Executive Function

A series of stages that are the inverse of Kohlberg's stages are summarized, along with vignettes from "Dirty Heinz Stories". The antisocial stages are based upon responses of incarcerated adolescents to the Executive Judgment Inventory, recorded interviews, and the autobiographies of career criminals,

Decline in episodic memory is one of the most prominent cognitive deficits seen in late adulthood. It is therefore surprising that few studies have examined how the related capacity for episodic foresight might also be affected in this age group. Preliminary evidence suggests that older adults show deficits in generating phenomenological characteristics of future events, but the critical question of whether such deficits extend to generating and executing appropriate future intentions remains to be addressed. Here, we present 2 studies. In Study 1, we report the results of our pilot testing, which was used to develop and validate stimuli for the first measure of this construct that is appropriate for use in adult populations. In Study 2, we administer this measure to 40 older and 40 younger adults. The results indicate that, relative to their younger counterparts, older adults are less likely to spontaneously acquire items that would later allow a problem to be solved, and are also ...

Background: Postnatal dexamethasone (DXM) treatment is associated with adverse motor outcome. It is largely unknown as to what extent functional outcome at school age is affected. Aims: Our first aim was to determine motor, cognitive, and behavioural outcome at school age of preterm-born children treated with high-dose DXM for pulmonary problems. Our second aim was to identify DXM-related risk factors for adverse outcome. Study design: In this cohort study, we included 53 very preterm-born children treated with DXM (starting dose 0.5 mg/kg/d) after the first week of life. At the median age of 9 years, we performed a detailed neuropsychological assessment. Results: Compared to the norm population, DXM-treated children scored worse on the Movement-ABC (abnormal fine motor, ball skills and balance: 59%, 47% and 30%, respectively). They more often had total (36%), verbal (32%) and performance IQs (55%) below 85 (P b .001, P = .002, P b .001, respectively). On each of the remaining measures, DXM-treated children scored worse than the norm population, except for verbal long-term memory and verbal recognition memory. DXM-related risk factors were associated with poorer performance. Conclusions: At school age, multiple domains of functional outcome were affected in DXM-treated children. Risk factors related to the use of DXM should be considered as serious potentiaters of adverse outcome in children treated with high-dose DXM. Please cite this article as: Hitzert MM, et al, Functional outcome at school age of preterm-born children treated with high-dose dexamethasone, Early Hum Dev (2014), http://dx.

Executive function is recognized as a critical component of children's cognitive and social development. In two studies, a measure of executive function that had been used in research with chimpanzees was adapted for preschoolers. On this task, called Less Is More, children must point to a smaller reward (two candies) to receive a larger reward (five candies). In Study 1 (TV = 101), per- formance was significantly related to age (3 vs. 4), verbal ability, and established measures of executive function. In Study 2 (N = 128), symbolic representations substituted for real candies in this task. Three-year-olds9 performance improved significantly as a function of symbolic distancing. This research has implications for the role of symbol sys- tems in the development of executive control over thought and action.

Chronic pain conditions are complicated and challenging to live with. Capacity to adjust to such conditions may depend on the ability to self-regulate, that is, the ability to alter thoughts, feelings, and behaviors. Self-regulation appears to rely on executive cognitive functions, and the current review, therefore, sought to draw attention to the impact of self-regulatory capacity and executive functions on chronic pain. Chronic pain conditions present with complex interactions of cognitive, emotional, behavioral, and physiological components for which self-regulatory ability is crucial. The ability to self-regulate varies, and self-regulatory strength appears to be a limited resource that can be fatigued. The many challenges of chronic pain conditions could, therefore, tax self-regulatory strength, leading to self-regulatory deficits. The current review proposes a relationship among pain, self-regulatory capacity, self-regulatory demands, executive functions, and self-regulatory fatigue, suggesting that executive functions and self-regulatory deficits are indeed part of the etiology and maintenance of chronic pain conditions.

This selective review article examines treatment and intervention strategies for executive function (EF) deficits within the school environment. We begin by providing a broad definition of EF. We then examine the scope of EF deficits within the school setting and identify profiles of special populations of students who present with such deficits. A focus is placed on the developmental trajectory that both EF and the frontal lobes follow and how this drives the selection and effectiveness of treatments and interventions at particular ''critical periods'' throughout a child's academic career. Direct and indirect school-based diagnostic assessment methods to identify EF deficits in students will be briefly reviewed. Against that background, various treatment methods and intervention strategies to remediate both cognitive and affective EF deficits within the confines of the school setting will be presented. Individual and group intervention strategies will be presented as will their current acceptance within the scientific community and applicability to the educational arena. The importance of incorporating school-based neuropsychological assessment methods that aid in the differential diagnosis of academic and behavioral difficulties directly related to EF will also be discussed, as the accurate identification of these impairments is necessary to facilitate data-based decision making when selecting the most appropriate interventions following a developmental model in educational settings. Topics addressing EF treatment modalities and research-based interventions for clinical and school-based practitioners to consider within educational settings will also be presented as suggestions for future research with pediatric populations.

Executive functioning deficits characterize the neuropsychological profiles of the childhood neurodevelopmental disorders of attention deficit hyperactivity disorder (ADHD) and autistic spectrum disorder (ASD). This study sought to determine whether similar impairments exist in adults with ADHD (N = 53) and ASD (N = 45) in comparison with a healthy control group (N = 31), whether the two disorders can be distinguished on the basis of their executive functioning features, and whether these impairments are related to symptom severity. Both clinical groups were found to exhibit executive functioning deficits. The ADHD group had difficulty withholding a response, with relative preservation of initiation and planning abilities. In contrast, the ASD group exhibited significant impairments in initiation, planning and strategy formation. The specific executive functioning deficits were related to severity of response inhibition impairments in ADHD and stereotyped, repetitive behaviours in ASD. These findings suggest the autism

Virtual reality (VR) head-mounted displays (HMD) appear to be effective research tools,
which may address the problem of ecological validity in neuropsychological testing.
However, their widespread implementation is hindered by VR induced symptoms
and effects (VRISE) and the lack of skills in VR software development. This study
offers guidelines for the development of VR software in cognitive neuroscience and
neuropsychology, by describing and discussing the stages of the development of Virtual
Reality Everyday Assessment Lab (VR-EAL), the first neuropsychological battery in
immersive VR. Techniques for evaluating cognitive functions within a realistic storyline
are discussed. The utility of various assets in Unity, software development kits, and other
software are described so that cognitive scientists can overcome challenges pertinent
to VRISE and the quality of the VR software. In addition, this pilot study attempts to
evaluate VR-EAL in accordance with the necessary criteria for VR software for research
purposes. The VR neuroscience questionnaire (VRNQ; Kourtesis et al., 2019b) was
implemented to appraise the quality of the three versions of VR-EAL in terms of user
experience, game mechanics, in-game assistance, and VRISE. Twenty-five participants
aged between 20 and 45 years with 12–16 years of full-time education evaluated various
versions of VR-EAL. The final version of VR-EAL achieved high scores in every sub-score
of the VRNQ and exceeded its parsimonious cut-offs. It also appeared to have better
in-game assistance and game mechanics, while its improved graphics substantially increased the quality of the user experience and almost eradicated VRISE. The results
substantially support the feasibility of the development of effective VR research and
clinical software without the presence of VRISE during a 60-min VR session.

INTRODUCTION Despite the serious behavioral consequences faced by individuals with sexual compulsivity, related neuropsychological studies are sparse. AIM To compare decision making and cognitive flexibility at baseline and after exposure to an erotic video in sexually compulsive participants and non-sexually compulsive controls. METHODS The sample consisted of 30 sexually compulsive men and 30 controls. Cognitive flexibility was investigated through the Wisconsin Card Sorting Test and decision making was examined through the Iowa Gambling Task. MAIN OUTCOME MEASURES Wisconsin Card Sorting Test categories, correct responses, and perseverative errors and Iowa Gambling Task general trends and blocks. RESULTS Sexually compulsive subjects and controls performed similarly at baseline. After watching an erotic video, controls performed better in block 1 of the Iowa Gambling Task (P = .01) and had more correct responses on the Wisconsin Card Sorting Test (P = .01). CONCLUSIONS The controls...

Aging is often associated with modifications of gait. Recent studies have revealed a strong relationship between gait and executive functions in healthy and pathological aging. We hypothesized that modification of gait due to aging may be related to changes in frontal lobe function.

Background: School-age preterm children are at risk for cognitive difficulties including Executive Dysfunction and low average IQ. Aim: The aim of this study was to determine the performance of very preterm, school-age children on three components of Executive Function (EF), two components of Executive Attention and a measure of IQ. Study design: Cross-sectional, independent samples comparison. Methods: A UK sample of 40 very preterm (b 32 weeks gestational age, Mean 28.43, SD 2.41) children and 41 term born control children aged between 6 and 12 years (mean ages 8 years 5 months in both groups) was assessed on IQ, EF (inhibition, working memory and set shifting) and attention (sustained and selective). Between group comparisons were made using multivariate analysis of variance and covariance. Results: Multivariate analyses indicated that preterm children scored significantly lower than their term born peers across Executive Function and executive attention tasks. As expected, the preterm group achieved IQ scores at the low end of the average range. Univariate analyses indicated some difficulties with shifting and inhibition components of EF, although covariate analysis revealed that only shifting was independent of IQ. Conclusions: Preterm children showed mild executive function and executive attention difficulties in the context of average IQ scores. The findings highlight the benefit of using multivariate assessments of executive skills rather than general intellectual outcome alone, to obtain a better distinction of the specific cognitive weaknesses associated with preterm birth. D Early Human Development (2007) 83, 247 -254 a v a i l a b l e a t w w w . s c i e n c e d i r e c t . c o m w w w . e l s e v i e r . c o m / l o c a t e / e a r l h u m d e v

Evidence from animal, clinical, and imaging studies suggests that the basal ganglia and their frontal connections mediate motor inhibition, but the role of dopamine remains unclear. The aim of our study was to investigate, for the first time, whether levodopa medication influences motor inhibition and conflict resolution on the conditional stop-signal reaction time task in patients with Parkinson's disease (PD) tested on or off their medication. Sixteen PD patients and 17 healthy controls performed the conditional stop-signal reaction time (SSRT) task, which requires inhibition of responses when a stop signal is presented on "critical" trials. Additionally, on "non-critical" trials, participants are instructed to ignore the stop signal and respond, thus generating conflict between motor inhibition and initiation; and conflict-induced slowing (CIS) on these "non-critical" trials. Levodopa medication did not significantly influence response initiation, inhibition (SSRT) or the measure of conflict resolution (CIS). Compared to healthy controls, PD patients showed significantly worse response initiation and inhibition both on and off their levodopa medication. Our results suggest that motor inhibition or conflict-induced slowing on the conditional stop-signal RT task are not altered by dopamine replacement in PD. This conclusion is consistent with evidence from animal studies and clinical pharmacological investigations suggesting a role for noradrenaline in motor inhibition and impulsivity.

Many studies conducted in a laboratory or university setting are limited by funding, personnel, space, and time constraints. In the present study, we introduce a method of data collection using a mobile application that circumvents these typical experiment administration issues. Using the application, we examined cross-sectional age differences in cognitive function. We obtained data from more than 15,000 participants and replicated specific patterns of age-related differences in cognition. Using a subset of these ...

Achieving progress in understanding the cause, nature, and treatment of autism requires an integration of concepts, approaches, and empirical findings from genetic, cognitive neuroscience, animal, and clinical studies. The need for such integration has been a fundamental tenet of the discipline of developmental psychopathology from its inception. It is likely that the discovery of autism susceptibility genes will depend on the development of dimensional measures of broader phenotype autism traits. It is argued that knowledge of the cognitive neuroscience of social and language behavior will provide a useful framework for defining such measures. In this article, the current state of knowledge of the cognitive neuroscience of social and language impairments in autism is reviewed. Following from this, six candidate broader phenotype autism traits are proposed: (a) face processing, including structural encoding of facial features and face movements, such as eye gaze; (b) social affiliat...

Background-Self-efficacy and the use of self-regulatory strategies are consistently associated with physical activity behavior. Similarly, behavioral inhibition and cognitive resource allocation, indices of executive control function, have also been associated with this health behavior.

Would it be helpful to inform a driver about when a conflicting traffic situation is going to occur? We tested whether temporal orienting of attention could enhance executive control to select among conflicting stimuli and responses. Temporal orienting was induced by presenting explicit cues predicting the most probable interval for target onset, which could be short (400 ms) or long (1,300 ms). Executive control was measured both by flanker and Simon tasks involving conflict between incompatible responses and by the spatial Stroop task involving conflict between perceptual stimulus features. The results showed that temporal orienting facilitated the resolution of perceptual conflict by reducing the spatial Stroop effect, whereas it interfered with the resolution of response conflict by increasing flanker and Simon effects. Such opposite effects suggest that temporal orienting of attention modulates executive control through dissociable mechanisms, depending on whether the competition between conflicting representations is located at perceptual or response levels.

Schizophrenia patients with obsessive-compulsive disorder (OCD) may be a subgroup of schizophrenia, and OCD patients with poor insight may show psychotic-like symptoms. The aim of this work is to compare the neuropsychological performance of those patients with ...

We used exploratory and confirmatory statistical approaches to study the severity of neuropsychological (NP) impairment in 42 crack/cocaine addicted subjects and in 112 comparison subjects (40 alcoholics and 72 controls). Twenty neuropsychological test indices most reliably defining predetermined cognitive domains were submitted to exploratory factor analysis. A four-dimensional model of neurocognitive function was derived: Verbal Knowledge, Visual Memory, Verbal Memory, and Attention/Executive functioning accounted for 63% of the variance. We then examined this model's association with resting glucose metabolism in the brain reward circuit measured with 2-deoxy-2[ 18 F]fluoro-d-glucose positron emission tomography. Results revealed that (1) cocaine addicted individuals had a generalized mild level of neurocognitive impairment (<1 S.D. below control mean); and (2) controlling for age and education, relative metabolism in the dorsolateral prefrontal cortex significantly predicted the Visual Memory and Verbal Memory factors and relative metabolism in the anterior cingulate gyrus significantly predicted the Attention/Executive factor. Nevertheless, it remains to be determined whether metabolic changes in these regions are associated with addiction. Our results also suggest that compared to cocaine, alcohol has a more detrimental effect on Attention/Executive functioning, as assessed with traditional NP measures. We conclude that relative to other psychopathological disorders (such as schizophrenia), the severity of neuropsychological impairment in cocaine addiction is modest, albeit not indicative of the absence of neurocognitive dysfunction. The impact of such small differences in performance on quality of life, and possibly on craving and relapse, may be substantial. Tasks that simulate real-life decision-making or that target specific putative cognitive-behavioral or motivational-emotional mechanisms might offer greater sensitivity in characterizing the changes that accompany addiction to drugs. Obtaining valid estimates of alcohol use in cocaine addicted subjects is essential in characterizing neurocognitive functioning in individuals addicted to drugs.

In the FXS full mutation this single-gene defect results in reduced or absent FMR-1 protein (FMRP) expression (Koukoui & Chaudhuri, 2007). FMRP is argued to be specifically involved in synaptic and dendritical refinement during early brain development (Christie, Akins, Schwob, & Fallon, 2009). Absence of FMRP is primarily associated with abnormal maturation of synaptic connectivity (Oostra & Chiurazzi, 2001), and is argued to be the primary cause of the cognitive deficits frequently observed in FXS (Loesch, Huggins, & Hagerman, 2004; Visootsak, Warren, Anido, & Graham, 2005). Although the cognitive profile of FXS males has been extensively studied over the years, little is known about the relation between performance level and cognitive profile. The goal of the present study was: (a) to examine the cognitive profile of FXS full mutation males of different performance levels over a wide range of cognitive abilities; and (b) to investigate whether such a cognitive profile would be similar for FXS males of different levels of performance.

The present study examined how the updating, inhibiting, and shifting abilities underlying executive control influence spoken noun-phrase production. Previous studies provided evidence that updating and inhibiting, but not shifting, influence picture-naming response time (RT). However, little is known about the role of executive control in more complex forms of language production like generating phrases. We assessed noun-phrase production using picture description and a picture-word interference procedure. We measured picture description RT to assess length, distractor, and switch effects, which were assumed to reflect, respectively, the updating, inhibiting, and shifting abilities of adult participants. Moreover, for each participant we obtained scores on executive control tasks that measured verbal and nonverbal updating, nonverbal inhibiting, and nonverbal shifting. We found that both verbal and nonverbal updating scores correlated with the overall mean picture description RTs. Furthermore, the length effect in the RTs correlated with verbal but not nonverbal updating scores, while the distractor effect correlated with inhibiting scores. We did not find a correlation between the switch effect in the mean RTs and the shifting scores. However, the shifting scores correlated with the switch effect in the normal part of the underlying RT distribution. These results suggest that updating, inhibiting, and shifting each influence the speed of phrase production, thereby demonstrating a contribution of all three executive control abilities to language production.

Recent research in instrumental conditioning has focused on the striatum, particularly the role of the dorsal striatum in the learning processes that contribute to instrumental performance in rats. This research has found evidence of what appear to be parallel, functionally and anatomically distinct circuits involving dorsomedial striatum (DMS) and dorsolateral striatum (DLS) that contribute to two independent instrumental learning processes. Evidence suggests that the formation of the critical action-outcome associations mediating goal-directed action are localized to the dorsomedial striatum, whereas the sensorimotor connections that control the performance of habitual actions are localized to the dorsolateral striatum. In addition to the dorsal striatum, these learning processes appear to engage distinct corticostriatal networks and to be embedded in a complex of converging and partially segregated loops that constitute the cortico-striatal thalamo-cortical feedback circuit. As the entry point for the basal ganglia, cortical circuits involving the dorsal striatum are clearly in a position to control a variety of motor functions but, as recent studies of various neurodegenerative disorders have made clear, they are also involved in a number of cognitive and executive functions including action selection, planning, and decision-making.

Cerebellar pathology commonly shows important motor signs and less evident cognitive dysfunction. The ’cerebellar cognitive affective syndrome’ is characterised by impairment on executive function, spatial cognition, language and behaviour. We report the case of a man with acute onset of transitory motor features and severe mental disorders. Cranial CT and brain MRI revealed extended cerebellar lesions. Neuropsychological assessment disclosed deficits of attention, executive function and memory. Auditory event–related potentials showed abnormal P300. These data suggest a pure “cerebellar cognitive affective syndrome” and strengthen the hypothesis of cerebellar cognitive function modulation.

Background. Acute disseminated encephalomyelitis is an acute, inflammatory-demyelinating disorder of the central nervous system usually with monophasic course and a favourable neurological outcome. Longterm neurocognitive sequelae and quality of life have not been fully investigated yet.

The current study evaluated the discriminant validity and homogeneity of category fluency, Stroop interference, and planning measures of executive dysfunction and introduced a new measure of planning behavior. We compared performance of patients with schizophrenia, Parkinson 's disease, and Huntington's disease, which are disorders associated with some impairment of executive function. Findings intricated that all three measures successfully discriminated between patient groups and controis. Correlational analysis suggested a strong association between test scores on these measures, which were only moderately related to performance on nonexecutive function measures. It is concluded that the three tasks are sensitive and relatively homogeneous in their recruitment of executive functions.

Cognitive problems in persons with epilepsy manifest over a lifetime; however, whether abnormal cognition in an individual with epilepsy is a result of comorbid brain substrate, the epilepsy itself or its underlying etiology, the antiepileptic agents used to control it, or a combination of these and other factors remains controversial. There is a continuing need for improved therapies to control seizures and reduce the incidence of adverse events, especially those involving the central nervous system that compromise attention, intelligence, language skills, verbal and nonverbal memory, executive function, and psychomotor speeds. Although cognitive decline typically occurs among patients with more severe epilepsy, physicians must judiciously select therapy with an eye toward not only controlling seizures but also ensuring that all patients retain as much function as possible throughout their lives.

BACKGROUND AND RELATED WORK Department of Veterans Affairs  Polytrauma Centers The signature injuries of soldiers returning from Afghanistan and Iraq are polytrauma and TBI [5-6]. In the majority of Department of Veterans Affairs (VA) clinical cases, polytrauma and TBI are caused by blast injuries from improvised explosive devices, although TBI also results from noncombat events such as motor vehicle accidents. Polytrauma is defined as injuries to two or more body systems from one event. An extreme example would be injuries that simultaneously result in limb amputation, TBI, burns, deafness, and blindness, with long-term physical and cognitive impairments and functional disabilities.

There are marked disparities between pre-school children in key skills affecting school readiness, disparities that commonly persist and influence children&#39;s later academic achievements, employment, and adjustment. Much of this disparity is linked to socio-economic disadvantage and its impact on the home learning environment. Children&#39;s Centres are an ideal context in which to implement and evaluate programmes to address this problem. They principally serve the 30% worst areas on the Indices of Deprivation Affecting Children, providing for families from the antenatal period up to age 5 years, aiming to promote parenting skills and provide care for children. We are conducting a randomised controlled trial, based in Children Centres, to evaluate a parenting intervention for caregivers of children between 28 and 45 months of age. The intervention provides training to parents in dialogic book-sharing. The training is run by a facilitator who sees parents in small groups, on a we...

Background: Epidemiologic evidence regarding niacin, folate, vitamin B-6, and vitamin B-12 intake in relation to cognitive function is limited, especially in midlife.Objective: We hypothesize that higher intake of these B vitamins in young adulthood is associated with better cognition later in life.Design: This study comprised a community-based multicenter cohort of black and white men and women aged 18-30 y in 1985-1986 (year 0, i.e., baseline) from the Coronary Artery Risk Development in Young Adults (CARDIA) study (n = 3136). We examined participants&#39; CARDIA diet history at years 0, 7, and 20 to assess nutrient intake, including dietary and supplemental B vitamins. We measured cognitive function at year 25 (mean ± SD age: 50 ± 4 y) through the use of the Rey Auditory Verbal Learning Test (RAVLT) for verbal memory, the Digit Symbol Substitution Test (DSST) for psychomotor speed, and a modified Stroop interference test for executive function. Higher RAVLT and DSST scores and a ...

Cognitive and behavioral problems after pediatric traumatic brain injury lead to poor functioning across multiple settings and can persist long-term after injury. Executive dysfunction is particularly common; however, there is a paucity of evidence-based interventions to guide treatment. WHAT THIS STUDY ADDS: This study is among the largest randomized controlled trials performed in pediatric traumatic brain injury. It demonstrates the ability to use an online problemsolving-based intervention to improve caregiver ratings of executive dysfunction within 12 months after injury. abstract OBJECTIVE: Executive dysfunction after traumatic brain injury (TBI) in children is common and leads to significant problems in functioning across multiple settings. The objective of this study was to evaluate the efficacy of a web-based counselor-assisted problem solving (CAPS) intervention compared with an Internet resource comparison (IRC) for treatment of executive dysfunction within 12 months after complicated mild to severe TBI in adolescents. We hypothesized that CAPS would significantly improve parent ratings of executive dysfunction compared with an IRC. METHODS: Participants included 132 adolescents aged 12 to 17 years who sustained a complicated mild to severe TBI within 1 to 6 months before study enrollment. Study design was a multisite, assessorblinded, randomized controlled trial. Study sites included 3 tertiary pediatric hospitals and 2 tertiary general medical centers. The main outcome measure was primary caregiver Behavioral Rating Inventory of Executive Function Global Executive Composite at baseline and 6-month follow-up. Generalized linear models that controlled for baseline scores were used to compare the CAPS and IRC scores. RESULTS: In older teens, the CAPS group showed significant improvement in executive function behaviors at 6-month follow-up compared with the IRC group (F = 6.74, P = .01, Cohen' s d = 0.63). CONCLUSIONS: Findings indicate that web-based CAPS improves primary caregiver-rated executive functioning within the first 12 months after TBI in older adolescents. Future research needs to define the optimal timing after injury for delivery of CAPS and characteristics of individuals and families who are most likely to benefit from CAPS.

Phishing is the spoofing of Internet websites or emails aimed at tricking users into entering sensitive information, with such goals as financial or identity theft. The current study sought to determine whether age is associated with increased susceptibility to phishing and whether tests of executive functioning can predict phishing susceptibility. A total of 193 cognitively intact participants, 91 younger adults and 102 older adults, were primarily recruited through a Psychology department undergraduate subject pool and a gerontology research registry, respectively. The Executive Functions Module from the Neuropsychological Assessment Battery and the Iowa Gambling Task were the primary cognitive predictors of reported phishing suspiciousness. Other predictors included age group (older vs. younger), sex, education, race, ethnicity, prior knowledge of phishing, prior susceptibility to phishing, and whether or not browsing behaviors were reportedly different in the laboratory setting ...

Cannabis use is highly prevalent among people with schizophrenia, and coupled with impaired cognition, is thought to heighten the risk of illness onset. However, while heavy cannabis use has been associated with cognitive deficits in long-term users, studies among patients with schizophrenia have been contradictory. This article consists of 2 studies. In Study I, a meta-analysis of 10 studies comprising 572 patients with established schizophrenia (with and without comorbid cannabis use) was conducted. Patients with a history of cannabis use were found to have superior neuropsychological functioning. This finding was largely driven by studies that included patients with a lifetime history of cannabis use rather than current or recent use. In Study II, we examined the neuropsychological performance of 85 patients with first-episode psychosis (FEP) and 43 healthy nonusing controls. Relative to controls, FEP patients with a history of cannabis use (FEP 1 CANN; n 5 59) displayed only selective neuropsychological impairments while those without a history (FEP 2 CANN; n 5 26) displayed generalized deficits. When directly compared, FEP 1 CANN patients performed better on tests of visual memory, working memory, and executive functioning. Patients with early onset cannabis use had less neuropsychological impairment than patients with later onset use. Together, these findings suggest that patients with schizophrenia or FEP with a history of cannabis use have superior neuropsychological functioning compared with nonusing patients. This association between better cognitive performance and cannabis use in schizophrenia may be driven by a subgroup of ''neurocognitively less impaired'' patients, who only developed psychosis after a relatively early initiation into cannabis use.

Analyses of language production of individuals with traumatic brain injury (TBI) place increasing emphasis on microlinguistic (i.e., within-sentence) patterns. It is unknown whether the observed problems involve implementation of well-formed sentence frames or represent a fundamental linguistic disturbance in computing sentence structure. This study investigated the cognitive basis for microlinguistic deficits in individuals with TBI. Fifteen nonaphasic individuals with severe TBI and 6 age- and education-matched non brain-injured adults participated in this study. Monologic discourse samples were analyzed for pausing patterns, mazes, errors, and abandoned utterances. Measures of cognitive abilities were correlated with the sentence measures. The speakers with TBI produced more pauses between clauses (but not within clauses) as well as more mazes than did the non brain-injured speakers. Significant regression models were built. Raven&amp;amp;amp;amp;amp;amp;amp;#39;s Coloured Progressive Matrices (Raven, 1965), a measure associated with working memory, predicted pause behavior, and Likenesses-Differences (Baker &amp;amp;amp;amp;amp;amp;amp;amp; Leland, 1967), a measure of executive function, predicted maze behavior. Sentence planning impairments following TBI are associated with deficient organization and monitoring of language representations in working memory. These findings suggest that the deficits are due to problems in the recruitment and control of attention for sentence planning. These findings bear on sentence processing models that emphasize the activation, organization, and maintenance of language representations for accurate sentence production.