not reduce rates of abnormal performance. However, it eliminated the contribution of these variables to rates of abnormal test performance. These findings raise fundamental questions about the nature and interpretation of abnormal test performance by normal, healthy adults. (JINS, 2008, 14, 436–445.)

Effects of prenatal alcohol exposure on hippocampal volume, verbal learning, and verbal and spatial recall in late childhood

Abstract: Children with prenatal alcohol exposure (PAE) show deficits in verbal learning and spatial memory, as well as abnormal hippocampal development. The relationship between their memory and neuroanatomic impairments, however, has not been directly explored. Given that the hippocampus is integral for the synthesis and retrieval of learned information and is particularly vulnerable to the teratogenic effects of alcohol, we assessed whether reduced learning and recall abilities in children with fetal alcohol spectrum disorders (FASDs) are associated with abnormal hippocampal volumes. Nineteen children with FASDs and 18 typically developing controls aged 9 to 15 years were assessed for verbal learning and verbal and spatial recall and underwent structural magnetic resonance imaging. Images were analyzed for total intracranial volume and for right and left hippocampal volumes. Results revealed smaller left hippocampi and poorer verbal learning and verbal and spatial recall performance in children with FASDs than controls, as well as positive correlations between selective memory indices and hippocampal volumes only in the FASD group. Additionally, hippocampal volumes increased significantly with age in controls only, suggesting that PAE may be associated with long-term abnormalities in hippocampal development that may contribute to impaired verbal learning and verbal and spatial recall. (JINS, 2008, 14, 1022–1033.)

Emotion perception deficits following traumatic brain injury: a review of the evidence and rationale for intervention.

Abstract: While the cognitive disturbances that frequently follow severe traumatic brain injury (TBI) are relatively well understood, the ways in which these affect the psychosocial functioning of people with TBI are yet to be determined and have thus received little attention in treatment research. Growing evidence indicates that a significant proportion of individuals with TBI demonstrate an inability to recognize affective information from the face, voice, bodily movement, and posture. Because accurate interpretation of emotion in others is critical for the successful negotiation of social interactions, effective treatments are necessary. Until recently, however, there have been no rehabilitation efforts in this area. The present review examines the literature on emotion perception deficits in TBI and presents a theoretical rationale for targeted intervention. Several lines of research relevant to the remediation of emotion perception in people with TBI are considered. These include work on emotion perception remediation with other cognitively impaired populations, current neuropsychological models of emotion perception and underlying neural systems, and recent conceptualizations of remediation processes. The article concludes with a discussion of the importance of carrying out efforts to improve emotion perception within a contextualized framework in which the day-to-day relevance of training is clear to all recipients.

Affective response to eye contact and face recognition ability in children with ASD.

Abstract: This study tested the hypothesis that affective arousal in response to eye contact is negatively associated with face identification skills in children with autism spectrum disorder (ASD). Participants were 20 children and adolescents with ASD and 20 age- and IQ-matched typically developing (TD) children. Skin conductance response (SCR), a psychophysiological measure of autonomic arousal, was collected while participants viewed faces with gaze directed toward them and faces with gaze averted away from them. Participants also completed an independent match-to-sample face recognition test. Children with ASD exhibited significantly larger SCRs than TD children to faces with direct and averted gaze. There were no differences between SCRs to direct gaze and averted gaze in either group. Children with ASD exhibited a marginally significant decrease in face recognition accuracy relative to TD children, particularly when face recognition depended on the eye region of the face. Face recognition accuracy among children with ASD was negatively correlated with the amplitude of SCRs to direct gaze but not to averted gaze. There was no association between face recognition accuracy and SCRs to gaze in the TD group. These findings suggest that autonomic reactivity to eye contact may interfere with face identity processing in some children with ASD. ( JINS , 2008, 14 , 947–955.)

Social behavior following traumatic brain injury and its association with emotion recognition, understanding of intentions, and cognitive flexibility.

Abstract: Although the adverse consequences of changes in social behavior following traumatic brain injury (TBI) are well documented, relatively little is known about possible underlying neuropsychological deficits. Following a model originally developed for social behavior deficits in schizophrenia, we investigated whether impairments in emotion recognition, understanding of other people’s intentions (“theory of mind”), and cognitive flexibility soon after first TBI or 1 year later were associated with self and proxy ratings of behavior following TBI. Each of the three functions was assessed with two separate tests, and ratings of behavior were collected on three questionnaires. Patients with TBI (n 5 33) were impaired in emotion recognition, “theory of mind,” and cognitive flexibility compared with matched orthopedic controls (n 5 34). Proxy ratings showed increases in behavioral problems 1 year following injury in the TBI group but not in the control group. However, test performance was not associated with questionnaire data. Severity of the impairments in emotion recognition, understanding intention, and flexibility were unrelated to the severity of behavioral problems following TBI. These findings failed to confirm the used model for social behavior deficits and may cast doubt on the alleged link between deficits in emotion recognition or theory of mind and social functioning. (JINS, 2008, 14, 318–326.)

Executive functioning in preschool children born very preterm: Relationship with early white matter pathology.

Abstract: Despite evidence for executive dysfunction in school-aged preterm children, less is known about the early development of these difficulties or their underlying neuropathology. This study used prospective longitudinal data from a regional cohort of 88 very preterm and 98 full-term comparison children to examine the executive functioning (EF) of preschool children born very preterm. The relationship between the severity of neonatal cerebral white matter (WM) abnormalities on magnetic resonance imaging (MRI) at term equivalent and children's EF at ages two and four years (corrected age) was examined. At age four, very preterm children with WM abnormalities performed less well than full-term children on the Detour Reaching Box, a measure of behavioral inhibition and cognitive flexibility, even after controlling for child IQ, SES, and medical background. Examination of patterns of EF performance between the ages of 2 and 4 years showed that the performance of all groups improved with age. However, very preterm children with mild and moderate-severe WM abnormalities were characterized by higher rates of consistent performance impairments. These findings support the presence of early and persistent executive difficulties in preschool children born very preterm, and highlight the importance of white matter pathology in the development of executive impairments. (JINS, 2008, 14, 90–101.)

Potential for misclassification of mild cognitive impairment: a study of memory scores on the Wechsler Memory Scale-III in healthy older adults.

Abstract: The psychometric criterion of mild cognitive impairment (MCI) generally involves having an unusually low score on memory testing (i.e., −1.5 SDs). However, healthy older adults can obtain low scores, particularly when multiple memory measures are administered. In turn, there is a substantial risk of psychometrically misclassifying MCI in healthy older adults. This study examined the base rates of low memory scores in older adults (55–87 years; n = 550) from the Wechsler Memory Scale–Third Edition (WMS-III; Wechsler, 1997b) standardization sample. The WMS-III consists of four co-normed episodic memory tests (i.e., Logical Memory, Faces, Verbal Paired Associates, and Family Pictures) that yield eight age- and demographically-adjusted standard scores (Auditory Recognition and Working Memory tests not included). When the eight age-adjusted scores were examined simultaneously, 26% of older adults had one or more scores at or below the 5th percentile (i.e., −1.5 SDs). On the eight demographically- adjusted scores, 39% had at least one score at or below the 5th percentile. There was an inverse relationship between intellectual abilities and prevalence of low memory scores, particularly with the age-adjusted WMS-III scores. Understanding the base rates of low scores can reduce the overinterpretation of low memory scores and minimize false-positive misclassification.Drs. Brooks, Iverson, and Feldman have no known, perceived, or actual conflict of interest with this research. Dr. Holdnack is the Senior Research Director with The Psychological Corporation. (JINS, 2008, 14, 463–478.)

Trajectory of mild cognitive impairment onset.

Abstract: The objective was to identify the trajectories of onset of memory and other cognitive loss in persons destined to develop mild cognitive impairment (MCI) or dementia. Healthy, community dwelling, cognitively intact elders (n = 156, mean age at entry = 83 years) were examined annually for an average of greater than 7 years. Those who developed at least two consecutive Clinical Dementia Ratings >or= 0.5 were classified as having MCI. Longitudinal mixed effects models with a change point were used to model the aging process in those with and without an MCI diagnosis during follow-up and to model the rate of change relative to the age of onset of MCI. MCI had a preclinical stage of accelerated cognitive loss that was observed 3 to 4 years before the diagnosis of MCI on tests of verbal memory, animal fluency, and visuospatial constructions. Evidence from memory performance before the change point suggests that a slow decline in memory precedes the period of accelerated decline in the development of MCI. Aging transitions leading to MCI and dementia are characterized by unique linear and nonlinear cognitive changes in several domains that precede the diagnosis of MCI and dementia by at least several years.

Executive function, mentalizing and humor in major depression.

Abstract: Major depression is associated with cognitive deficits including memory, executive functions, and affect perception, which have been linked to dysfunction of fronto-subcortical networks. However, little is known about social cognition on more complex socially relevant tasks, such as humor processing. In this investigation a computerized humor-processing task was administered to 27 patients with a diagnosis of major depression (Dep) and 27 healthy controls (HC). Theory of mind (mentalizing) and executive functions were also assessed. Both groups were similar in IQ, age, and gender. Depressed patients performed below the control group with respect to both affective and cognitive aspects of humor processing, and these were related to mentalizing and executive performance. Our findings suggest social cognition deficits in major depression. Ability to process humor and appreciate mentalistic perspectives may in turn influence social interactions and should be given consideration in therapeutic approaches to depression.

Differences in executive functioning in children with heavy prenatal alcohol exposure or attention-deficit/hyperactivity disorder.

Abstract: Children with either fetal alcohol spectrum disorder (FASD) or attention-deficit/hyperactivity disorder (ADHD) display deficits in attention and executive function (EF) and differential diagnosis of these two clinical groups may be difficult, especially when information about prenatal alcohol exposure is unavailable The current study compared EF performance of three groups: children with heavy prenatal alcohol exposure (ALC); nonexposed children with attention-deficit/hyperactivity disorder (ADHD); and typically developing controls (CON) Both clinical groups met diagnostic criteria for ADHD The EF tasks used were the Wisconsin Card Sorting Test (WCST), the Controlled Oral Word Association Test (COWAT), and the Trail Making Test (TMT) Results indicated different patterns of deficit; both clinical groups displayed deficits on the WCST and a relative weakness on letter versus category fluency Only the ALC group displayed overall deficits on letter fluency and a relative weakness on TMT-B versus TMT-A In addition, WCST performance was significantly lower than expected based on IQ in the ADHD group and significantly higher than expected in the ALC group These results, which indicate that, although EF deficits occurred in both clinical groups, the degree and pattern of deficit differed between the ALC and ADHD groups, may improve differential diagnosis

Frontal contributions to face processing differences in autism: evidence from fMRI of inverted face processing.

Abstract: Functional neuroimaging studies of face processing deficits in autism have typically focused on visual processing regions, such as the fusiform face area (FFA), which have shown reduced activity in autism spectrum disorders (ASD), though inconsistently. We recently reported reduced activity in the inferior frontal region in ASD, implicating impaired mirror-neuron systems during face processing. In the present study, we used fMRI during a face processing task in which subjects had to match faces presented in the upright versus inverted position. Typically developing (TD) children showed a classic behavioral inversion effect, increased reaction time for inverted faces, while this effect was significantly reduced in ASD subjects. The fMRI data showed similar responses in the fusiform face area for ASD and TD children, with both groups demonstrating increased activation for inverted faces. However, the groups did differ in several brain regions implicated in social cognition, particularly prefrontal cortex and amygdala. These data suggest that the behavioral differences in processing upright versus inverted faces for TD children are related not to visual information processing but to the social significance of the stimuli. Our results are consistent with other recent studies implicating frontal and limbic dysfunction during face processing in autism.

fMRI activation during a language task in adolescents with ASD.

Abstract: Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by language and communication impairments, social impairments, and repetitive behaviors or restricted interests. Previous studies of semantic functions have found differences in semantic processing and differences in the activation of the language network in adults with ASD compared to controls. The goal of this study is to examine semantic functions in adolescents with ASD compared to typically developing adolescents. We utilized fMRI with a reading version of a response-naming task to investigate activation in 12 right-handed adolescent boys with ASD and 12 typically developing boys. Both groups performed the task at ceiling levels. Boys with ASD had significantly stronger activation than controls in Broca's area, which was less left lateralized in ASD individuals. Controls had a significant correlation between frontal and temporal language area activation in the left hemisphere, whereas ASD adolescents did not. Direct group comparisons revealed additional regions activated in the ASD group relative to the control group. These results suggest differences in semantic organization, approaches to the semantic task, or efficiency in semantic processing in ASD adolescents relative to typically developing adolescents.

Neuronal fiber pathway abnormalities in autism: an initial MRI diffusion tensor tracking study of hippocampo-fusiform and amygdalo-fusiform pathways.

Abstract: MRI diffusion-tensor tracking (DTT) was performed in 17 high-functioning adolescents/adults with autism and 17 pairwise-matched controls. White matter pathways involved in face processing were examined due to the relevance of face perception to the social symptoms of autism, and due to known behavioral and functional imaging findings in autism. The hippocampo-fusiform (HF) and amygdalo-fusiform (AF) pathways had normal size and shape but abnormal microstructure in the autism group. The right HF had reduced across-fiber diffusivity (D-min) compared with controls, opposite to the whole-brain effect of increased D-min. In contrast, left HF, right AF, and left AF had increased D-min and increased along-fiber diffusivity (D-max), more consistent with the whole-brain effect. There was a general loss of lateralization compared with controls. The right HF D-min was markedly low in the autism subgroup with lower Benton face recognition scores, compared with the lower-Benton control subgroup, and compared with the higher-Benton autism subgroup. Similar behavioral relationships were found for performance IQ. Such results suggest an early functionally-significant pathological process in right HF consistent with small-diameter axons (with correspondingly slower neural transmission) and/or higher packing density. In left AF and HF, changes were interpreted as secondary, possibly reflecting axonal loss and/or decreased myelination.

Traumatic brain injury in young children: postacute effects on cognitive and school readiness skills.

Abstract: Previous studies have documented weaknesses in cognitive ability and early academic readiness in young children with traumatic brain injury (TBI). However, few of these studies have rigorously controlled for demographic characteristics, examined the effects of TBI severity on a wide range of skills, or explored moderating influences of environmental factors on outcomes. To meet these objectives, each of three groups of children with TBI (20 with severe, 64 with moderate, and 15 with mild) were compared with a group of 117 children with orthopedic injuries (OI group). The children were hospitalized for their injuries between 3 and 6 years of age and were assessed an average of 1 1/2 months post injury. Analysis revealed generalized weaknesses in cognitive and school readiness skills in the severe TBI group and less pervasive effects of moderate TBI. Indices of TBI severity predicted outcomes within the TBI sample and environmental factors moderated the effects of TBI on some measures. The findings document adverse effects of TBI in early childhood on postacute cognitive and school readiness skills and indicate that these effects are related to both injury severity and the family environment.

Functional implications of neuropsychological normality and symptom remission in older outpatients diagnosed with schizophrenia: A cross-sectional study

Abstract: Cognitive impairments in schizophrenia are well documented and correlated with functional disability. Although some patients demonstrate normal neuropsychological (NP) functioning, little is known about their functional disability. We examined the cross-sectional functional implications of NP normality and symptomatic remission in older outpatients with schizophrenia or schizoaffective disorder, who were administered a NP battery and performance-based measures of functional and social competence, with their real-world functioning rated by case managers. NP status was classified by the General Deficit Score (GDS) and remission status was based on the Positive and Negative Syndrome Scale (PANSS), yielding four subsamples of patients: NP normal-remitted (n=21), NP normal-symptomatic (n=22), NP impaired-remitted (n=90), and NP impaired-symptomatic (n=97). NP normal patients demonstrated better functional and social competence and better ratings of real-world functioning, after controlling for premorbid abilities. However, compared to normative date, NP normal patients manifested disability in several real-world domains, including residential status. These results suggest that NP status is a better predictor of functional outcome then symptom status or the interaction of the two factors. The disability seen in NP normal cases indicates that factors other than cognitive impairments may determine aspects of everyday outcomes in schizophrenia.

Cognitive complaint in mild cognitive impairment and Alzheimer's disease.

Abstract: Whereas the presence of a subjective memory complaint is a central criteria for mild cognitive impairment (MCI), little work has been done to empirically measure its nature and severity. The Self-Evaluation Questionnaire (QAM) assessed memory complaints relative to 10 domains of concrete activities of daily life in 68 persons with MCI, 26 persons with Alzheimer's disease (AD), and 81 healthy older adults. In addition, a neuropsychological battery was administered to assess whether subjective complaints were linked to actual cognitive performance. The findings indicate that individuals with MCI report more memory complaints than controls for a range of specific materials/circumstances. MCI and AD individuals did not differ in their level of memory complaints. Correlational analyses indicated that a higher level of memory complaints relative to conversations and to movies and books were associated with a higher level of objective cognitive deficits in persons with MCI but not in AD. Furthermore, complaints increased in parallel with global cognitive deficits in MCI. These results suggest that persons with MCI report more memory complaints than healthy older controls, but only in specific domains and circumstances, and that anosognosia is more characteristic of the demented than of the MCI phase of Alzheimer's disease.

Executive function and metacognitive self-awareness after severe traumatic brain injury.

Abstract: The objective of this study is to identify the clinical, neuropsychological, neuropsychiatric, and functional variables that correlate with metacognitive self-awareness (SA) in severe traumatic brain injury (TBI) outpatients and to assess the influence of the same variables on the sensory-motor, cognitive, and behavioral-affective indicators of SA. This cross-sectional observational study evaluated 37 outpatients from May 2006 to June 2007 in a neurorehabilitation hospital on the basis of the following inclusion criteria: (1) age 8); (3) posttraumatic amnesia (PTA) resolution; (4) capacity to undergo formal psychometric evaluation despite cognitive and sensory-motor deficits; (5) absence of aphasia; (6) availability of informed consent. A neuropsychological battery was used to evaluate attention, memory, and executive functions. SA was assessed by the awareness questionnaire (AQ), administered to both patients and relatives. Decreased metacognitive self-awareness is significantly correlated with increased problems in some components of executive system, even when the AQ subscales were considered separately. The significant correlation found between some components of executive system and metacognitive self-awareness confirmed the importance of addressing this issue to treat SA contextually in the rehabilitation of executive functions.

Neuroimaging of working memory dysfunction and the dilemma with brain reorganization hypotheses.

Abstract: There is a growing literature examining working memory deficits using functional imaging and there has been great convergence in the findings, to date, but interpretations have varied. Investigators consistently observed recruitment of neural resources in clinical samples, with some examiners attributing these findings to neural inefficiency and others attributing differences to neural compensation and/or brain reorganization. It is the goal of this paper to address the current interpretation of altered brain activation in clinical imaging studies of working memory dysfunction with specific emphasis on findings in prefrontal cortex (PFC). Throughout this review, the methods used to examine brain reorganization associated with working memory dysfunction are critiqued with the goal of understanding how study design has influenced data interpretation. It is proposed that much of what has been considered "aberrant" neural activity is not indicative of neural compensation, as it has been typically defined, and does not represent brain reorganization. Instead, recruitment of neural resources in PFC can be explained by a natural, and largely overlooked, role of cognitive control in accommodating neural dysfunction secondary to brain injury and disease. This paper provides predictions based on this proposition and a critique of the current methods available for testing these predictions.

Explicit memory training leads to improved memory for face-name pairs in patients with mild cognitive impairment: results of a pilot investigation.

Abstract: Relatively few studies have examined the use of cognitive rehabilitation in patients with mild cognitive impairment (MCI), largely due to the assumption that training will not improve functioning in patients with progressive conditions. Face-name association, an ecologically valid task, is both dependent on the explicit memory system and difficult for MCI patients. During three hour-long sessions, eight patients diagnosed with MCI were trained in the use of explicit memory strategies with 45 face-name pairs. For each pair, they were taught to visually identify a facial feature, link a phonological cue to that feature, and recall the associated name. There was significant improvement in recognition accuracy, along with faster reaction times, for trained face-name pairs. Improved accuracy persisted when tested one month after training. Significant, but less, improvement was also found on untrained stimuli, raising the possibility of generalization of training strategies. Preliminary results suggest strategy-based cognitive rehabilitation may be beneficial in patients with MCI, though these results must be replicated with a control group to rule out practice effects. (JINS, 2008, 14, 883–889.)

Inability to empathize following traumatic brain injury.

Abstract: This study examines: (a) the impact of traumatic brain injury (TBI) on emotional empathy, (b) the relationship between emotional empathy and neuropsychological ability, and (c) the influence of low emotional empathy on measures of affect. Eighty-nine patients completed the Balanced Emotional Empathy Scale (BEES), a number of neuropsychological tests, some of which were ecologically valid tests of executive ability, plus two measures of affect, the Beck Anxiety Inventory (BAI) and Beck Depression Inventory (BDI). The TBI cohort showed a high frequency (60.7%) of low emotional empathy scores compared to the control group (31%). There was no relationship between injury severity and the ability to empathize, or between emotional empathy and neuropsychological performance. There was no evidence to suggest that low scores on affective measures influenced emotional empathy scores. A high proportion of TBI patients lack the ability to empathize, but the deficit does not appear related to any specific cognitive impairment and cannot be predicted by measures of affect.

Differential neuropsychological test sensitivity to left temporal lobe epilepsy

Abstract: We examined the sensitivity of the Rey Auditory Verbal Learning Test (AVLT), California Verbal Learning Test (CVLT), Boston Naming Test (BNT), and Multilingual Aphasia Examination Visual Naming subtest (MAE VN) to lateralized temporal lobe epilepsy (TLE) in patients who subsequently underwent anterior temporal lobectomy. For the AVLT (n = 189), left TLE patients performed more poorly than their right TLE counterparts [left TLE = 42.9 (10.6), right TLE = 47.7 (9.9); p < .002 (Cohen's d = .47)]. Although statistically significant, the CVLT group difference (n = 212) was of a smaller magnitude [left LTE = 40.7 (11.1), right TLE = 43.8 (9.9); (p < .03, Cohen's d = .29)] than the AVLT. Group differences were also present for both measures of confrontation naming ability [BNT: left LTE = 43.1 (8.9), right TLE = 48.1 (8.9); p < .001 (Cohen's d = .56); MAE VN: left TLE = 42.2, right TLE = 45.6, p = .02 (Cohen's d = .36)]. When these data were modeled in independent logistic regression analyses, the AVLT and BNT both significantly predicted side of seizure focus, although the positive likelihood ratios were modest. In the subset of 108 patients receiving both BNT and AVLT, the AVLT was the only significant predictor of seizure laterality, suggesting individual patient variability regarding whether naming or memory testing may be more sensitive to lateralized TLE.

The moderating role of negative affect on objective verbal memory performance and subjective memory complaints in healthy older adults.

Abstract: Subjective memory complaints (SMCs) are part of the diagnostic criteria for Mild Cognitive Impairment (MCI), yet little is known about their etiology. In some previous studies, no direct relation has been found between SMCs and objective memory performance, yet significant correlations have been identified between SMCs and psychological factors such as depression and anxiety. In the current study, we examined whether negative affect moderated the relation between objective memory functioning and SMCs in a sample of healthy, non-demented participants aged 65 and older. As predicted, several negative affect measures moderated the relationship between objective cognitive functioning and SMCs. In the absence of objective memory impairment as indexed by the Rey Auditory Verbal Learning Test (RAVLT) and the Dementia Rating Scale-2nd Edition (DRS-2), higher levels of negative affect were associated with increased levels of SMCs. Moreover, a lower order negative affect factor, anxiety sensitivity, significantly moderated the relation between objective memory functioning and SMCs, after controlling for higher order measures of general negative affectivity. Findings suggest that negative affect, particularly anxiety sensitivity, distorts the subjective appraisal of one's own memory, such that people high on negative affect factors report more episodes of forgetting, even in the absence of objective cognitive impairments. (JINS, 2008, 14, 327–336.)

Relative Sensitivity of Magnetic Resonance Spectroscopy and Quantitative Magnetic Resonance Imaging to Cognitive Function Among Nondemented Individuals Infected with HIV

Abstract: In the present study, we examined the relationships among cognitive function, magnetic resonance spectroscopy (MRS) brain metabolite indices measured in the basal ganglia, and quantitative magnetic resonance imaging (MRI) of the caudate nucleus and the putamen in the earliest stages of HIV-related cognitive involvement. Participants included 22 HIV-positive individuals and 20 HIV-negative individuals. HIV-positive individuals performed significantly more poorly than the HIV-negative individuals on several cognitive measures. In addition, the choline/creatine ratio was significantly higher and the N-acetyl aspartate/choline ratio was significantly lower among HIV patients. The caudate and putamen sizes were smaller among HIV-positive patients compared with controls; however, the differences did not reach statistical significance. Correlation analyses revealed associations between cognitive function and select MRS indices. In addition, caudate size was significantly correlated with performances on higher-order thinking tests whereas putamen size was significantly correlated with performances on motor tests. The results suggest that MRS differences are more pronounced than area size differences between seropositive and seronegative individuals in mild stages of HIV-related cognitive impairment. However, basal ganglia size remains an important contributor to cognitive status in this population. Longitudinal studies are needed to determine the evolution of these imaging correlates of HIV-cognitive impairment in HIV.

Subjective memory complaints and concurrent memory performance in older patients of primary care providers.

Abstract: Subjective memory complaints (SMCs) are known to be inconsistently related to current memory impairment in older adults but this association has not been well investigated in primary care provider (PCP) settings. To characterize the complexity of the relationship between SMCs and objective memory in older outpatients of PCPs, we collected neuropsychological, subjective memory, depression and medical chart data from outpatients aged 65 and older, without documented dementia diagnoses, in eleven PCP offices in and around the Pittsburgh metropolitan area. Results indicated that self-estimates of current memory ability were most strongly associated with objective memory performance; in contrast, perception of worsening memory over the past year showed no association; and specific memory-related activities were only weakly associated. Women were more likely than men to show inconsistency between SMCs and objective memory performance. Only two of the 11 most significantly memory-impaired participants endorsed SMCs and only four had PCP chart documentation of memory problems. Eliciting SMCs in non-demented older adults can be of clinical value in a PCP setting, but significant limitations of patient self-report in more memory-impaired patients underscore the need to develop brief, objective indicators of memory impairment for PCP office use when there is suspicion of decline.

Neuropsychological and behavioral functioning in children with and without obstructive sleep apnea referred for tonsillectomy.

Abstract: Adenotonsillectomy (AT) is among the most common pediatric surgical procedures and is performed as often for obstructive sleep apnea (OSA) as for recurrent tonsillitis. This study compared behavioral, cognitive, and sleep measures in 27 healthy control children recruited from a university hospital-based pediatric general surgery clinic with 40 children who had OSA (AT/OSA+) and 27 children who did not have OSA (AT/OSA−) scheduled for AT. Parental ratings of behavior, sleep problems, and snoring, along with specific cognitive measures (i.e., short term attention, visuospatial problem solving, memory, arithmetic) reflected greater difficulties for AT children compared with controls. Differences between the AT/OSA− and control groups were larger and more consistent across test measures than were those between the AT/OSA+ and control groups. The fact that worse outcomes were not clearly demonstrated for the AT/OSA+ group compared with the other groups was not expected based on existing literature. This counterintuitive finding may reflect a combination of factors, including age, daytime sleepiness, features of sleep-disordered breathing too subtle to show on standard polysomnography, and academic or environmental factors not collected in this study. These results underscore the importance of applying more sophisticated methodologies to better understand the salient pathophysiology of childhood sleep-disordered breathing.

Cognitive models of medical decision-making capacity in patients with mild cognitive impairment.

Abstract: This study investigated cognitive predictors of medical decision-making capacity (MDC) in patients with amnestic mild cognitive impairment (MCI). A total of 56 healthy controls, 60 patients with MCI, and 31 patients with mild Alzheimer's disease (AD) were administered the Capacity to Consent to Treatment Instrument (CCTI) and a neuropsychological test battery. The CCTI assesses MDC across four established treatment consent standards--S1 (expressing choice), S3 (appreciation), S4 (reasoning), and S5 (understanding)--and one experimental standard [S2] (reasonable choice). Scores on neuropsychological measures were correlated with scores on each CCTI standard. Significant bivariate correlates were subsequently entered into stepwise regression analyses to identity group-specific multivariable predictors of MDC across CCTI standards. Different multivariable cognitive models emerged across groups and consent standards. For the MCI group, measures of short-term verbal memory were key predictors of MDC for each of the three clinically relevant standards (S3, S4, and S5). Secondary predictors were measures of executive function. In contrast, in the mild AD group, measures tapping executive function and processing speed were primary predictors of S3, S4, and S5. MDC in patients with MCI is supported primarily by short-term verbal memory. The findings demonstrate the impact of amnestic deficits on MDC in patients with MCI.