The association between early childhood onset epilepsy and attention-deficit hyperactivity disorder (ADHD) in 3237 children and adolescents with Autism Spectrum Disorder (ASD): a historical longitudinal cohort data linkage study.

Children and young people with Autism Spectrum Disorder (ASD) have an increased risk of comorbidities, such as epilepsy and Attention-Deficit/Hyperactivity Disorder (ADHD). However, little is known about the relationship between early childhood epilepsy (below age 7) and later ADHD diagnosis (at age 7 or above) in ASD. In this historical cohort study, we examined this relationship using an innovative data source, which included linked data from routinely collected acute hospital paediatric records and childhood community and inpatient psychiatric records. In a large sample of children and young people with ASD (N = 3237), we conducted a longitudinal analysis to examine early childhood epilepsy as a risk factor for ADHD diagnosis while adjusting for potential confounders, including socio-demographic characteristics, intellectual disability, family history of epilepsy and associated physical conditions. We found that ASD children and young people diagnosed with early childhood epilepsy had nearly a twofold increase in risk of developing ADHD later in life, an association which persisted after adjusting for potential confounders (adjusted OR = 1.72, CI95% = 1.13-2.62). This study suggests that sensitive monitoring of ADHD symptoms in children with ASD who have a history of childhood epilepsy may be important to promote early detection and treatment. It also highlights how linked electronic health records can be used to examine potential risk factors over time for multimorbidity in neurodevelopmental conditions.

COVID-19-related school closures and patterns of hospital admissions with stress-related presentations in secondary school-aged adolescents: weekly time series.

This study examines health service indicators of stress-related presentations (relating to pain, mental illness, psychosomatic symptoms and self-harm) in adolescents of secondary school age, using Hospital Episode Statistics data for England. We examined weekly time series data for three academic years spanning the time before (2018-2019) and during the COVID-19 pandemic (2019-2020 and 2020-2021), including the first lockdown when schools were closed to the majority of pupils. For all secondary school children, weekly stress presentations dropped following school closures. However, patterns of elevated stress during school terms re-established after reopening, with girls aged 11-15 showing an overall increase compared with pre-pandemic rates.

Broad white matter impairment in multiple system atrophy.

Multiple system atrophy (MSA) is a rare neurodegenerative disorder characterized by the widespread aberrant accumulation of α-synuclein (α-syn). MSA differs from other synucleinopathies such as Parkinson's disease (PD) in that α-syn accumulates primarily in oligodendrocytes, the only source of white matter myelination in the brain. Previous MSA imaging studies have uncovered focal differences in white matter. Here, we sought to build on this work by taking a global perspective on whole brain white matter. In order to do this, in vivo structural imaging and diffusion magnetic resonance imaging were acquired on 26 MSA patients, 26 healthy controls, and 23 PD patients. A refined whole brain approach encompassing the major fiber tracts and the superficial white matter located at the boundary of the cortical mantle was applied. The primary observation was that MSA but not PD patients had whole brain deep and superficial white matter diffusivity abnormalities (p < .001). In addition, in MSA patients, these abnormalities were associated with motor (Unified MSA Rating Scale, Part II) and cognitive functions (Mini-Mental State Examination). The pervasive whole brain abnormalities we observe suggest that there is widespread white matter damage in MSA patients which mirrors the widespread aggregation of α-syn in oligodendrocytes. Importantly, whole brain white matter abnormalities were associated with clinical symptoms, suggesting that white matter impairment may be more central to MSA than previously thought.

Brain and behavioral correlates of insulin resistance in youth with depression and obesity.

Depression, together with insulin resistance, is increasingly prevalent among youth. These conditions have traditionally been compartmentalized, but recent evidence suggests that a shared brain motivational network underlies their co-occurrence. We posit that, in the context of depressive symptoms, insulin resistance is associated with aberrant structure and functional connectivity in the Anterior Cingulate Cortex (ACC) and hippocampus. This motivational neural circuit underlies dysfunctional behavioral responses and increased sensitivity to rewarding aspects of ingesting high calorie food that lead to disinhibition of eating even when satiated. To investigate this shared mechanism, we evaluated a sample of forty-two depressed and overweight (BMI > 85th%) youth aged 9 to 17. Using ACC and hippocampus structural and seed-based regions of interest, we investigated associations between insulin resistance, depression, structure (ACC thickness, and ACC and hippocampal area), and resting-state functional connectivity (RSFC). We predicted that aberrant associations among these neural and behavioral characteristics would be stronger in insulin resistant compared to insulin sensitive youth. We found that youth with greater insulin resistance had higher levels of anhedonia and more food seeking behaviors, reduced hippocampal and ACC volumes, and greater levels of ACC and hippocampal dysconnectivity to fronto-limbic reward networks at rest. For youth with high levels of insulin resistance, thinner ACC and smaller hippocampal volumes were associated with more severe depressive symptoms, whereas the opposite was true for youth with low levels of insulin resistance. The ACC-hippocampal motivational network that subserves depression and insulin resistance separately, may represent a critical neural interaction that link these syndromes together.

Superficial white matter damage in anti-NMDA receptor encephalitis.

BACKGROUND: Clinical brain MRI is normal in the majority of patients with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis. However, extensive deep white matter damage wasrecently identifiedin these patients using diffusion weighted imaging. Here, our aim was to study a particularly vulnerable brain compartment, the late myelinating superficial white matter. METHODS: Forty-six patients with anti-NMDAR encephalitis were included. Ten out of these were considered neurologically recovered (modified Rankin scale of zero), while 36 patients were non-recovered. In addition, 30 healthy controls were studied. MRI data were collected from all subjects and superficial white matter mean diffusivity derived from diffusion tensor imaging was compared between groups in whole brain, lobar and vertex-based analyses. Patients underwent comprehensive cognitive testing, and correlation analyses were performed between cognitive performance and superficial white matter integrity. RESULTS: Non-recovered patients showed widespread superficial white matter damage in comparison to recovered patients and healthy controls. Vertex-based analyses revealed that damage predominated in frontal and temporal lobes. In contrast, the superficial white matter was intact in recovered patients. Importantly, persistent cognitive impairments in working memory, verbal memory, visuospatial memory and attention significantly correlated with damage of the superficial white matter in patients. CONCLUSIONS: Anti-NMDAR encephalitis is associated with extensive superficial white matter damage in patients with incomplete recovery. The strong association with impairment in several cognitive domains highlights the clinical relevance of white matter damage in this disorder and warrants investigations of the underlying pathophysiological mechanisms.

Insulin resistance is associated with smaller brain volumes in a preliminary study of depressed and obese children.

OBJECTIVE: During childhood, the brain can consume up to 65% of total calories, and a steady supply of the brain's main fuel glucose needs to be maintained. Although the brain itself is not dependent on insulin for the uptake of glucose, insulin plays an important role in energy homeostasis. Thus, the risk for insulin resistance during brain development may negatively impact the whole brain volume. METHODS: We investigated the link between the insulin resistance and the whole brain volume as measured by structural Magnetic resonance imaging (MRI) in 46 unmedicated depressed and overweight youths between the ages of 9 and 17 years. RESULTS: Smaller whole brain volumes were associated with insulin resistance independent of age, sex, depression severity, body mass index, socioeconomic status, Tanner Stage, and Intelligence quotient (IQ) (r = 0.395, P = .014) CONCLUSIONS: There may be a significant cost for developing insulin resistance on the developing brain. Disentangling the precise relationship between the insulin resistance and the developing brain is critical.

The superficial white matter in Alzheimer's disease.

White matter abnormalities have been shown in the large deep fibers of Alzheimer's disease patients. However, the late myelinating superficial white matter comprised of intracortical myelin and short-range association fibers has not received much attention. To investigate this area, we extracted a surface corresponding to the superficial white matter beneath the cortex and then applied a cortical pattern-matching approach which allowed us to register and subsequently sample diffusivity along thousands of points at the interface between the gray matter and white matter in 44 patients with Alzheimer's disease (Age: 71.02 ± 5.84, 16M/28F) and 47 healthy controls (Age 69.23 ± 4.45, 19M/28F). In patients we found an overall increase in the axial and radial diffusivity across most of the superficial white matter (P < 0.001) with increases in diffusivity of more than 20% in the bilateral parahippocampal regions and the temporal and frontal lobes. Furthermore, diffusivity correlated with the cognitive deficits measured by the Mini-Mental State Examination scores (P < 0.001). The superficial white matter has a unique microstructure and is critical for the integration of multimodal information during brain maturation and aging. Here we show that there are major abnormalities in patients and the deterioration of these fibers relates to clinical symptoms in Alzheimer's disease.

Selective Cognitive Dysfunction Is Related to a Specific Pattern of Cerebral Damage in Persons With Severe Traumatic Brain Injury.

OBJECTIVE: Cognitive dysfunction is a common sequela of traumatic brain injury (TBI); indeed, patients show a heterogeneous pattern of cognitive deficits. This study was aimed at investigating whether patients who show selective cognitive dysfunction after TBI present a selective pattern of cerebral damage. SETTING: Post-Coma Unit, IRCCS Santa Lucia Foundation, Rome, Italy. PARTICIPANTS: We collected data from 8 TBI patients with episodic memory disorder and without executive deficits, 7 patients with executive function impairment and preserved episodic memory capacities, and 16 healthy controls. DESIGN: We used 2 complementary analyses: (1) an exploratory and qualitative approach in which we investigated the distribution of lesions in the TBI groups, and (2) a hypothesis-driven and quantitative approach in which we calculated the volume of hippocampi of individuals in the TBI and control groups. MAIN MEASURES: Neuropsychological scores and hippocampal volumes. RESULTS: We found that patients with TBI and executive functions impairment presented focal lesions involving the frontal lobes, whereas patients with TBI and episodic memory disorders showed atrophic changes of the mesial temporal structure (hippocampus). CONCLUSION: The complexity of TBI is due to several heterogeneous factors. Indeed, studying patients with TBI and selective cognitive dysfunction should lead to a better understanding of correlations with specific brain impairment and damage, better follow-up of long-term outcome scenarios, and better planning of selective and focused rehabilitation programs.

Three-dimensional surface deformation-based shape analysis of hippocampus and caudate nucleus in children with fetal alcohol spectrum disorders.

Surface deformation-based analysis was used to assess local shape variations in the hippocampi and caudate nuclei of children with fetal alcohol spectrum disorders. High-resolution structural magnetic resonance imaging images were acquired for 31 children (19 controls and 12 children diagnosed with fetal alcohol syndrome/partial FAS). Hippocampi and caudate nuclei were manually segmented, and surface meshes were reconstructed. An iterative closest point algorithm was used to register the template of one control subject to all other shapes in order to capture the true geometry of the shape with a fixed number of landmark points. A point distribution model was used to quantify the shape variations in terms of a change in co-ordinate positions. Using the localized Hotelling T(2) method, regions of significant shape variations between the control and exposed subjects were identified and mapped onto the mean shapes. Binary masks of hippocampi and caudate nuclei were generated from the segmented volumes of each brain. These were used to compute the volumes and for further statistical analysis. The Mann-Whitney test was performed to predict volume differences between the groups. Although the exposed and control subjects did not differ significantly in their volumes, the shape analysis showed the hippocampus to be more deformed at the head and tail regions in the alcohol-exposed children. Between-group differences in caudate nucleus morphology were dispersed across the tail and head regions. Correlation analysis showed associations between the degree of compression and the level of alcohol exposure. These findings demonstrate that shape analysis using three-dimensional surface measures is sensitive to fetal alcohol exposure and provides additional information than volumetric measures alone.

Superficial white matter integrity in neuromyelitis optica spectrum disorder and multiple sclerosis.

Background: Superficial white matter (SWM) is a particularly vulnerable area of white matter adjacent to cerebral cortex that was shown to be a sensitive marker of disease severity in several neurological and psychiatric disorders, including multiple sclerosis (MS), but has not been studied in neuromyelitis optica spectrum disorder (NMOSD). Objective: To compare the integrity of SWM between MS patients, NMOSD patients and healthy controls, and explore the correlation of SWM integrity with cognitive performance and overall disability. Methods: Forty NMOSD patients, 48 MS patients and 52 healthy controls were included in the study. Mean diffusivity (MD) values obtained by diffusion tensor imaging were used as a measure of SWM integrity. Cognitive performance and overall disability were assessed with standardized tests. Results: Superficial white matter MD was increased in MS patients compared to healthy controls. Higher MD was associated with poorer spatial memory (most prominently in right temporal and right limbic lobe) and poorer information processing speed in MS patients. After adjusting for age, no significant differences of SWM MD were observed between NMOSD patients and healthy controls. Conclusion: Integrity of SWM is compromised in MS, but not in NMOSD, and can serve as a sensitive marker of disease severity.

Reciprocal developmental pathways between future-related thinking and symptoms of adolescent depression and anxiety: A systematic review and meta-analysis of longitudinal studies.

Adolescence is a time when important decisions about the future are made and vulnerability to mental health problems increases. We reviewed longitudinal studies examining the reciprocal pathways between future-related thinking (hopelessness, hope, optimism/positive future expectations) and adolescent depression and anxiety symptoms. Evidence from 22 studies (N = 10,682) found that negative future-related thinking predicted subsequent depression (r = 0.27, p < .001), an effect still significant after controlling for baseline depression (r = 0.23, p < .001). Higher hopelessness (r = 0.34, p < .001), lower hope (r = 0.16, p < .001), and reduced optimism/positive future expectations (r = 0.18, p < .001) were associated with subsequently increased depressive symptoms. Negative future-related thinking also predicted later increased anxiety symptoms (r = 0.15, p = .021). Concerning the reciprocal pathway, depressive symptoms were associated with later negative future-related thinking (r = 0.32, p < .001), which remained after baseline levels of future-related thinking were controlled (r = 0.07, p = .02). There were insufficient studies to infer reciprocal links between anxiety and future-related thinking. Our analyses provided evidence of a reciprocal developmental relationship between depressive symptoms and future-related thinking, implying a negative cycle. Identifying precursors of this cycle could provide the basis for depression prevention in adolescents and promote better decision-making about the future.

Relationships between gray matter, body mass index, and waist circumference in healthy adults.

Obesity and overweight are often defined by the body mass index (BMI), which associates with metabolic and cardiovascular disease, and possibly with dementia as well as variations in brain volume. However, body fat distribution and abdominal obesity (as measured by waist circumference) is more strongly correlated with cardiovascular and metabolic risk than is BMI. While prior studies have revealed negative associations between gray matter tissue volumes and BMI, the relationship with respect to waist circumference remains largely unexplored. We therefore investigated the effects of both BMI and waist circumference on local gray matter volumes in a group of 115 healthy subjects screened to exclude physical or mental disorders that might affect the central nervous system. Results revealed significant negative correlations for both BMI and waist circumference where regional gray matter effects were largest within the hypothalamus and further encompassed prefrontal, anterior temporal and inferior parietal cortices, and the cerebellum. However, associations were more widespread and pronounced for waist circumference than BMI. Follow-up analyses showed that these relationships differed significantly across gender. While associations were similar for both BMI and waist circumference for males, females showed more extensive correlations for waist circumference. Our observations suggest that waist circumference is a more sensitive indicator than BMI, particularly in females, for potentially determining the adverse effects of obesity and overweight on the brain and associated risks to health.

Global and regional alterations of hippocampal anatomy in long-term meditation practitioners.

Studies linking meditation and brain structure are still relatively sparse, but the hippocampus is consistently implicated as one of the structures altered in meditation practitioners. To explore hippocampal features in the framework of meditation, we analyzed high-resolution structural magnetic resonance imaging data from 30 long-term meditators and 30 controls, closely matched for sex, age, and handedness. Hippocampal formations were manually traced following established protocols. In addition to calculating left and right hippocampal volumes (global measures), regional variations in surface morphology were determined by measuring radial distances from the hippocampal core to spatially matched surface points (local measures). Left and right hippocampal volumes were larger in meditators than in controls, significantly so for the left hippocampus. The presence and direction of this global effect was confirmed locally by mapping the exact spatial locations of the group differences. Altogether, radial distances were larger in meditators compared to controls, with up to 15% difference. These local effects were observed in several hippocampal regions in the left and right hemisphere though achieved significance primarily in the left hippocampal head. Larger hippocampal dimensions in long-term meditators may constitute part of the underlying neurological substrate for cognitive skills, mental capacities, and/or personal traits associated with the practice of meditation. Alternatively, given that meditation positively affects autonomic regulation and immune activity, altered hippocampal dimensions may be one result of meditation-induced stress reduction. However, given the cross-sectional design, the lack of individual stress measures, and the limited resolution of brain data, the exact underlying neuronal mechanisms remain to be established.

Young people's future thinking and mental health: The development and validation of the Adolescent Future Thinking Rating Scale.

OBJECTIVES: We aimed to develop and validate a new scale of future thinking and adolescent mental health-the Adolescent Future Thinking Rating Scale (AFTRS). METHODS: A provisional AFTRS was developed from interviews with 19 adolescents. It was completed by three samples: exploratory (n = 161) aged 16-21 years, who also completed established measures of future thinking, cognitive risk factors, depression and anxiety; replication (n = 209) aged 16-25 years; and test-retest (n = 102) aged 17-23 years. The reliability, convergent, predictive, and discriminant validity were examined. RESULTS: Exploratory factor analyses identified the AFTRS-18 and AFTRS-12. Both had three sub-scales: (i) Concerns about Maladaptive Future Thinking, (ii) Future Positivity, and (iii) Ability to Visualise the Future. Established future thinking measures were combined into two factors: Negative Future Emotions (Cognitive Triad Inventory-View of Future and Beck's Hopelessness Scale) and Immediacy Preference (Consideration of Future Consequences and Quick Delay Questionnaire). The AFTRS-18 and AFTRS-12 were similarly associated with both factors and with depression/anxiety. Internal consistency and test-retest reliability were high. CONCLUSIONS: The AFTRS-12 and AFTRS-18 are reliable and valid measures of the three key dimensions of adolescent future thinking and mental health. The first subscale remained significant in predicting depression and anxiety after controlling for general cognitive risks.

Links between mental health problems and future thinking from the perspective of adolescents with experience of depression and anxiety: a qualitative study.

BACKGROUND: Depression and anxiety are common during adolescence and could have detrimental impacts on young people's ability to make and implement plans for their future. However, to the best of our knowledge, no other study has adopted a qualitative approach in investigating these effects from the perspective of adolescents with lived experiences of depression and anxiety. We sought to understand how young people perceive and interpret the impact of mental health conditions on their thinking about the future. METHODS: We conducted semi-structured interviews with 19 adolescents aged 16-19 years in the UK (median age = 19, IQR = 1.5), who had a history of protracted periods of clinical or subclinical depression and/or anxiety. They were asked to reflect on how their ability to think about the future and the content of the future-related thinking was impacted during periods of poor mental health, compared with periods of feeling well. Interviews were transcribed verbatim and subjected to thematic content analysis. RESULTS: Five domains were identified. First, the impact of mood on future thinking capability focuses on reduced ability and motivation to engage in future thinking. Second, the impact of mood on images, thoughts, and feelings about the future includes the emotional valence of future-related thoughts, their vividness, structure, and the extent to which they intimated subjective feelings of control (i.e., agency). Third, social influences focuses on social factors that might ameliorate or exacerbate future thinking. Fourth, reflections on personal worries and expectations about the future captures personal interpretations of past worries and hopes and how future thinking affected mood. Finally, personal coping refers to how young people cope with the negative emotions that come with future thinking. CONCLUSIONS: This study provided a nuanced and granular account of how depression and anxiety impacted young people's future thinking based on their lived experiences. By highlighting the different ways that variations in future thinking were experienced as a function of depression and anxiety, our analysis highlighted new factors that should be considered in studies of adolescent mental health risk, which could inform the development of new therapeutic approaches.

Bridging the hemispheres in meditation: thicker callosal regions and enhanced fractional anisotropy (FA) in long-term practitioners.

Recent findings suggest a close link between long-term meditation practices and the structure of the corpus callosum. Prior analyses, however, have focused on estimating mean fractional anisotropy (FA) within two large pre-defined callosal tracts only. Additional effects might exist in other, non-explored callosal regions and/or with respect to callosal attributes not captured by estimates of FA. To further explore callosal features in the framework of meditation, we analyzed 30 meditators and 30 controls, carefully matched for sex, age, and handedness. We applied a multimodal imaging approach using diffusion tensor imaging (DTI) in combination with structural magnetic resonance imaging (MRI). Callosal measures of tract-specific FA were complemented with other global (segment-specific) estimates as well as extremely local (point-wise) measures of callosal micro- and macro-structure. Callosal measures were larger in long-term meditators compared to controls, particularly in anterior callosal sections. However, differences achieved significance only when increasing the regional sensitivity of the measurement (i.e., using point-wise measures versus segment-specific measures) and were more prominent for microscopic than macroscopic characteristics (i.e., callosal FA versus callosal thickness). Thicker callosal regions and enhanced FA in meditators might indicate greater connectivity, possibly reflecting increased hemispheric integration during cerebral processes involving (pre)frontal regions. Such a brain organization might be linked to achieving characteristic mental states and skills as associated with meditation, though this hypothesis requires behavioral confirmation. Moreover, longitudinal studies are required to address whether the observed callosal effects are induced by meditation or constitute an innate prerequisite for the start or successful continuation of meditation.

Disease and genetic contributions toward local tissue volume disturbances in schizophrenia: a tensor-based morphometry study.

Structural brain deficits, especially frontotemporal volume reduction and ventricular enlargement, have been repeatedly reported in patients with schizophrenia. However, it remains unclear whether brain structural deformations may be attributable to disease-related or genetic factors. In this study, the structural magnetic resonance imaging data of 48 adult-onset schizophrenia patients, 65 first-degree nonpsychotic relatives of schizophrenia patients, 27 community comparison (CC) probands, and 73 CC relatives were examined using tensor-based morphometry (TBM) to isolate global and localized differences in tissue volume across the entire brain between groups. We found brain tissue contractions most prominently in frontal and temporal regions and expansions in the putamen/pallidum, and lateral and third ventricles in schizophrenia patients when compared with unrelated CC probands. Results were similar, though less prominent when patients were compared with their nonpsychotic relatives. Structural deformations observed in unaffected patient relatives compared to age-similar CC relatives were suggestive of schizophrenia-related genetic liability and were pronounced in the putamen/pallidum and medial temporal regions. Schizophrenia and genetic liability effects for the putamen/pallidum were confirmed by regions-of-interest analysis. In conclusion, TBM findings complement reports of frontal, temporal, and ventricular dysmorphology in schizophrenia and further indicate that putamen/pallidum enlargements, originally linked mainly with medication exposure in early studies, also reflect a genetic predisposition for schizophrenia. Thus, brain deformation profiles revealed in this study may help to clarify the role of specific genetic or environmental risk factors toward altered brain morphology in schizophrenia.

Callosal thickness reductions relate to facial dysmorphology in fetal alcohol spectrum disorders.

BACKGROUND: Structural abnormalities of the corpus callosum (CC), such as reduced size and increased shape variability, have been documented in individuals with fetal alcohol spectrum disorders (FASD). However, the regional specificity of altered CC structure, which may point to the timing of neurodevelopmental disturbances and/or relate to specific functional impairments, remains unclear. Furthermore, associations between facial dysmorphology and callosal structure remain undetermined. METHODS: One hundred and fifty-three participants (age range 8 to 16) including 82 subjects with FASD and 71 nonexposed controls were included in this study. The structural magnetic resonance imaging data of these subjects was collected at 3 sites (Los Angeles and San Diego, California, and Cape Town, South Africa) and analyzed using classical parcellation schemes, as well as more refined surface-based geometrical modeling methods, to identify callosal morphological alterations in FASD at high spatial resolution. RESULTS: Reductions in callosal thickness and area, specifically in the anterior third and the splenium, were observed in FASD compared with nonexposed controls. In addition, reduced CC thickness and area significantly correlated with reduced palpebral fissure length. CONCLUSIONS: Consistent with previous reports, findings suggest an adverse effect of prenatal alcohol exposure on callosal growth and further indicate that fiber pathways connecting frontal and parieto-occipital regions in each hemisphere may be particularly affected. Significant associations between callosal and facial dysmorphology provide evidence for a concurrent insult to midline facial and brain structural development in FASD.

Topographical relationships between arcuate fasciculus connectivity and cortical thickness.

The arcuate fasciculus (AF) connects cortical regions important in language processing, but how fiber coherence and organization relates to gray matter macrostructure remains uncharacterized. We used high-resolution structural and 30-direction diffusion imaging data from 36 healthy adults (24 male/12 female; mean age, 30.5 ± 9.8 years) to establish the relationships between AF microstructure and regional variations in cortical gray matter within language networks. Cortical pattern-matching algorithms were used to measure gray matter thickness at high-spatial density, and a validated diffusion tractography method was used to reconstruct the AF in the left and right hemisphere of each subject. Relationships between imaging measures and neuropsychological scores of verbal fluency were additionally assessed. Results revealed positive and highly topographical associations between arcuate fractional anisotropy (FA) and cortical thickness within anterior and posterior language regions and surrounding cortices, more prominently in the left hemisphere. These regional cortical thickness/FA relationships were primarily attributable to variations in radial diffusivity. Associations between cortical thickness and verbal fluency were observed in perisylvian language-related regions. Language scores were associated with left-hemisphere AF axial diffusivity, but not with AF FA or radial diffusivity. These findings thus suggest that particular components of white matter microstructure and regional increases in cortical thickness benefit aspects of language processing. Furthermore, the topographical relationships between independent measures of white matter and gray matter integrity suggest that rich developmental or environmental interactions influence brain structure and function where the presence and strength of such associations may elucidate pathophysiological processes influencing language systems.

The relative effectiveness of law enforcement policies aimed at reducing illegal trade: Evidence from laboratory markets.

Despite recent emphasis and implementation of national and international anti-money laundering policies, illegal product markets, and their associated illicit profit remain a global problem. In addition to law enforcement aimed at reducing money-laundering, enforcement also takes place during (1) the production (e.g. crop eradication) and (2) sale (e.g. seizure of products during transportation that interrupts buyer and seller transactions) of the illegal product. Since funds for enforcement come from limited budgets, understanding where in this production-trade-laundering cycle law enforcement is most impactful becomes a global question. Using laboratory experimental markets and a seizure rate of 20%, we find that law enforcement focused on seizing laundered profits does little to reduce illegal market activity when compared to no law enforcement, suggesting that focusing law enforcement on money laundering will likely be ineffective at reducing crime. Results further show the amount of illicit trade is nearly 32% lower when law enforcement is focused at the point of sale, and there may be additional economic incentives that reduce illicit trade in the long run when compared to no law enforcement. Enforcement at the point of production also reduces market activity, but not as effectively as enforcement at the point of sale. Lastly, the empirical findings deviate from equilibrium predictions, suggesting law enforcement policy based on theory alone may lead to inefficient allocation of limited law enforcement resources.