People often change their beliefs by succumbing to an opinion of the majority. Such changes are often referred to as majority influence or conformity. While some previous studies have focused on the reinforcement learning mechanisms of conformity or on its internalization, others have reported evidence of changes in sensory processing evoked by majority opinion. In this study, we used magnetoencephalographic (MEG) source imaging to further investigate the remote effects of agreement and disagreement with the majority. During the first session, participants rated the trustworthiness of faces and subsequently learned how the majority of their peers had previously rated each face. To identify the neural correlates of the post-effect of agreeing or disagreeing with the group, we recorded MEG activity while participants rated faces during the next session. We found MEG traces of past disagreement or agreement with the peer group at the parietal cortices as early as approximately 230 ms after the face onset. The neural activity of the superior parietal lobule, intraparietal sulcus, and precuneus was significantly stronger if the participant’s rating had previously differed from the ratings of his or her peers. The early MEG correlates of disagreement with the majority were followed by activity in the orbitofrontal cortex starting at about 320 ms after the face onset. Altogether, the results reveal the temporal dynamics of the neural mechanism of remote effects of disagreement with the peer group: early signatures of modified face processing were followed by later markers of long-term social influence on the valuation process at the ventromedial prefrontal cortex
В статье рассматривается проблема организации информации в сознании человека, в частности, принципиальная возможность выделения в массиве воспринимаемой и обрабатываемой информации каких-либо структурных единиц, возможность выделения наименьшей, “элементарной” единицы информации применительно к сознанию. Рассматривается процесс восприятия как процесс, в ходе которого получаемая от рецепторов информация последовательно обобщается, сравнивается с накопленным ранее опытом и становится материалом для формирования понятий высокого уровня абстракции. Рассматривается процесс “понимания” понятий, как процесс обратный их формированию – процесс, в ходе которого столкновение сознания с ранее усвоенным понятием приводит к повторному развертыванию многочисленных образов и ассоциаций, которые ранее стали материалом для его формирования. Рассматривается проблема выделения в массиве информации ключевых характеристик, наиболее значимых ассоциативных связей применительно к нормальной психике и патологии шизофренического спектра.
n the healthy human brain, the processing of language is strongly lateralised, usually to the left hemisphere, while the processing of complex non-linguistic sounds recruits brain regions bilaterally. Here we asked whether the anterior temporal lobes, strongly implicated in semantic processing, are critical to this special treatment of spoken words. Nine patients with semantic dementia (SD) and fourteen age-matched controls underwent magnetoencephalography and structural MRI. Voxel based morphometry demonstrated the stereotypical pattern of SD: severe grey matter loss restricted to the anterior temporal lobes, with the left side more affected. During magnetoencephalography, participants listened to word sets in which identity and meaning were ambiguous until word completion, for example PLAYED versus PLATE. Whereas left-hemispheric responses were similar across groups, patients demonstrated increased right hemisphere activity 174–294 msec after stimulus disambiguation. Source reconstructions confirmed recruitment of right-sided analogues of language regions in SD: atrophy of anterior temporal lobes was associated with increased activity in right temporal pole, middle temporal gyrus, inferior frontal gyrus and supramarginal gyrus. Overall, the results indicate that anterior temporal lobes are necessary for normal and efficient lateralised processing of word identity by the language network.
Language is a uniquely human cognitive function which plays a defining role in our psychological and social traits. Despite the obvious importance of language and speech, they remain one of the least understood human cognitive functions with the cortical underpinnings of these crucial skills still obscure. In recent decades, a large amount of data that account for the neural bases of language processes in both children and adults have been acquired through the use of many advanced neurophysiology techniques. These include high-density electroencephalography, magnetoencephalography, functional magnetic-resonance tomography, transcranial magnetic stimulation, transcranial direct current stimulation, and eye-tracking. The combined use of these approaches continues to shed light on brain mechanisms of language acquisition, comprehension and processing, on speech disorders and their treatment, and on interactions between language and other neurocognitive systems and functions. The aim of this Research Topic in Frontiers in Human Neuroscience is to provide a state-of-the-art overview of this diverse and multidisciplinary area of research, with special emphasis on bridging the gap between different methodologies.