Causal involvement of medial inferior frontal gyrus of non-dominant hemisphere in higher order auditory perception: A single case study.

The medial side of the operculum is invisible from the lateral surface of cerebral cortex, and its functions remain largely unexplored using direct evidence. Non-invasive and invasive studies have proved functions on peri-sylvian area including the inferior frontal gyrus (IFG) and superior temporal gyrus within the language-dominant hemisphere for semantic processing during verbal communication. However, within the non-dominant hemisphere, there was less evidence of its functions except for pitch or prosody processing. Here we add direct evidence for the functions of the non-dominant hemisphere, the causal involvement of the medial IFG for subjective auditory perception, which is affected by the context of the condition, regarded as a contribution in higher order auditory perception. The phenomenon was clearly distinguished from absolute and invariant pitch perception which is regarded as lower order auditory perception. Electrical stimulation of the medial surface of pars triangularis of IFG in non-dominant hemisphere via depth electrode in an epilepsy patient rapidly and reproducibly elicited perception of pitch changes of auditory input. Pitches were perceived as either higher or lower than those given without stimulation and there was no selectivity for sound type. The patient perceived sounds as higher when she had greater control over the situation when her eyes were open and there were self-cues, and as lower when her eyes were closed and there were investigator-cues. Time-frequency analysis of electrocorticography signals during auditory naming demonstrated medial IFG activation, characterized by low-gamma band augmentation during her own vocal response. The overall evidence provides a neural substrate for altered perception of other vocal tones according to the condition context.

[Safety and Efficacy of Keishi-Bukuryo-Gan in Patients with Spontaneous Intracerebral Hemorrhage during the Acute Period:CT Image-Based Analysis of the Clearance of Hematoma].

BACKGROUND: Keishi-Bukuryo-Gan(KBG)is a traditional Japanese(Kampo)formula used to improve microcirculation and a congestive condition called "Oketsu". KBG is also used to prevent the development of atherosclerosis. Many patients with intracerebral hemorrhage(ICH)have comorbid diseases related to atherosclerosis;thus, KBG may be a treatment option for ICH. OBJECTIVE: The aim of this study was to investigate whether the administration of KBG in patients with ICH during the acute phase affects the course of absorption of ICH, detected using computed tomography(CT). MATERIAL AND METHODS: We identified 308 patients with ICH who were diagnosed and treated at our institution from April 2013 to June 2016. Among them, 53 patients were chosen based on the accessibility of CT images, patient background, and past history. The volume and CT value of the hematoma were analyzed at admission, one week(six to eight days)after admission, and two weeks(thirteen to sixteen days)after admission. RESULTS: There were no significant differences between KBG and non-KBG patients in terms of the background parameters, hematoma volume, or CT value at admission. However, there were significant differences in both the volume reduction ratio(non-KBG=64.3±8.4%, KBG=48.5±14.5%, p=0.03)and CT value(non-KBG=48.5±4.6HU, KBG=44.0±7.0HU, p=0.04)two weeks after admission. CONCLUSION: Significant improvement in the absorption of ICH was observed in KBG patients. To our knowledge, this is the first report that shows the facilitative effect of KBG on intracranial hematoma clearance during the acute phase.