Does frontal brain activity mediate the effect of depression prevention in adolescents? A pilot study.

We investigated whether (a) depression prevention was associated with depressive symptoms and medial-frontal alpha asymmetry in adolescents; (b) alpha asymmetry mediated the association between participation in a prevention program and depressive symptoms; and (c) gender affects these associations. In our randomised control group study, we compared a universal prevention program (n = 40 adolescents, 14 females) with a non-intervention control condition (n = 39 adolescents, 20 females) in German secondary school students (mean age: 13.53 years, SD = 0.53). We collected data at baseline, post-intervention, 6-month, and 12-month follow-up using the Self-Rating Questionnaire for Depressive Disorders (SBB-DES) and resting medial-frontal alpha activity on F3 and F4. We found that girls benefitted from participating in the prevention program in regards to their depressive symptoms at 12-month follow-up but not alpha asymmetry. In boys, participation in the prevention program was associated with their alpha asymmetry at 6-month follow-up but not their depressive symptoms. Alpha asymmetry did not mediate the effects of the prevention program on depressive symptoms in either gender. Although participation in the prevention program was associated with both depressive symptoms and alpha asymmetry, those associations seem independent from each other. Possible explanations for this result pattern are discussed.

Variation in early life maternal care predicts later long range frontal cortex synapse development in mice.

Empirical and theoretical work suggests that early postnatal experience may inform later developing synaptic connectivity to adapt the brain to its environment. We hypothesized that early maternal experience may program the development of synaptic density on long range frontal cortex projections. To test this idea, we used maternal separation (MS) to generate environmental variability and examined how MS affected 1) maternal care and 2) synapse density on virally-labeled long range axons of offspring reared in MS or control conditions. We found that MS and variation in maternal care predicted bouton density on dorsal frontal cortex axons that terminated in the basolateral amygdala (BLA) and dorsomedial striatum (DMS) with more, fragmented care associated with higher density. The effects of maternal care on these distinct axonal projections of the frontal cortex were manifest at different ages. Maternal care measures were correlated with frontal cortex → BLA bouton density at mid-adolescence postnatal (P) day 35 and frontal cortex → DMS bouton density in adulthood (P85). Meanwhile, we found no evidence that MS or maternal care affected bouton density on ascending orbitofrontal cortex (OFC) or BLA axons that terminated in the dorsal frontal cortices. Our data show that variation in early experience can alter development in a circuit-specific and age-dependent manner that may be relevant to understanding the effects of early life adversity.

Supratentorial neuroenteric cyst in children: a case report and brief literature review.

Neurenteric cysts are rare developmental lesions typically found outside the central nervous system but when they do, we most likely find them in a spinal (cervical or dorsal) intradural extramedular location, often associated with dysraphism. The more unusual intracranial cases have been published because of its rarity, occurring mostly as a posterior fossa extra-axial cyst, in adults. Supratentorial cases are distinctly infrequent, especially in children, resulting in few case reports and even fewer case reviews. We describe a case of a child with a supratentorial neurenteric cyst and present a brief review of the literature about these cysts in children, a noticeable gap in the literature.

Early bilateral and massive compromise of the frontal lobes.

The frontal lobes are one of the most complex brain structures involved in both domain-general and specific functions. The goal of this work was to assess the anatomical and cognitive affectations from a unique case with massive bilateral frontal affectation. We report the case of GC, an eight-year old child with nearly complete affectation of bilateral frontal structures and spared temporal, parietal, occipital, and cerebellar regions. We performed behavioral, neuropsychological, and imaging (MRI, DTI, fMRI) evaluations. Neurological and neuropsychological examinations revealed a mixed pattern of affected (executive control/abstraction capacity) and considerably preserved (consciousness, language, memory, spatial orientation, and socio-emotional) functions. Both structural (DTI) and functional (fMRI) connectivity evidenced abnormal anterior connections of the amygdala and parietal networks. In addition, brain structural connectivity analysis revealed almost complete loss of frontal connections, with atypical temporo-posterior pathways. Similarly, functional connectivity showed an aberrant frontoparietal network and relative preservation of the posterior part of the default mode network and the visual network. We discuss this multilevel pattern of behavioral, structural, and functional connectivity results. With its unique pattern of compromised and preserved structures and functions, this exceptional case offers new constraints and challenges for neurocognitive theories.

Cortical Abnormalities Associated With Pediatric and Adult Obsessive-Compulsive Disorder: Findings From the ENIGMA Obsessive-Compulsive Disorder Working Group.

OBJECTIVE: Brain imaging studies of structural abnormalities in OCD have yielded inconsistent results, partly because of limited statistical power, clinical heterogeneity, and methodological differences. The authors conducted meta- and mega-analyses comprising the largest study of cortical morphometry in OCD ever undertaken. METHOD: T1-weighted MRI scans of 1,905 OCD patients and 1,760 healthy controls from 27 sites worldwide were processed locally using FreeSurfer to assess cortical thickness and surface area. Effect sizes for differences between patients and controls, and associations with clinical characteristics, were calculated using linear regression models controlling for age, sex, site, and intracranial volume. RESULTS: In adult OCD patients versus controls, we found a significantly lower surface area for the transverse temporal cortex and a thinner inferior parietal cortex. Medicated adult OCD patients also showed thinner cortices throughout the brain. In pediatric OCD patients compared with controls, we found significantly thinner inferior and superior parietal cortices, but none of the regions analyzed showed significant differences in surface area. However, medicated pediatric OCD patients had lower surface area in frontal regions. Cohen's d effect sizes varied from -0.10 to -0.33. CONCLUSIONS: The parietal cortex was consistently implicated in both adults and children with OCD. More widespread cortical thickness abnormalities were found in medicated adult OCD patients, and more pronounced surface area deficits (mainly in frontal regions) were found in medicated pediatric OCD patients. These cortical measures represent distinct morphological features and may be differentially affected during different stages of development and illness, and possibly moderated by disease profile and medication.

A Postmortem Study of Frontal and Temporal Gyri Thickness and Cell Number in Human Obesity.

OBJECTIVE: This study aimed to compare cortex thickness and neuronal cell density in postmortem brain tissue from people with overweight or obesity and normal weight. METHODS: The cortex thickness and neuron density of eight donors with overweight or obesity (mean = 31.6 kg/m2 ; SD = 4.35; n = 8; 6 male) and eight donors with normal weight (mean = 21.8 kg/m2 ; SD = 1.5; n = 8; 5 male) were compared. All participants were Mexican and lived in Mexico City. Randomly selected thickness measures of different cortex areas from the frontal and temporal lobes were analyzed based on high-resolution real-size photographs. A histological analysis of systematic-random fields was used to quantify the number of neurons in postmortem left and right of the first, second, and third gyri of frontal and temporal lobe brain samples. RESULTS: No statistical difference was found in cortical thickness between donors with overweight or obesity and individuals with normal weight. A smaller number of neurons was found among the donors with overweight or obesity than the donors with normal weight at different frontal and temporal areas. CONCLUSIONS: A lower density of neurons is associated with overweight or obesity. The morphological basis for structural brain changes in obesity requires further investigation.

Characteristics of EEG Seizure-Onset Patterns Recorded From Subdural Electrodes Over MRI-Visible Frontal Focal Cortical Dysplasia Type IIb Lesions.

PURPOSE: Focal cortical dysplasia (FCD) is intrinsically epileptogenic, and an MRI-visible lesion typically constitutes the core part of the epileptogenic zone. We aimed to identify ictal EEG patterns that represent the epileptogenic zone by using subdural electrodes placed over the MRI-visible FCD lesion. METHODS: We selected seven patients with frontal lobe epilepsy caused by pathologically proven FCD type IIb who underwent preoperative intracranial EEG evaluation with subdural electrodes followed by resection surgery with seizure-free outcome. The characteristics of ictal EEG patterns, interictal/ictal high-frequency oscillations, and ictal direct current shifts from intracranial electrodes placed over the MRI-visible lesion were analyzed. RESULTS: Two seizure-onset patterns (low voltage fast activity and fast spike activity) were identified. Low voltage fast activity was seen in all patients with a lateral frontal lesion, and it was always preceded by preictal spikes. Fast spike activity occurred only in patients with a mesial frontal lesion. Interictal/ictal high-frequency oscillations and ictal direct current shifts were seen in all patients. CONCLUSIONS: The epileptogenic zone of frontal FCD type IIb may be characterized by EEG seizure-onset patterns consisting of low voltage fast activity and fast spike activity accompanied by ictal high-frequency oscillations and ictal direct current shifts. Further study is needed to determine whether other seizure-onset patterns exist in patients with FCD type IIb.

Herniated gyrus rectus causing idiopathic compression of the optic chiasm.

Anomalies in the frontal lobe can interfere with visual function by compression of the optic chiasm and nerve. The gyrus rectus is located at the anterior cranial fossa floor superior to the intracranial optic nerves and chiasm. Compression of these structures by the gyrus rectus is often caused by neoplastic or dysplastic growth in the area. We report a rare case of a herniated gyrus rectus impinged on the optic chiasm and nerve without a clear pathological cause for the herniation.

[INDIVIDUAL EVALUATION OF LORETA ABNORMALITIES IN IDIOPATHIC GENERALIZED EPILEPSY]. / EGYEDI LORETA-ABNORMALITÁSOK VIZSGÁLATA IDIOPATHIÁS GENERALIZÁLT EPILEPSZIÁKBAN.

BACKGROUND: Contemporary neuroimaging methods disclosed structural and functional cerebral abnormalities in idiopathic generalized epilepsies (IGEs). However, individual electrical (EEG) abnormalities have not been evaluated yet in IGE patients. METHODS: IGE patients were investigated in the drug-free condition and after 3-6 month of antiepileptic treatment. To estimate the reproducibility of qEEG variables a retrospective recruited cohort of IGE patients was investigated. 19-channel resting state EEG activity was recorded. For each patient a total of 2 minutes EEG activity was analyzed by LORETA (Low Resolution Electromagnetic Tomography). Raw LORETA values were Z-transformed and projected to a MRI template. Z-values outside within the [+3Z] to [-3Z] range were labelled as statistically abnormal. RESULTS: 1. In drug-free condition, 41-50% of IGE patients showed abnormal LORETA values. 2. Abnormal LORETA findings showed great inter-individual variability. 3. Most abnormal LORETA-findings were symmetrical. 4. Most maximum Z-values were localized to frontal or temporal cortex. 5. Succesfull treatment was mostly coupled with disappearence of LORETA-abnormality, persistent seizures were accompanied by persistent LORETA abnormality. DISCUSSION: 1. LORETA abnormalities detected in the untreated condition reflect seizure-generating property of the cortex in IGE patients. 2. Maximum LORETA-Z abnormalities were topographically congruent with structural abnormalities reported by other research groups. 3. LORETA might help to investigate drug effects at the whole-brain level.

[Tourette syndrome and reading disorder in a boy with left parietofrontal tract disruption]. / Trastorno de Tourette y de la lectura en un niño con disrupción del tracto parietofrontal izquierdo.

We present the case of a nine-year-old boy with Tourette syndrome and reading disorder with a history of a severe infectious process in the late neonatal period. Brain MRI showed a left parietal malacotic cavity and diffusion tensor imaging and tractography showed a striking disruption of the white matter bundle that joins the left parietal region with the ipsilateral frontal region with involvement of the left superior longitudinal fasciculus and of the left arcuate fasciculus. Although Tourette syndrome and reading disorder are fundamentally hereditary neuropsychiatric disorders, they can also occur secondary to cerebral alterations like those existing in this boy. The introduction of modern neuroimaging techniques in patients with neuropsychiatric disorders (or the risk of developing them) can be very useful in the diagnosis and prognosis in the future.

Cortical folding is altered before surgery in infants with congenital heart disease.

Infants with congenital heart disease have altered brain development. We characterized cortical folding, a critical part of brain development, in congenital heart disease infants and demonstrated an overall decrease in cortical surface area and cortical folding with regional alterations in the right lateral sulcus and left orbitofrontal region, cingulate region, and central sulcus. These abnormalities were present prior to surgery.

Early onset and rapid progression of glaucoma in a neonate with Sturge-Weber syndrome.

Sturge-Weber syndrome (SWS) is an uncommon neurocutaneous syndrome usually presenting with a triad of cutaneous, neurological, and ophthalmological symptoms. The cutaneous lesion can be observed at birth in most cases while the symptoms of the nervous and ocular systems involvement usually appear later in life. The most common ocular manifestation in SWS is glaucoma, which can occur in the early-life period. The authors reported a case of SWS in which the symptoms of glaucoma rapidly developed within two weeks following an ophthalmologic evaluation that was initially negative at the age of one week.

Mini supraorbital approach to inferior frontal lobe cavernous malformations: case series.

BACKGROUND: Anterior surgical approaches to the inferior frontal lobe require large craniotomies with long incisions and some risk of cosmetic defects and surgical morbidity. A mini supraorbital keyhole approach is an alternative to these larger craniotomies. Inferior frontal lobe cavernous malformations are an excellent target for this minimally invasive approach, and we present our experience with two patients. METHODS: Two patients with inferior frontal lobe cavernous malformations underwent elective resection of their cavernous malformations through a mini supraorbital craniotomy. The subfrontal exposure opened widely after draining cerebrospinal fluid (CSF) from the carotid cistern to relax the brain. Hemosiderin staining helped identify the underlying cavernous malformations. RESULTS: Both lesions were completely resected. No intraoperative complications, CSF leaks, or neurological deficits were observed. CONCLUSION: The mini supraorbital keyhole craniotomy with microsurgical technique and neuronavigation is an effective approach for treating cavernous malformations in the inferior frontal lobe. This minimally invasive approach reduces incision size, craniotomy size, and associated complications while enhancing cosmetic outcomes.

Frontal brain expansion during development using MRI and endocasts: relation to microcephaly and Homo floresiensis.

A major hall of hominid brain evolution is an expansion of the frontal lobes. To determine if a similar trajectory occurs during modern human development, the MRI scans of 118 living infants, children, and adolescents were reviewed and three specific measurements obtained: frontal width (FW), maximal cerebral width (MW), and maximal cerebral length (ML). The infantile brain is uniformly wide but relatively short, with near equal FW and MW. The juvenile brain exhibits a wider MW than FW, while FW of the adolescent brain expands to nearly equal MW, concurrent with an increase in ML. The preferential frontal lobe expansion during modern human development parallels that observed during the evolution of Homo. In 17 microcephalic individuals, only 6 (35%) exhibited preferential frontal lobe hypoplasia, presumably a reflection of multiple etiologies that adversely affect differing brain regions. Compared to 79 modern human adult endocasts and 12 modern microcephalic endocasts, LB1 (Homo floresiensis) clustered more consistently with the microcephalic sample than with the normocephalic sample.

Reduced limbic metabolism and fronto-cortical volume in rats vulnerable to alcohol addiction.

Alcohol abuse is associated with long-term reductions in fronto-cortical volume and limbic metabolism. However, an unanswered question in alcohol research is whether these alterations are the sole consequence of chronic alcohol use, or contain heritable contributions reflecting biological propensity toward ethanol addiction. Animal models of genetic predisposition to alcohol dependence can be used to investigate the role of inborn brain abnormalities in the aetiology of alcoholism. Here we used magnetic resonance imaging (MRI) in the Marchigian-Sardinian (msP) alcohol-preferring rats to assess the presence of inherited structural or functional brain alterations. Alcohol-naïve msP (N=22) and control rats (N=26) were subjected to basal cerebral blood volume (bCBV) mapping followed by voxel-based morphometry (VBM) of grey matter and tract-based spatial statistics mapping of white matter fractional anisotropy. msP rats exhibited significantly reduced bCBV, an established marker of resting brain function, in focal cortico-limbic and thalamic areas, together with reduced grey matter volume in the thalamus, ventral tegmental area, insular and cingulate cortex. No statistically significant differences in fractional anisotropy were observed between groups. These findings highlight the presence of inborn grey matter and metabolic abnormalities in alcohol-naïve msP rats, the localization and sign of which are remarkably similar to those mapped in abstinent alcoholics and subjects at high risk for alcohol dependence. Collectively, these results point for a significant role of heritable neurofunctional brain alterations in biological propensity toward ethanol addiction, and support the translational use of advanced imaging methods to describe the circuital determinants of vulnerability to drug addiction.