Dissociated roles of the inferior frontal gyrus and superior temporal sulcus in audiovisual processing: top-down and bottom-up mismatch detection.

Visual inputs can distort auditory perception, and accurate auditory processing requires the ability to detect and ignore visual input that is simultaneous and incongruent with auditory information. However, the neural basis of this auditory selection from audiovisual information is unknown, whereas integration process of audiovisual inputs is intensively researched. Here, we tested the hypothesis that the inferior frontal gyrus (IFG) and superior temporal sulcus (STS) are involved in top-down and bottom-up processing, respectively, of target auditory information from audiovisual inputs. We recorded high gamma activity (HGA), which is associated with neuronal firing in local brain regions, using electrocorticography while patients with epilepsy judged the syllable spoken by a voice while looking at a voice-congruent or -incongruent lip movement from the speaker. The STS exhibited stronger HGA if the patient was presented with information of large audiovisual incongruence than of small incongruence, especially if the auditory information was correctly identified. On the other hand, the IFG exhibited stronger HGA in trials with small audiovisual incongruence when patients correctly perceived the auditory information than when patients incorrectly perceived the auditory information due to the mismatched visual information. These results indicate that the IFG and STS have dissociated roles in selective auditory processing, and suggest that the neural basis of selective auditory processing changes dynamically in accordance with the degree of incongruity between auditory and visual information.

Primary malignant fibrous histiocytoma of the ascending colon: report of a case.

We report a rare case of primary malignant fibrous histiocytoma (MFH) of the ascending colon. A 66-year-old man presented to our hospital with epigastralgia, and abdominal ultrasonography and computed tomography showed a large soft-tissue mass in the ascending colon. Barium enema and endoscopic examination showed a huge tumor in the ascending colon. At laparotomy, we found a tumor in the ascending colon and performed a right hemicolectomy with en bloc lymph node dissection. The resected specimen contained a tumor measuring 14.5 x 8.0 x 4.5 cm, the cut surface of which was yellowish. Based on histological and immunohistological studies, the tumor was diagnosed as MFH of the ascending colon. To our knowledge, only 20 cases of colorectal MFH, including our case, have been documented, which we review following this case report.

Differential increase in natriuretic peptides in elite dynamic and static athletes.

The echocardiographic measures and plasma concentrations of either atrial natriuretic peptide (ANP) or brain natriuretic peptide (BNP) were compared in elite judo practitioners (static athletes), elite marathon runners (dynamic athletes) and healthy controls to investigate the relationship between the different types of left ventricular (LV) hypertrophy and plasma concentrations of natriuretic peptides in athletes. The LV mass and LV wall thickness of marathon runners and judo practitioners were significantly greater than those of controls. The LV end-diastolic dimension index was significantly larger in the marathon group, but smaller in the judo group. The left atrial dimension (LAD) index was significantly larger only in marathon runners. Plasma BNP concentrations were higher in both the judo and marathon groups than in controls, and positively correlated with LV mass as well as with deceleration time. Plasma ANP concentrations were significantly higher in marathon runners than in the controls and judo groups, and positively correlated with the LAD index, but negatively correlated with ejection fraction. Multivariate analyses showed that the type of athlete and LAD index were independent predictors of plasma BNP and ANP concentrations, respectively. Thus, there is an intimate link between plasma concentrations of natriuretic peptides and cardiac morphology in different types of athletes.