Objective: To investigate structural basal ganglia abnormalities in attention-deficit hyperactivity disorder (ADHD) and their relationship with the neuropsychological deficits and behavioral problems found in ADHD. Design: Case-control study. Setting: Adolescents were recruited from a local polytechnic institute of secondary education. Subjects: Eleven adolescents with ADHD and 19 healthy control subjects. Subjects with ADHD were diagnosed by the school psychologist from a total population of 450 students according to theDiagnostic and Statistical Manual of Mental Disorders, Third Edition, Revised. Diagnosis was confirmed by the Conners Teachers Rating Scale and a structured family interview. Main Outcome Measures: Magnetic resonance imaging single-slice transversal measurements of the head of the caudate nucleus and a comprehensive neuropsychological evaluation, which was specially designed to assess frontal-striatal functioning. Results: The ADHD group had a larger right caudate nucleus area than the control group. In control adolescents, larger caudate nucleus areas were associated with poorer performance on tests of attention and higher ratings on the Conners Teachers Rating Scale. Conclusions: These findings provide further evidence of the involvement of the caudate nucleus in the neuropsychological deficits and behavioral problems found in ADHD. The larger caudate nucleus found in the ADHD group could be related to a failure of the maturational processes that normally result in volume reduction.

Aim: To analyse the influence of apolipoprotein (APOE) ε4 status on the cognitive and behavioural functions usually impaired after moderate and severe traumatic brain injury (TBI). Methods: In all, 77 patients with TBI selected from 140 consecutive admissions were genotyped for APOE. Each patient was subjected to neuropsychological and neurobehavioural assessment at least 6 months after injury. Results: Performance of participants carrying the ε4 allele was notably worse on verbal memory (Auditory Verbal Learning Test), motor speed, fine motor coordination, visual scanning, attention and mental flexibility (Grooved Pegboard, Symbol Digit Modalities Test and part B of the Trail Making Test) and showed considerably more neurobehavioural disturbances (Neurobehavioral Rating Scale—Revised) than the group without the ε4 allele. Conclusions: In particular, performance on neuropsychological tasks that are presumed to be related to temporal lobe, frontal lobe and white matter integrity is worse in patients with the APOE ε4 allele than in those without it. More neurobehavioural disturbances are observed in APOE ε4 carriers than in APOE ε2 and ε3 carriers.

Resting‐state studies conducted with stroke patients are scarce. The study of brain activity and connectivity at rest provides a unique opportunity for the investigation of brain rewiring after stroke and plasticity changes. This study sought to identify dynamic changes in the functional organization of the default mode network (DMN) of stroke patients at three months after stroke. Eleven patients (eight male and three female; age range: 48–72) with right cortical and subcortical ischemic infarctions and 17 controls (eleven males and six females; age range: 57–69) were assessed by neurological and neuropsychological examinations and scanned with resting‐state functional magnetic ressonance imaging. First, we explored group differences in functional activity within the DMN by means of probabilistic independent component analysis followed by a dual regression approach. Second, we estimated functional connectivity between 11 DMN nodes both locally by means of seed‐based connectivity analysis, as well as globally by means of graph‐computation analysis. We found that patients had greater DMN activity in the left precuneus and the left anterior cingulate gyrus when compared with healthy controls (P < 0.05 family‐wise error corrected). Seed‐based connectivity analysis showed that stroke patients had significant impairment (P = 0.014; threshold = 2.00) in the connectivity between the following five DMN nodes: left superior frontal gyrus (lSFG) and posterior cingulate cortex (t = 2.01); left parahippocampal gyrus and right superior frontal gyrus (t = 2.11); left parahippocampal gyrus and lSFG (t = 2.39); right parietal and lSFG (t = 2.29). Finally, mean path length obtained from graph‐computation analysis showed positive correlations with semantic fluency test (r _s = 0.454; P = 0.023), phonetic fluency test (r _s = 0.523; P = 0.007) and the mini mental state examination (r _s = 0.528; P = 0.007). In conclusion, the ability to regulate activity of the DMN appears to be a central part of normal brain function in stroke patients. Our study expands the understanding of the changes occurring in the brain after stroke providing a new avenue for investigating lesion‐induced network plasticity. Hum Brain Mapp 36:577–590, 2015. © 2014 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.

The primary goal of this study was to determine the incidence of post-traumatic ventriculomegaly (Evans' index ≥ 0.30) in 95 head-injured patients with a Glasgow Coma Scale (GCS) score of ≤13 at admission. Additional objectives were to determine the relationship between an increase in ventricular size and several clinical and radiological features and outcome. A planimetric study was carried out in the sequential control computed tomography (CT) scans of 34 moderately head-injured (GCS 9–13) and 61 severely head-injured (GCS 3–8) patients with a minimum follow-up of 2 months. Between two and six CT scans were evaluated in each patient. The presence of subarachnoid hemorrhage (SAH) was registered. Evans' index was determined in all CT scans. In the final CT scan of each patient, ventricular size was related to the admission GCS score, age, the presence of SAH in the initial CT scans, type of brain lesion (classified according to the final diagnosis in the Traumatic Coma Data Bank classification), and outcome. Ventriculomegaly was found in 39.3% of patients with severe head injury and in 27.3% of those with a moderate head injury. Increased ventricular size was evident 4 weeks after injury in 57.6% and 2 months after injury in 69.7%. No relationship was found between post-traumatic ventriculomegaly and age, initial GCS score, the presence of SAH, or type of lesion (focal or diffuse). Post-traumatic ventriculomegaly was significantly correlated with outcome. Post-traumatic ventriculomegaly is a frequent and early finding in patients with moderate or severe traumatic brain injury.

Resting‐state studies conducted with stroke patients are scarce. First objective was to explore whether patients with good cognitive recovery showed differences in resting‐state functional patterns of brain activity when compared to patients with poor cognitive recovery. Second objective was to determine whether such patterns were correlated with cognitive performance. Third objective was to assess the existence of prognostic factors for cognitive recovery. Eighteen right‐handed stroke patients and eighteen healthy controls were included in the study. Stroke patients were divided into two groups according to their cognitive improvement observed at three months after stroke. Probabilistic independent component analysis was used to identify resting‐state brain activity patterns. The analysis identified six networks: frontal, fronto‐temporal, default mode network, secondary visual, parietal, and basal ganglia. Stroke patients showed significant decrease in brain activity in parietal and basal ganglia networks and a widespread increase in brain activity in the remaining ones when compared with healthy controls. When analyzed separately, patients with poor cognitive recovery (n = 10) showed the same pattern as the whole stroke patient group, while patients with good cognitive recovery (n = 8) showed increased activity only in the default mode network and fronto‐temporal network, and decreased activity in the basal ganglia. We observe negative correlations between basal ganglia network activity and performance in Semantic Fluency test and Part A of the Trail Making Test for patients with poor cognitive recovery. A reverse pattern was observed between frontal network activity and the abovementioned tests for the same group. Hum Brain Mapp 35:3819–3831, 2014. © 2014 The Authors. Human Brain Mapping published by Wiley Periodicals, Inc.