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Background. Even though mild cognitive impairments are common in patients with attention deficit hyperactivity disorder (ADHD), there are no studies of morphometric brain parameters in children with ADHD and comorbid mild cognitive impairments. Objective. The aim of the study is to determine and perform comparative analysis of MR-morphometric brain parameters in children with ADHD depending on the presence or absence of comorbid mild cognitive impairments. Methods. Participants are children aged from 7 to 8 years with ADHD without comorbid pathology (CP), ADHD with mild cognitive impairment (MCI), MCI without ADHD, and healthy children. All participants underwent brain magnetic resonance imaging followed by morphometry to obtain quantitative parameters of large brain structures, cerebral cortex gyri, basal ganglia, cerebellum, and lateral ventricles. Results. 90 children were examined. ADHD with MCI group has shown significant decrease in the volumes of caudate nuclei bilaterally and hippocampus on the right, as well as decrease in the volumes of right superior parietal gyrus, supramarginal gyrus, and frontal cortex. ADHD without CP group has shown different changes: decrease in the volume of putamen on both sides and thalamus on the left, increase in the volume of six and decrease in the volume of the cortex of four gyri, cortex thinning of four gyri with cortex thickening of one gyrus, volume increase of four cerebellar lobules. MCI without ADHD group has shown bilateral enlargement of lateral ventricles, decrease in the volume of right pallidum and seven gyri cortex, mostly on the right side, as well as decrease in the volume of four cerebellar lobules. Direct comparison between the two ADHD groups has shown significant differences up to lower total cortex volume with 5 gyri of left hemisphere and 7 gyri of right hemisphere in the ADHD with MCI group. Participants of ADHD groups compared to healthy individuals and the MCI without ADHD group did not show any age-related dynamic decrease in the volumes of cerebral cortex. Conclusion. ADHD is characterized by parallel presence of two pathogenetic processes: cerebral cortex hypoplasia and delayed age-related changes in other areas. Significant differences in morphometric parameters were revealed between ADHD without CP and ADHD with MCI. It suggests individual treatment for such patients and revision of approaches to morphometric brain studies in patients with ADHD. Enlargement of lateral ventricles in MCI may indicate the effect of perinatal pathology on these conditions’ etiology.

The use of magnetic resonance imaging in morphometry, as quantitative assessment of brain parameters (thickness, surface area, volume), allows to detect changes in many neuropsichiatric conditions that were previously considered intact. This article provides data on neuroimaging brain morphometry and effective use of this method in neurosciences.

Background. The role of recently discovered neurospecific peptides in the pathogenesis of acute and progressive neurologic disorders, their neuroprotective features, and possibilities to use them as markers for the course and prognosis of certain diseases have been actively studied in recent decades. However, neurospecific peptides are almost not studied in chronic residual diseases. In our study we measured the levels of neurospecific peptides and some other markers to achieve understanding of general neurophysiological trends in congenital and acquired chronic non-progressive brain pathology with reference to the selection of relevant groups — study objects. Objective. The aim of the study is to study patterns of neurospecific peptides, neurotransmitters and neuroreceptor markers distribution in the serum of children with various pathogenetic variants of chronic neuropathology. Methods. The study included children from 3 to 16 years old with different pathologies. The sample was divided into groups by pathology type: no sensory and neurological disorders, congenital sensory deficit due to mutation of genes expressed and not expressed in the brain, early acquired sensory deficit of multifactorial nature, congenital mild and severe organic disorders of central nervous system (CNS) in residual stage without baseline sensory deficit, acquired functional CNS disorders without baseline organic defect and sensory deficit. The following laboratory data (neurophysiological components) was studied: nerve growth factor, brain-derived neurotropic factor, neurotrophin-3, neurotrophin-4, neuregulin-1-beta-1, beta-secretase, sirtuin-1, synaptophysin, neuronal nitric oxide synthase, and anti-NR2 glutamate receptor antibodies. The parameters of cognitive activity, sense of vision, sense of smell, and acoustic sense were also evaluated. Results. The study included 274 participants. Neuropeptides and markers have shown a variable degree and range in the group spectrum of differences from normal levels. The most variable in the examined sample was NO-synthase, as well as levels of both neurotrophins, beta-secretase, and glutamate receptor marker. All visual deficits were associated with increased NO-synthase levels (p < 0.001). Neuroplasticity peptides (beta-secretase, neurotrophin-3 and 4) have been activated in all pathological conditions. Nerve growth factor and brain-derived neurotropic factor were specifically activated in mild organic CNS lesions (mild cognitive impairments), while neuregulin — in congenital genetically determined visual deficits. There was no specific activation of neuropeptides and NO-synthase level tended to decrease in cases of severe CNS lesions. Conclusion. The study results suggest that all types of early visual impairment are associated with increased physiological neuronal activity, and non-organic neurological functional disorders — mainly with increased physiological synaptic activity. General neuroplasticity processes were activated in all cases of visual deficits but more specific. However, more specific and well-studied processes were activated in mild organic CNS lesions, and neuroplasticity processes did not activate adequately in severe organic CNS lesions probably due to the limited neuronal and synaptic resources.

Background. The study of digital activity correlation with cognitive-emotional features, as well as with other parameters of adolescents’ life-activity in non-capital regions of Russian Federation remains relevant.Objective. The aim of the study is to analyze the digital activity structure in adolescents and its correlation with cognitive-emotional features, school performance and social and age factors.Methods. Participants are secondary school students of the 8th–11th grades. Digital activity was examined via online survey among adolescents. We took into account the use of social media, information search, watching videos on the Internet, using of messengers, playing games with electronic devices. Cognitive features (memory, thinking, executive functions, sensory information procession, reading and speech, understanding of emotions, decision-making) and emotional state of adolescents (anxiety) were evaluated by clinical psychologists via various tests. School performance was determined by the recent results of the school quarters/semester finished by the time of the survey. Social and age factors included regular out-of-school physical activity and family structure (complete/ incomplete).Results. We have examined 438 teenagers. 53 (12%) respondents spend more than 5 hours a day with digital devices on weekdays, 133 (30%) — on weekends, 147 (34%) — during the holidays. Structure of digital activity during weekdays (≥ 1 hour) among adolescents was the following: activity in social media prevailed (63.5% of respondents), fewer teenagers searched for information or watched videos on the Internet (47.3 and 42.9%, respectively), about a third (34.9%) played via electronic devices. Structure of digital activity changed over the weekend and during the holidays. We have revealed differences between the information search activity and the volume of short-time memory, understanding the verbal messages, and verbal-logical operations level. Adolescents with different levels of computer gaming activity have shown diversity in sensomotor reaction speed, visuospatial memorization accuracy, number of errors in high-speed reading, reading pace, and understanding text basic meaning.Conclusion. The greater time of digital activity among 8th–11th grades students is associated with negative results of cognitive activity and school performance.