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We study the specific features of the organization of the functional brain networks of children with autism spectrum disorder (ASD) by analyzing at the source level the data obtained in the EEG experiment in the resting-state paradigm. We pay special attention to age-related changes in the characteristics of functional networks during the particularly important age period from early childhood to adolescence. The analyzed experimental groups consisted of 148 ASD children and 173 neurotypical children that were considered as a control group. In the theta band, we revealed an age-independent functional connectivity pattern, consisting of the brain areas responsible for emotions and consciousness, where the strength of connections is higher in neurotypical children compared to ASD children. Moreover, we discovered lower network global clustering in the delta + theta band in ASD children. Thus, more segregated, but more highly connected subnets are formed in the delta + theta band in neurotypical individuals compared to ASD ones. We can suggest increased control over emotions and stronger interaction between the emotional and conscious domains in neurotypical children. In the extended alpha band, we revealed an age-dependent functional connectivity pattern, demonstrating hyper-activation in the ASD group for ages below 6–7 years old and hypo-activation—for older ages. Also, we discuss the development of effective approaches to autism therapy, which should be based on the normalization of aberrant functional connections. [ABSTRACT FROM AUTHOR]

We aimed to evaluate changes in EEG power upon presentation of pleasant and unpleasant C-tactile stimulation to patients in acute and subacute coma, as well as in the vegetative state. The study involved 50 unconscious patients and 35 participants in the control group aged 21–46 years. The study included the registration of a background EEG with eyes closed for 1–2 min, as well as after presentation of tactile stimulation of two types (stroking with a soft brush, stroking with a hard brush) at a constant speed of 2–4 cm/s on the outer surface of the right forearm. The subjective assessment of stimuli by conscious subjects was also rated. EEG spectral power indices were evaluated in 19 sub-bands with a bandwidth of 1 Hz (2–20 Hz). The study revealed two types of responses to tactile stimulation: the first type is not specific to the type of tactile stimulation, accompanied by an increase in alpha-rhythm power (10–12 Hz) in subacute and vegetative states and beta-rhythm (14–20 Hz)—only in vegetative; the second type of reaction is accompanied by a decrease in theta rhythm power (4–6 Hz) in the central regions in response to stimulation of the c-tactile system with a soft brush and is observed only in patients in the subacute period. The selective response to stimulation of the c-tactile system observed in patients in the subacute phase of the coma was manifested on the EEG by a decrease in the theta rhythm power in the central regions. The increase in beta-rhythm power serves as a universal indicator of sensorimotor activation and intention to movement and is most pronounced in patients in a vegetative state. An increase in alpha-rhythm power shows the activation of working memory, as well as the suppression of other processes not related to the perception of tactile effects and is most pronounced in patients in the subacute phase and vegetative state. The results may be used for further development of AI-based tools for evaluation of the consciousness level and outcome prediction. [ABSTRACT FROM AUTHOR]

The importance of touch in human social development and interpersonal interactions is widely recognized, yet the underlying neurological processes remain relatively unexplored. To better understand these mechanisms, we analyzed functional magnetic resonance imaging (fMRI) data to investigate how affective touch influences brain activity. Our study employed independent component analysis (ICA) and cluster analysis to identify brain components that exhibit significant changes following tactile stimulation. These components were then mapped to large-scale brain networks, focusing on those with the most pronounced spatial intensity differences. Our findings highlight the crucial role of distinct brain networks in processing tactile sensations. Notably, we observed significant changes in the default mode network (DMN) activity, particularly in the control group, after the touch experiment. Additionally, specific alterations were detected in the amygdala, cuneus, and orbitofrontal cortex. This study sheds light on the neurological foundations of tactile experiences and their potential impact on behavior and emotional states. Understanding these processes could inform the development of therapeutic strategies that leverage touch to alleviate stress and enhance mental health. [ABSTRACT FROM AUTHOR]

Affective touch plays an important role in human social bonding, affiliative behavior, and in general emotional well-being. A system of unmyelinated low-threshold mechanosensitive C-type afferents innervating hairy skin (C-tactile or CT system) is postulated to provide the neurophysiological background of affective touch perception. C-tactile afferents respond optimally to soft and slow strokes, and this response correlates positively with pleasure ratings of tactile stimuli. As gentle touch is consistently associated with oxytocin release further promoting prosocial behavior, it has been suggested that this effect is mediated by the response of C-tactile afferents. This study assesses a possible link between CT-optimal touch, its subjective pleasantness, EEG indices of cortical arousal, and peripheral oxytocin response. EEG was recorded in 28 healthy volunteers during resting state and tactile stimulation[gentle slow brush strokes on forearm (CT-targeted touch) and palm (non-CT-targeted touch)]. Saliva samples were collected before and after the touch stimulation. Oxytocin concentration increase was significantly associated with greater subjective ratings of CT-targeted touch but not of non-CT-targeted touch, and with lower peak alpha frequency values indicating decreased cortical arousal. The findings suggest that CT-targeted stimulation triggers oxytocin release but only when the touch is perceived at an individual level as having clearly positive affective salience. This corresponds to previous studies reporting that oxytocin response to touch can be related to different personality factors, and bears important implications for planning touch-based interventions in social and medical care. [ABSTRACT FROM AUTHOR]