Frontopolar activation during face-to-face conversation: an in situ study using near-infrared spectroscopy.
ABSTRACT Near-infrared spectroscopy (NIRS) is a functional brain imaging technique for monitoring brain activation in a natural setting using near-infrared light, and hence, is considered to have some advantages for studies of brain function during social interactions such as face-to-face conversation compared with functional magnetic resonance imaging and positron emission tomography, which have methodological constraints for studying brain mechanisms underlying social interactions: subjects have to lie down on a bed in a small gantry during examination. The purpose of this study was to validate the possible use of NIRS as a functional brain imaging technique for studying social interactions in a natural setting; therefore, we investigated frontal and temporal lobe activation during face-to-face conversation in healthy subjects in the sitting position. The frontal and superior temporal regions were activated during face-to-face conversation, with higher activity in the speaking segments than in the mute segments during conversation particularly in frontopolar NIRS channels. The magnitude of frontopolar activity negatively correlated with the cooperativeness score of the subjects assessed using the temperament and character inventory. These results demonstrated the successful monitoring of brain function during realistic social interactions using NIRS and interindividual differences in frontopolar activity during conversation in relation to the cooperativeness of an individual.
SourceAvailable from: Satoshi Tanaka[Show abstract] [Hide abstract]
ABSTRACT: Functional neuroimaging techniques are widely used to elucidate changes in brain activity, and various questionnaires are used to investigate psychopathological features in patients with eating disorders (ED). It is well known that social skills and interpersonal difficulties are strongly associated with the psychopathology of patients with ED. However, few studies have examined the association between brain activity and social relationships in patients with ED, particularly in patients with extremely low body weight.BMC Psychiatry 06/2014; 14(1):173. DOI:10.1186/1471-244X-14-173 · 2.24 Impact Factor
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ABSTRACT: Major depressive disorder (MDD) and bipolar disorder (BD) patients show speech characteristics that vary greatly according to mood state. In a previous study, we found impaired temporal and right inferior frontal gyrus (IFG) activation in schizophrenia during face-to-face conversation; no study had, however, previously investigated mood disorders during face-to-face conversation. Here, we investigated frontal and temporal lobe activation during conversation in patients with MDD and BD. Frontal and temporal lobe activation was measured using near-infrared spectroscopy (NIRS) in 29 patients with MDD, 31 patients with BD, and 31 normal controls (NC). We compared continuous activation and rapid change of activation with talk/listen phase changes during the conversation and analyzed the correlation between these indices and clinical variables. Both the MDD and BD groups showed decreased continuous activation in the left dorsolateral prefrontal (DLPFC) and left frontopolar cortices (FPCs); they also showed decreased rapid change in bilateral FPC activation. In the MDD group, the rapid change of activation was positively correlated with Global Assessment of Functioning (GAF) scores. In the BD group, continuous activation was negatively correlated with age of onset. These results indicate that frontal activation during conversation decreases in both MDD and BD. However, both continuous activation and rapid change may reflect the pathophysiological character of MDD and BD; in particular, the reduced amount of rapid change in the right FPC may be related to impaired adaptive ability in MDD.Journal of Psychiatric Research 10/2014; 57. DOI:10.1016/j.jpsychires.2014.06.009 · 4.09 Impact Factor
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ABSTRACT: The human brain is characterized by an evolutionarily new, highly developed neocortex, which has characteristic connections with phylogenically older structures to enable adaptation to complex social environments. Adaptive social behavior requires successful mental representations of the self and others' emotions and intentions. Measurement of brain activity under laboratory-based settings has been the gold standard in previous cognitive neuroscience studies. However, these measurement settings may be sub-optimal if we want to visualize brain function in active individuals in real-world environments. Neuroscience has historically developed through generations of the "sensing brain," "emotional brain," "social brain," and "ego brain." The next generation is the "action brain" combined with "real-world neuroscience" perspective. To enable in situ measurement of the action brain, real-world or two-person neuroimaging techniques are necessary to visualize brain dynamics during natural social situations, such as the presence of others. This review discusses recent literature describing non-human primate (NHP) and human brain functions during active behaviors in social environments. Uncovering the neurobiological mechanisms of the active brain in the presence of others by using real-world neuroimaging will be an important step toward fully understanding the human brain and its mental functions. Copyright © 2014. Published by Elsevier Ireland Ltd.Neuroscience Research 11/2014; DOI:10.1016/j.neures.2014.11.007 · 2.15 Impact Factor