Microstructural white matter alterations and personality traits: A diffusion MRI study

Personality traits refer to a set of independent patterns of behaviour, cognition, and emotion. The Big-Five of Personality (NEO-FFI), is one of the most generally recognized taxonomies of personality. The current structural and functional correlates of personality are divergent and inconsistent in some cases, which necessitate further investigation of it. Herein, we aimed to investigate the white matter (WM) microstructural correlates of personality traits using diffusion MRI connectometry. Overall, the main findings of this study were located in different parts of the corpus callosum (CC) and middle cerebellar peduncle (MCP), highlighting the significant role of WM local connectome in the CC and MCP in the regulation of personality traits. Future studies need to validate our results.     

A high-field functional MRI study of quadri-lingual subjects

We assessed six multilingual subjects by functional MRI using a Noun Verb Generation task in four different languages. We hypothesised that the degree of proficiency in each language would be related to the extent of functional activity measured in a region of interest analysis. Proficiency in each language was quantified using two neuropsychological tests. All four languages activated overlapping brain areas, corresponding to the major language regions. The number of activated voxels correlated with proficiency, so that the activated volume increased for languages in which a subject had poorer proficiency. Activation did not appear to be dependent on the age at which the language was learnt.     

Neural substrates of reduced walking activity after supratentorial stroke: A voxel-based lesion symptom mapping study

BackgroundMost stroke patients exhibit low levels of walking activity, a key component of secondary stroke prevention. The predictors of walking activity may be multifactorial and are thus far partially understood. We aimed to study the neuroanatomic correlates of low levels of daily walking activity following hemispheric stroke.MethodsIn this cross-sectional study, 33 community-dwelling stroke survivors (age: 63.9 ± 12.9 years; % female: 36.4%; NIHSS at admission: 3.3 ± 4.0) were prospectively recruited at least 3 months after a first ever, unilateral, supratentorial stroke confirmed by brain magnetic resonance imaging. Walking activity was measured by daily step counts (steps∙day⁻¹), recorded using an Actigraph GT3x+ triaxial accelerometer over 7 consecutive days. Voxel-based lesion-symptom mapping was performed to identify brain areas associated with walking activity following stroke.ResultsParticipants presented 4491.9 ± 2473.7 steps∙day⁻¹. Lower levels of walking activity were related to lesions of the posterior part of the putamen, of the posterior limb of the internal capsule and of the anterior part of the corona radiata. No cortical region was associated with walking activity.ConclusionsOur preliminary results identify subcortical neuroanatomical correlates for reduced walking activity following stroke. If confirmed, these results could serve as a rationale for the development of targeted rehabilitative strategy to improve mobility after stroke.     

White-matter microstructure and language lateralization in left-handers: A whole-brain MRI analysis

Most people are left-hemisphere dominant for language. However the neuroanatomy of language lateralization is not fully understood. By combining functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI), we studied whether language lateralization is associated with cerebral white-matter (WM) microstructure. Sixteen healthy, left-handed women aged 20–25 were included in the study. Left-handers were targeted in order to increase the chances of involving subjects with atypical language lateralization. Language lateralization was determined by fMRI using a verbal fluency paradigm. Tract-based spatial statistics analysis of DTI data was applied to test for WM microstructural correlates of language lateralization across the whole brain. Fractional anisotropy and mean diffusivity were used as indicators of WM microstructural organization. Right-hemispheric language dominance was associated with reduced microstructural integrity of the left superior longitudinal fasciculus and left-sided parietal lobe WM. In left-handed women, reduced integrity of the left-sided language related tracts may be closely linked to the development of right hemispheric language dominance. Our results may offer new insights into language lateralization and structure–function relationships in human language system.     

fMRI of developmental stuttering: a pilot study

The purpose of this investigation was to explore the feasibility of fMRI in the study of developmental stuttering. Speech contrasts (loud versus silent reading) and language contrasts (reading of semantically meaningful text versus nonsense words) of six developmental stutterers and six nonstutterers were compared using a commercial 1 Tesla MR-Scanner (Siemens Expert). Results indicate that mapping cortical function in persons who stutter is indeed feasible, even with a 1TMR-system. Compared to normals the stutterers seemed to employ different and particularly less differentiated auditory and motor feedback strategies in speech. They apparently rely on auditory processing and on cerebellar contribution as much during silent reading as during reading aloud. Moreover, they showed a greater involvement of the right hemisphere in language processing, activating not only the typical language areas on the left but also and with equal magnitude the right side homologues of these areas. In spite of the promising results, at present several practical problems such as possible movement artifacts and possible masking through scanner noise still hamper a more straightforward use of fMRI in the study of developmental stuttering.     

Pharmacologic Treatment of Attention-Deficit/Hyperactivity Disorder: Efficacy,Safety and Mechanisms of Action

Studies examining the efficacy, safety and mechanisms of action of agents for the treatment of attention-deficit/hyperactivity disorder (ADHD) are reviewed, with an emphasis on newer agents such as the long acting stimulants and atomoxetine. Recent studies of medications are characterized by large, rigorously diagnosed samples of children, adolescents and adults with ADHD, use of standardized rating scales and extensive safety data. These studies confirm a robust treatment effect for the Food and Drug Administration approved agents ranging from 0.7 to 1.5. The most common short term side effects to the most commonly used agents include insomnia, loss of appetite, and headaches. Despite public controversy and labeling changes to warn of extremely rare cardiovascular and psychiatric side effects, the evidence does not support the hypothesis that medication for ADHD increases risk for sudden death, mania or psychosis. A wide variety of neuroimaging techniques including electrocephalogram (EEG) power, event related potentials (ERP), functional magnetic resonance imaging (fMRI), and positron emission tomography (PET) are beginning to examine the mechanisms of action of medications for ADHD, and implicating the catecholamines and prefrontal and anterior cingulate cortices as prime sites of actions for these agents.     

Measuring activity using actometers: A methodological study

Actometers are men's self-winding mechanical wristwatches that have been modified such that they measure activity rather than time. Actometers can be used to obtain longitudinal naturalistic measures of activity concerning a variety of clinical populations. However, no systematic methodological research has been conducted with regard to the site of attachment and the duration of measurement necessary to ensure valid results. This article presents the results of a methodological study designed to answer these questions. The mean activity levels associated with the Left Wrist and Ankle were nearly equal to those associated with the Right Wrist and Ankle. The Ankle readings were substantially greater than the Wrist readings because the subjects' legs were longer than their arms. The data from Week 2 were the same as those from Week 1.     

The disjunction effect reexamined: Relevant methodological issues and the fallacy of unspecified percentage comparisons

Leonard J. Savage’s sure-thing principle (1954) is a key assumption of the consequentialist conception of decision making under uncertainty, which more-or-less assumes that decision makers are rational and thorough. The sure-thing principle states that if some option x is preferred given some other event A occurs, and if option x is preferred given this event A does not occur, then x should be preferred even when the outcome of A is unknown. Tversky and Shafir [Tversky, A., &; Shafir, E. (1992). The disjunction effect in choice under uncertainty. Psychological Science, 3(5) 305–309] claim that this basic principle is frequently violated in two-step gambles. They call such violations disjunction effects. Kuhberber, Komunska, and Perner [Kuhberber, A., Komunska, D., &; Perner, J. (2001). The disjunction effect: does it exist for two step gambles? Organizational Behavior and Human Decision Processes, 85(2) 250–264] attempted to replicate Tversky and Shafir’s findings and claim their results show that people do not violate the sure-thing principle in repeated gambles. This article evaluates Kuhberger, Komunska, and Perner’s claims, suggesting they did not appropriately analyze their results, and further provides evidence that people do regularly violate the sure-thing principle in two-step gambles, providing further evidence for the reality of disjunction effects.     

The Contribution of Neuroimaging to the Study of Language and Aphasia

New structural and functional imaging methods continue to be developed at a rapid pace. In the last 25 years, advanced imaging techniques have provided insights into how language is represented and processed in the brain and how it can be disrupted by damage to, or dysfunction of, various parts of the brain. Imaging studies have also yielded new information regarding how individuals recover language after stroke. We briefly review the strengths and weaknesses of the various radiological methods currently used to study language and aphasia.     

长期高策略性技能训练对运动员大脑白质结构的影响：一项DTI研究

目前关于运动员经验优势的脑机制还存在争议, 尤其对于涉及较多认知过程参与的高策略性技能项目运动员, 其大脑白质结构可塑性变化还需进一步探究。研究横向对比了乒乓球运动员和非运动员大脑白质纤维束的弥散张量成像数据。结果发现, 相比于非运动员, 乒乓球运动员在连接背侧和腹侧通路脑区的双侧皮质脊髓束、左侧上纵束、左侧下纵束和双侧额枕下束的各向异性值(FA)更大, 进一步分析发现, 部分腹侧通路白质纤维束FA增加的原因是径向扩散系数(RD)下降。研究结果支持了动作双通路模型。提示经过长期高策略性技能训练, 乒乓球运动员在背侧和腹侧通路上的白质纤维束结构完整性增强。     

Leadership and regressive group processes: A pilot study

Various perspectives on leadership within the psychoanalytic, organizational and socio‐biological literature are reviewed, with particular attention to research studies in these areas. Hypotheses are offered about what makes an effective leader: her ability to structure tasks well in order to avoid destructive regressions, to make constructive use of the omnipresent regressive energies in group life, and to redirect regressions when they occur. Systematic qualitative observations of three videotaped sessions each from N = 18 medical staff work groups at an urban medical center are discussed, as is the utility of a scale, the Leadership and Group Regressions Scale (LGRS), that attempts to operationalize the hypotheses. Analyzing the tapes qualitatively, it was noteworthy that at times (in N = 6 groups), the nominal leader of the group did not prove to be the actual, working leader. Quantitatively, a significant correlation was seen between leaders’ LGRS scores and the group’s satisfactory completion of their quantitative goals (p = 0.007) and ability to sustain the goals (p = 0.04), when the score of the person who met criteria for group leadership was used.     

Concreteness training reduces dysphoria: A pilot proof-of-principle study

We hypothesized that a tendency towards abstract, general and decontextualized processing is a cognitive distortion that causally contributes to symptoms of depression. This hypothesis predicts that training dysphoric individuals to become more concrete and specific in their thinking would reduce depressive symptoms. To test this prediction, participants with stable dysphoria (scoring ≥ 14 on BDI-II at 2 consecutive weekly assessments) were randomly allocated in an additive design either to an active intervention control consisting of relaxation training or relaxation training plus concreteness training. Concreteness training involved repeated mental exercises designed to encourage more concrete and specific thinking about emotional events. Both interventions involved a training session and then repeated daily use of compact disc recordings for 7 days. Relaxation training plus concreteness training resulted in significantly greater decreases in depressive symptoms and marginally significantly greater decreases in state rumination than relaxation training alone. These findings suggest the potential value of concreteness training as a guided self-help intervention for mild-to-moderate depressive symptoms.     

Treatment of incest and pedophilic offenders: A pilot study

Twenty-nine incest and 22 heterosexual pedophilic offenders, under sentence, participated in a study of therapeutic outcome. Results showed the two groups were remarkably similar in their pretreatment level of psychosocial functioning. However, pedophiles had a significantly higher recidivism rate than incestuous men. Incest offenders, on the whole, changed most relative to single or married pedophiles. Pedophiles appeared more treatment resistant in dealing with their disturbed family relations, verbal hostility, irritability, and feelings of anger that, in part, underlie their sexual anomaly. At follow-up 36 months later, only 2 incest and 4 pedophilic men had recidivated. The discussion links these findings with earlier research and proposes a multimodal, group-oriented approach to treating sex offenders.     

Effects of motor intention on the perception of somatosensory events: A behavioural and functional magnetic resonance imaging study

The intention to execute a movement can modulate our perception of sensory events, and this modulation is observed ahead of both ocular and upper limb movements. However, theoretical accounts of these effects, and also the empirical data, are often contradictory. Accounts of “active touch”, and the premotor theory of attention, have emphasized how movement intention leads to enhanced perceptual processing at the target of a movement, or on the to-be-moved effector. By contrast, recent theories of motor control emphasize how internal “forward” model (FM) estimates may be used to cancel or attenuate sensory signals that arise as a result of self-generated movements. We used behavioural and functional brain imaging (functional magnetic resonance imaging, fMRI) to investigate how perception of a somatosensory stimulus differed according to whether it was delivered to a hand that was about to execute a reaching movement or the alternative, nonmoving, hand. The results of our study demonstrate that a somatosensory stimulus delivered to a hand that is being prepared for movement is perceived to have occurred later than when that same stimulus is delivered to a nonmoving hand. This result indicates that it takes longer for a tactile stimulus to be detected when it is delivered to a moving limb and may correspond to a change in perceptual threshold. Our behavioural results are paralleled by the results of our fMRI study that demonstrated that there were significantly reduced blood-oxygen-level-dependent (BOLD) responses within the parietal operculum and insula following somatosensory stimulation of the hand being prepared for movement, compared to when an identical stimulus was delivered to a nonmoving hand. These findings are consistent with the prediction of FM accounts of motor control that postulate that central sensory suppression of somatosensation accompanies self-generated limb movements, and with previous reports indicating that effects of sensory suppression are observed in higher order somatosensory regions.     

Enhancing treatment effectiveness through social modelling: A pilot study

Objective: Medical treatments take place in social contexts; however, little research has investigated how social modelling might influence treatment outcomes. This experimental pilot study investigated social modelling of treatment effectiveness and placebo treatment outcomes.

Design: Fifty-nine participants took part in the study, ostensibly examining the use of beta-blockers (actually placebos) for examination anxiety. Participants were randomly assigned to observe a female confederate report positive treatment effects (reduced heart rate, relaxed, calm) or feeling no different.

Main outcome measures: Heart rate, anxiety and blood pressure were assessed, as were symptoms and attributed side effects.

Results: Heart rate decreased significantly more in the social modelling compared to control condition, p = .027 (d = .63), and there were trends towards effects in the same direction for both anxiety, p = .097 (d = .46), and systolic blood pressure, p = .077 (d = .51). Significant pre-post placebo differences in heart rate, anxiety and diastolic blood pressure were found in the social modelling group, ps < .007 (ds = .77–1.37), but not the control condition, ps > .28 (ds = .09–.59).

Conclusions: Social observation of medication effectiveness enhanced placebo effectiveness in heart rate, and showed a trend towards enhancing treatment effectiveness in both anxiety and systolic blood pressure. Social modelling may have utility in enhancing the effectiveness of many active medical treatments.     

Establishing motion control in children with autism and intellectual disability: Applications for anatomical and functional MRI

Excessive motion makes magnetic resonance imaging (MRI) extremely challenging among children with autism spectrum disorder (ASD). The medical risks of sedation establish the need for behavioral interventions to promote motion control among children with ASD undergoing MRI scans. We present a series of experiments aimed at establishing both tolerance of the MRI environment and a level of motion control that would be compatible with a successful MRI. During Study 1, we evaluated the effects of prompting and contingent reinforcement on compliance with a sequence of successive approximations to an MRI using a mock MRI. During Study 2, we used prompting and progressive differential reinforcement of other behaviors (DRO) to promote motion control in a mock MRI for increasing periods of time. Finally, during Study 3, some of the participants underwent a real MRI scan while a detailed in‐session motion analysis informed the quality of the images captured.     

Group-based problem-solving therapy in self-poisoning females: A pilot study

Aims: The treatment of suicidal behaviour remains limited in efficacy. This pilot study assessed the effectiveness of a time-limited, group-based problem-solving therapy intervention compared with a treatment as usual control group, in females who self-poison. Method: A total of 18 clients were equally randomised to treatment or control groups. All clients were assessed using standardised questionnaires for depression, hopelessness, suicidal ideation and social problem-solving skills, at pre-treatment, post-treatment and two months follow-up. Results: The treatment group experienced significant reductions in levels of depression, hopelessness, suicidal ideation and improvements in self-assessed social problem-solving skills. Improvements in mental health and aspects of self-assessed problem-solving skills for the treatment group continued to be evident at two months follow-up. The control group did not change significantly over time on mental health measures or social problem solving abilities. Conclusion: Although limited by small sample size, the results suggest that group-based problem-solving therapy is effective in the management of deliberate self-poisoning. This paper is a unique contribution in that it examines the implementation of problem solving therapy with a homogenous population and in a group format. Methodological concerns and directions for future research are discussed.     

Towards a functional analysis of delinquent behaviour: A pilot study

The events surrounding the delinquent behaviour of 21 juvenile offenders were examined in terms of the antecedents and consequences of these behaviours and with reference to the functional value of the behaviour to the individual. The results are analysed using reversal theory and the importance of the motivational state of the offender at the time the crime is carried out is stressed.