Recurrent hepatocellular carcinoma and non-classic adreno-genital syndrome.

OBJECTIVE: Hepatocellular carcinoma (HCC) is one of the most common fatal cancer in the world and androgens are among the possible etiological factors. Congenital adrenal hyperplasia (CAH) is a group of inherited diseases caused by enzyme failure in the steroid biosynthesis of the adrenal cortex, resulting in an augmented 17-hydroxyprogesterone, androstenedione and testosterone production. While the occurrence of testicular adrenal rest tumors and adrenocortical tumors in congenital adrenal hyperplasia is well described in the literature, no data on HCC occurrence are available. CASE PRESENTATION: A 35-years-old Italian man of Caucasian origin, affected by non-classic CAH due to partial 21-hydroxylase deficiency came to observation for revaluation of his adrenal picture. Besides common hormonal and biochemical analysis, an abdomen Magnetic Resonance Imaging was performed, resulting in an 18 mm large nodular lesion between liver segments VII and VIII. Radiological reports matched with an increased serum α-fetoprotein level. A surgical removal of the lesion was performed. After that, several recurrences of the lesion, which was consequently treated by radiofrequency ablation, occurred. Every recurrence was accompanied by an increase in testosterone and steroid hormone binding globulin serum levels. CONCLUSIONS: Our report suggests the need for screening of liver lesions in males affected by this syndrome.

Early diagnosis of Alzheimer's disease: the role of biomarkers including advanced EEG signal analysis. Report from the IFCN-sponsored panel of experts.

Alzheimer's disease (AD) is the most common neurodegenerative disease among the elderly with a progressive decline in cognitive function significantly affecting quality of life. Both the prevalence and emotional and financial burdens of AD on patients, their families, and society are predicted to grow significantly in the near future, due to a prolongation of the lifespan. Several lines of evidence suggest that modifications of risk-enhancing life styles and initiation of pharmacological and non-pharmacological treatments in the early stage of disease, although not able to modify its course, helps to maintain personal autonomy in daily activities and significantly reduces the total costs of disease management. Moreover, many clinical trials with potentially disease-modifying drugs are devoted to prodromal stages of AD. Thus, the identification of markers of conversion from prodromal form to clinically AD may be crucial for developing strategies of early interventions. The current available markers, including volumetric magnetic resonance imaging (MRI), positron emission tomography (PET), and cerebral spinal fluid (CSF) analysis are expensive, poorly available in community health facilities, and relatively invasive. Taking into account its low cost, widespread availability and non-invasiveness, electroencephalography (EEG) would represent a candidate for tracking the prodromal phases of cognitive decline in routine clinical settings eventually in combination with other markers. In this scenario, the present paper provides an overview of epidemiology, genetic risk factors, neuropsychological, fluid and neuroimaging biomarkers in AD and describes the potential role of EEG in AD investigation, trying in particular to point out whether advanced analysis of EEG rhythms exploring brain function has sufficient specificity/sensitivity/accuracy for the early diagnosis of AD.

Critical analysis of major and ancillary features of LI-RADS v2018 in the differentiation of small (≤ 2 cm) hepatocellular carcinoma from dysplastic nodules with gadobenate dimeglumine-enhanced magnetic resonance imaging.

OBJECTIVE: To evaluate the performance of major features, ancillary features, and categories of Liver Imaging Reporting and Data System (LI-RADS) version 2018 at magnetic resonance (MR) imaging in the differentiation of small hepatocellular carcinoma (HCC) from dysplastic nodules (DNs). PATIENTS AND METHODS: This retrospective study included cirrhotic patients with pathologically proven untreated HCCs and DNs (≤ 2 cm) and liver MR imaging performed with gadobenate dimeglumine contrast agent within 3 months before pathological analysis, between 2015 and 2018. 37 patients with 43 observations (17 HCCs and 26 DNs) met the inclusion criteria. Two radiologists assessed major and ancillary imaging features for each liver observation and assigned a LI-RADS v2018 category in consensus. Estimates of diagnostic performance of major features, ancillary features, and LI-RADS categories were assessed based on their sensitivity, specificity, positive (PPV), and negative predictive values (NPV). RESULTS: Major features (nonrim arterial phase hyperenhancement, nonperipheral "washout", and enhancing "capsule") had a sensitivity of 94.1%, 88.2%, and 41.2%, and a specificity of 57.7%, 42.3%, and 88.5% for HCC, respectively. Ancillary features (hepatobiliary phase hypointensity, mild-moderate T2 hyperintensity, restricted diffusion, and fat in the lesion more than adjacent liver) had a sensitivity of 94.1%, 64.7%, 58.8%, and 11.8%, and a specificity of 26.9%, 61.5%, 65.4%, and 76.9% for HCC, respectively. The LR-5 category (determined by using major features only vs. the combination of major and ancillary features) had a sensitivity of 88.2% at both evaluations and a specificity of 76.9% and 80.8% for HCC, respectively. The combination of LR-4, LR-5 categories (determined by using major features only vs. the combination of major and ancillary features) had a sensitivity of 94.1% at both interpretations and a specificity of 65.4% and 26.9% for HCC, respectively. The use of ancillary features modified LI-RADS category in 25.6% of observations (11/43), predominantly upgraded from LR-3 to LR4 (10/11), increasing the proportion of low-grade DNs and high-grade DNs categorized as LR-4 (from 15.4% to 61.5% and from 7.7% to 46.1%, respectively). CONCLUSIONS: The added value of ancillary features in combination with major features is limited for the non-invasive diagnosis of small HCC; however, their use modifies the final category in a substantial proportion of observations from LR-3 to LR-4, thus allowing possible changes in the management of patients at risk for HCC.

Low molecular weight heparin as cause of liver injury: case report and literature review.

Low molecular weight heparins (LMWH) are a class of drugs including various molecules that inhibit predominantly the factor V of coagulation and are used in a wide range of clinical settings for the management of venous thromboembolism and acute coronary syndrome. Despite LMWH are considered safe and associated with a lower incidence of side effects compared to unfractioned heparin, it is worth considering that the use of LWMH can be associated with complications. Some of these, such as bleeding and thrombocytopenia, are well-known, whereas other ones are often underestimated leading to a diagnostic delay. In this case report, we describe a case of a 73-years-old man who recently started nadroparin for deep vein thrombosis presenting with acute hepatitis. The diagnostic workup of drug-induced liver injury (DILI) requires the exclusion of other causative agents and temporal association between the initiation of the culprit drug and hyper aminotransferasemia. This clinical case analyzes how to deal with a suspicion of DILI and consider LWMH as a potential cause of DILI, which requires a modification of the anticoagulant treatment.

Methods for analysis of brain connectivity: An IFCN-sponsored review.

The goal of this paper is to examine existing methods to study the "Human Brain Connectome" with a specific focus on the neurophysiological ones. In recent years, a new approach has been developed to evaluate the anatomical and functional organization of the human brain: the aim of this promising multimodality effort is to identify and classify neuronal networks with a number of neurobiologically meaningful and easily computable measures to create its connectome. By defining anatomical and functional connections of brain regions on the same map through an integrated approach, comprising both modern neurophysiological and neuroimaging (i.e. flow/metabolic) brain-mapping techniques, network analysis becomes a powerful tool for exploring structural-functional connectivity mechanisms and for revealing etiological relationships that link connectivity abnormalities to neuropsychiatric disorders. Following a recent IFCN-endorsed meeting, a panel of international experts was selected to produce this current state-of-art document, which covers the available knowledge on anatomical and functional connectivity, including the most commonly used structural and functional MRI, EEG, MEG and non-invasive brain stimulation techniques and measures of local and global brain connectivity.

Cortical connectivity and memory performance in cognitive decline: A study via graph theory from EEG data.

Functional brain abnormalities including memory loss are found to be associated with pathological changes in connectivity and network neural structures. Alzheimer's disease (AD) interferes with memory formation from the molecular level, to synaptic functions and neural networks organization. Here, we determined whether brain connectivity of resting-state networks correlate with memory in patients affected by AD and in subjects with mild cognitive impairment (MCI). One hundred and forty-four subjects were recruited: 70 AD (MMSE Mini Mental State Evaluation 21.4), 50 MCI (MMSE 25.2) and 24 healthy subjects (MMSE 29.8). Undirected and weighted cortical brain network was built to evaluate graph core measures to obtain Small World parameters. eLORETA lagged linear connectivity as extracted by electroencephalogram (EEG) signals was used to weight the network. A high statistical correlation between Small World and memory performance was found. Namely, higher Small World characteristic in EEG gamma frequency band during the resting state, better performance in short-term memory as evaluated by the digit span tests. Such Small World pattern might represent a biomarker of working memory impairment in older people both in physiological and pathological conditions.

Small-worldness characteristics and its gender relation in specific hemispheric networks.

Aim of this study was to verify whether the topological organization of human brain functional networks is different for males and females in resting state EEGs. Undirected and weighted brain networks were computed by eLORETA lagged linear connectivity in 130 subjects (59 males and 71 females) within each hemisphere and in four resting state networks (Attentional Network (AN), Frontal Network (FN), Sensorimotor Network (SN), Default Mode Network (DMN)). We found that small-world (SW) architecture in the left hemisphere Frontal network presented differences in both delta and alpha band, in particular lower values in delta and higher in alpha 2 in males respect to females while in the right hemisphere differences were found in lower values of SW in males respect to females in gamma Attentional, delta Sensorimotor and delta and gamma DMNs. Gender small-worldness differences in some of resting state networks indicated that there are specific brain differences in the EEG rhythms when the brain is in the resting-state condition. These specific regions could be considered related to the functions of behavior and cognition and should be taken into account both for research on healthy and brain diseased subjects.

Enhancement patterns of intrahepatic mass-forming cholangiocarcinoma at multiphasic computed tomography and magnetic resonance imaging and correlation with clinicopathologic features.

OBJECTIVE: Incidence of intrahepatic mass-forming cholangiocarcinoma (IMCC) is increasing worldwide, especially in patients with chronic liver disease. The small and the histologically well-differentiated IMCCs in chronic liver disease could be arterially hypervascular lesions with/without washout on computed tomography (CT) and magnetic resonance imaging (MRI), mimicking typical hepatocellular carcinoma (HCC). The aim of this work is to evaluate contrast enhancement (CE) patterns of IMCCs at quadri-phasic multidetector CT (4-MDCT) and MRI, using imaging-clinicopathologic correlation. PATIENTS AND METHODS: The 4-MDCT and MR images of 56 histologically confirmed IMCCs were retrospectively evaluated for tumor morphology and enhancement features. Enhancement pattern was defined according to the behavior of the nodule in arterial (AP), portal venous (PVP) and equilibrium phases (EP), and dynamic pattern was described according to enhancement progression throughout the different phases. Arterial and dynamic enhancement patterns were correlated with chronic liver disease, tumor size and histological differentiation. RESULTS: Most of the nodules were peripherally hyperenhancing (50%) on AP, and partially hyperenhancing on PVP (67.9%) and EP (80.3%). Forty-six (82.1%) IMCCs showed progressive CE, 7 (12.5%) stable CE and 3 (5.4%) wash-out. In normal liver there were 34 nodules with progressive and 3 with stable CE, whereas in chronic liver disease there were 12 IMCCs with progressive, 4 with stable and 3 with washout pattern (p = 0.01); IMCCs with progressive CE were more differentiated than IMCCs with stable CE and wash-out (p = 0.02). CONCLUSIONS: The most prevalent enhancement pattern of IMCCs was arterial rim enhancement followed by progressive and concentric filling. The stable and the washout patterns were more frequent in poorly differentiated IMCCs. Contrast washout was observed only in IMCCs emerging in chronic liver disease with a risk of misdiagnosis with HCC.

Can HLA-DRB4 Help to Identify Asthmatic Patients at Risk of Churg-Strauss Syndrome?

HLA-DRB4 gene is associated with Churg-Strauss syndrome (CSS), a systemic eosinophilic vasculitis with a prodromal phase characterized by severe asthma, eosinophilia, nasal polyposis, and sinusitis. Aim of this study was to evaluate if the presence of HLA-DRB4 in asthmatic patients is associated with a clinical picture resembling that of the prodromal phase of CSS. HLA-DRB1 was determined in a cohort of 159 asthmatic patients and its frequency was compared with that of 1808 blood donors. HLA-DRB4 presence/absence was correlated with clinical features, including sinusitis, nasal polyposis, eosinophils, antiasthmatic drugs, asthma severity, and pulmonary function tests. HLA-DRB4 gene was associated with severe persistent asthma before treatment (P < 0.02), near fatal or severe hypoxemic asthma (P < 0.01), sinusitis (P < 0.01), nasal polyposis (P < 0.01), number of patients with eosinophils >1000/ µ l: (P < 0.05), need of beclomethasone >1000-2000 µ g/daily (P < 0.001), use of a third controller (P < 0.05), and oral prednisone (P < 0.02). HLA-DRB4 gene is associated in asthmatic patients with a clinical picture characterized by asthma severity, sinusitis, nasal polyposis, and eosinophilia closely resembling that of the prodromal phase of CSS and might be useful to suspect corticosteroids-masked cases of CSS.

The choice of whether to participate in a phase I clinical trial: increasing the awareness of patients with cancer. An exploratory study.

OBJECTIVE: In a previous study, we found that patients who were offered the possibility of participation in a clinical trial had unexpressed concerns and fears that prevented them from making free or fully knowledgeable choices about their trial participation. In a selected population of patients who were offered participation in a phase I trial, we prospectively investigated whether a face-to-face discussion about their unexpressed fears might lead to a more conscious decision about whether to accept/refuse participation in the trial. METHODS: After the presentation of the trial, a questionnaire was administered to assess the presence of specific fears. Before the patients decided whether to participate in the trial, they discussed any fears that they had; finally, the impact of the discussion on the patients' choice to participate was evaluated. RESULTS: The majority (86%) of the patients thought that physicians conduct clinical trials for scientific interest, 13% felt exploited as 'guinea pigs' and 20% believed they were offered participation because they had no further hope for improvement. These existing fears were not elicited during the trial interview because the patients were themselves unaware of having them (28%) and because of fear of the doctors (3%). The possibility of discussing these fears was felt as an opportunity and made patients feel more conscious (92%) and freer (97%) when making their choice. CONCLUSIONS: Recognising and discussing misconceptions and fears, often unexpressed, make patients freer and more aware when facing the choice of whether or not \to participate in a phase I clinical trial.

Sleep and bodily functions: the physiological interplay between body homeostasis and sleep homeostasis.

Body homeostasis and sleep homeostasis may both rely on the complex integrative activity carried out by the hypothalamus. Thus, the three main wake-sleep (WS) states (i.e. wakefulness, NREM sleep, and REM sleep) may be better understood if the different cardio-respiratory and metabolic parameters, which are under the integrated control of the autonomic and the endocrine systems, are studied during sleep monitoring. According to this view, many physiological events can be considered as an expression of the activity that physiological regulations should perform in order to cope with the need to fulfill body and sleep homeostasis. This review is aimed at making an assessment of data showing the existence of a physiological interplay between body homeostasis and sleep homeostasis, starting from the spontaneous changes observed in the somatic and autonomic activity during sleep, through evidence showing the deep changes occurring in the central integration of bodily functions during the different WS states, to the changes in the WS states observed when body homeostasis is challenged by the external environment and when the return to normal ambient conditions allows sleep homeo- stasis to run without apparent physiological restrictions. The data summarized in this review suggest that an approach to the dichotomy between NREM and REM sleep based on physiological regulations may offer a framework within which observations that a traditional behavioral approach may overlook can be interpreted. The study of the interplay between body and sleep homeostasis appears, therefore, to be a way to understand the function of complex organisms beyond that of the specific regulations.

Prognostic implications of the lymph node count after neoadjuvant treatment for rectal cancer.

BACKGROUND: The aim of this study was to investigate the effect of neoadjuvant chemoradiotherapy on the lymph node yield of rectal cancer surgery. METHODS: Data for patients who underwent neoadjuvant chemoradiotherapy followed by surgery for resectable rectal cancer from June 1992 to June 2009 were reviewed. The primary outcomes measured were the number of lymph nodes retrieved, their status, and patient survival. RESULTS: In total, 345 patients underwent neoadjuvant chemoradiotherapy followed by surgery, and 95 patients had surgery alone. Neoadjuvant chemoradiotherapy decreased both the median (range) number of lymph nodes retrieved (7 (1-33) versus 12.5 (0-44) respectively; P < 0.001) and the number of positive lymph nodes (0 (0-11) versus 0 (0-16); P = 0.001). After neoadjuvant chemoradiotherapy, the number of retrieved lymph nodes was inversely correlated with tumour regression, and with the interval between treatment and surgery. The 5-year overall and disease-free survival rates were 86.5 and 79.1 per cent respectively. After neoadjuvant therapy, lymph node status was found to be an independent predictor of survival, whereas the number of retrieved lymph nodes did not represent a prognostic factor for either overall or disease-free survival. CONCLUSION: Low lymph node count after neoadjuvant chemoradiotherapy for rectal cancer does not signify an inadequate resection or understaging, but represents an increased sensitivity to the treatment.

Transanal endoscopic microsurgery after neoadjuvant radiochemotherapy for locally advanced extraperitoneal rectal cancer: short-term morbidity and functional outcome.

BACKGROUND: Transanal endoscopic microsurgery (TEM) after radiochemotherapy (RCT) has been reported in selected cases of locally advanced rectal cancer as an alternative to traditional radical resection with total mesorectal excision with a curative intent or as diagnostic tool to confirm a pathological complete response of the primary tumor. No study has evaluated functional outcome after TEM in preoperatively irradiated patients. METHODS: This study was designed to evaluate short-term morbidity (according to Clavien's classifications) and establish (by a questionnaire) continence and evacuative function after RCT and TEM, at 1 year from surgery, analyzing the impact of RCT on postoperative outcomes. Patients with locally advanced rectal cancer treated by RCT and TEM (group 1) or with early T1 or adenomas treated only by TEM (group 2) entered this cohort comparative study. RESULTS: Twenty-two patients entered the study as group 1 and 25 as group 2. No postoperative mortality occurred. The morbidity rate was 36.4 % in group 1 vs. 16 % in group 2 (p = 0.114). The rate of suture dehiscence was 22.7 % in group 1 vs. 4 % in group 2 (p = 0.068). No grade III complications, reoperation, or hospital readmission within 30 days was recorded in either group. One year after surgery, continence and evacuative scores in group 1 were 1.05 ± 1.25 and 24.72 ± 2.79, respectively, which were similar to group 2 (p = 0.081 and 0.288, respectively). CONCLUSIONS: TEM after RCT in selected rectal cancer patients has an acceptable morbidity and functional results at 1 year from surgery. Preoperative irradiation could increase postoperative short-term morbidity, but it does not seem to influence evacuative or sphincter function after 1 year from surgery.

Differentiating hepatocellular carcinoma from dysplastic nodules at gadobenate dimeglumine-enhanced hepatobiliary-phase magnetic resonance imaging.

PURPOSE: We evaluated whether the addition of delayed phase imaging (DPI) gadobenate dimeglumine-enhanced MRI to dynamic postcontrast imaging improves the characterization of small hepatocellular carcinoma (HCC) and the differentiation between HCC, high grade dysplastic nodules (HGDN), and low grade dysplastic nodules (LGDN). METHODS: Twenty-five cirrhotic patients with 30 nodules (16 HCC, 8 HGDNs, and 6 LGDNs; maximum size of 3 cm) were included in this retrospective study. The diagnostic reference standard was histology. All the patients underwent MRI both prior to and following intravenous administration of gadobenate dimeglumine. The lesions were classified as hypointense, isointense, hyperintense on DPI for qualitative assessment. In the quantitative analysis the relative tumor-liver contrast to noise ratio (CNR) of the lesions on DPI was calculated. RESULTS: All HCCs were hypointense on DPI while only 8 (57.1%) of 14 DNs were hypointense and only 1 of 6 (16.6%) LGDNs was hypointense. There was a statistically significant difference in the hypointensity on DPI between HCCs and DNs (p = 0.003) in the qualitative analysis but not in the CNR values while there was a strong statistically significant difference in the hypointensity on DPI in the qualitative (p = 0.00001) and quantitative analysis (p < 0.05) between LGDNs and the group obtained by unifying HGDNs and HCCs. CONCLUSION: DPI is helpful in differentiating HCCs and HGDNs from LGDNs. Demonstration of hypointensity on DPI should raise the suspicion of HGDN or hypovascular HCC in the case of nodules with atypical dynamic pattern.

Lymphoepithelial cyst of the pancreas: case report and review of the literature.

BACKGROUND AND STUDY AIMS: Lymphoepithelial cyst of the pancreas (LCP) is a rare, benign cyst mimicking pseudocyst or cystic neoplasm. Literature describing LCP is limited to case or brief series reports, and the natural history of this condition is largely unknown. A literature review was carried out in order to elucidate the clinical, pathological and biochemical features of LCP. The aim of this study was to define diagnostic criteria and treatment. METHODS: A Medline and Pubmed search was conducted by using the key-words "lymphoepithelial cyst" and "pancreas". The articles found were accurately examined and all details regarding clinical and pathological features were included in a data-base. Furthermore, a case recently observed in our unit was added to the review. RESULTS: Ninety-two cases of LCP were found in the worldwide literature, including the case that we observed. LCP occurs more frequently in males (M:F=5.5:1), its preferred site is the tail of the pancreas, and its size ranges between 2 and 10centimetres. Histologically, it is a true cyst delineated by a keratinizing squamous epithelium surrounded by lymphoid tissue. LCP is asymptomatic in the majority of cases and preoperative diagnosis is complicated by a lack of specific radiological features of the disease. An accurate preoperative diagnosis can only be made by obtaining cytological specimens and placing them in the hands of a pathologist who is familiar with the cytological appearances of the disease. CONCLUSIONS: LCP is a rare lesion worldwide, without any prevalence in different countries or in different ethnic groups. Understanding the features of LCP, making an accurate diagnosis and differentiating it from cystic neoplasm preoperatively is vital, as when it is diagnosed certainly, a conservative treatment is justified. Otherwise, radical surgery in the form of pancreatic resection is required to exclude the diagnosis of pancreatic cystic neoplasm.

Optimizing clinical care in patients with advanced soft tissue sarcoma: a phase II study of a new schedule of high-dose continuous infusion ifosfamide and doxorubicin combination.

BACKGROUND: Ifosfamide and doxorubicin combination is an active regimen for patients with advanced soft tissue sarcomas (STS) but is burdened by high toxicity. A phase II trial was designed to assess the activity of continuous infusion ifosfamide and doxorubicin combination. PATIENTS AND METHODS: Thirty-four chemotherapy-naive patients with advanced STS were treated with ifosfamide (13 g/m(2)/12 days as continuous infusion) and doxorubicin (75 mg/m(2) on day 8) every 28 days with granulocyte colony-stimulating factor. RESULTS: The major toxicity was hematological: grade 3/4 neutropenia, anemia and thrombocytopenia occurred in 63, 30 and 12% of patients, respectively. The disease control rate was 68% and the median time to progression was 7.1 months. Among leiomyosarcomas, 2 partial responses and 4 stable diseases were observed. CONCLUSIONS: Our study confirms that the ifosfamide and doxorubicin combination has a very low non-hematological toxicity profile. This regimen attained a high disease control rate with moderate activity. Further investigation into leiomyosarcoma is warranted.

Study of spontaneous recurrent seizures and morphological alterations after status epilepticus induced by intrahippocampal injection of pilocarpine.

Epileptic seizures are clinical manifestations of neuronal discharges characterized by hyperexcitability and/or hypersynchrony in the cortex and other subcortical regions. The pilocarpine (PILO) model of epilepsy mimics temporal lobe epilepsy (TLE) in humans. In the present study, we used a more selective approach: microinjection of PILO into the hilus of the dentate gyrus (H-PILO). Our main goal was to evaluate the behavioral and morphological alterations present in this model of TLE. Seventy-six percent of all animals receiving H-PILO injections had continuous seizures called status epilepticus (SE). A typical pattern of evolution of limbic seizures during the SE with a latency of 29.3 ± 16.3 minutes was observed using an analysis of behavioral sequences. During the subsequent 30 days, 71% of all animals exhibited spontaneous recurrent seizures (SRSs) during a daily 8-hour videotaping session. These SRSs had a very conspicuous and characteristic pattern detected by behavioral sequences or neuroethiological analysis. Only the animals that had SE showed positive Neo-Timm staining in the inner molecular layer of the dentate gyrus (sprouting) and reduced cell density in Ammon's horn pyramidal cell subfield CA1. However, no correlation between the intensity of sprouting and the mean number and total number of SRSs was found. Additionally, using Fluoro-Jade staining, we observed neurodegeneration in the hilus and pyramidal cell subfields CA3 and CA1 24 hours after SE. These data indicate that H-PILO is a reliable, selective, efficient, low-mortality model that mimics the acute and chronic behavioral and morphological aspects of TLE.

Functional coupling of parietal α rhythms is enhanced in athletes before visuomotor performance: a coherence electroencephalographic study.

It has been shown that elite pistol shooters are characterized by a power increase of wide cortical electroencephalographic (EEG) alpha (about 8-12 Hz) and beta (about 14-35 Hz) rhythms during the preparation of air pistol shots, possibly related to selective attentional and "neural efficiency" processes [Del Percio C, Babiloni C, Bertollo M, Marzano N, Iacoboni M, Infarinato F, Lizio R, Stocchi M, Robazza C, Cibelli G, Comani S, Eusebi F (2009a) Hum Brain Mapp 30(11):3527-3540; Del Percio C, Babiloni C, Marzano N, Iacoboni M, Infarinato F, Vecchio F, Lizio R, Aschieri P, Fiore A, Toràn G, Gallamini M, Baratto M, Eusebi F (2009b) Brain Res Bull 79(3-4):193-200]. Here, we tested the hypothesis that such processes are associated with an enhanced functional coupling of posterior cortical regions involved in task-relevant attentional processes and visuo-motor transformations. To this aim, between-electrodes spectral coherence was computed from spatially enhanced EEG data collected during a previous study (i.e. right handed 18 elite air pistol shooters and 10 matched non-athletes; augmented 10-20 system; surface Laplacian estimation). Theta (about 4-6 Hz), low-frequency alpha (about 8-10 Hz), high-frequency alpha (about 10-12 Hz), low-frequency beta (14-22 Hz), high-frequency beta (23-35 Hz), and gamma (36-44 Hz) bands were considered. Statistical results showed that intra-hemispheric low-frequency alpha (parietal-temporal and parietal-occipital regions), high-frequency alpha (parietal-temporal and parietal-occipital regions), high-frequency beta, and gamma (parietal-temporal regions) coherence values were stable in amplitude in the elite athletes but not in the non-athletes during the preparation of pistol shots. The same applies to inter-hemispheric low-frequency alpha (parietal regions), high-frequency alpha (parietal regions), high-frequency beta and gamma coherence values. These findings suggest that under the present experimental conditions, elite athletes are characterized by the stabilization of functional coupling of preparatory EEG rhythms between "visuo-spatial" parietal area and other posterior cortical areas.