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Advanced Neurology MNS in patients with anxiety and depressive symptoms

of the mu rhythm serves as an adequate indicator of MNS With regard to anxiety disorders, no separate studies
activation, and the degree of desynchronization indicates have been conducted on the effect of anxiety on MNS
the level of MNS activity. The degree of desynchronization functioning. Anxiety disorders are becoming more
of the lower beta 1 band (13 – 21 Hz) in the central widespread and are largely accompanied by affective
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scalp regions is sometimes considered an indicator of disorders. However, the most important patterns of social
MNS activity, since it also contains harmonics from the activity, such as empathy, understanding the intentions of
sensorimotor mu rhythm. 21 others, and adaptation to one’s own emotional background,
are affected in patients with anxiety and depressive
However, some researchers have criticized the use of this 44
method to determine MNS activation, pointing out that symptoms. The purpose of this study is to investigate how
a change in the mental state at the functional level can alter
the mu rhythm range intersects with the alpha rhythm and the activity of brain networks. Specifically, we examined
that they cannot always be well differentiated. In addition, changes in the social lives of anxious patients from the
a decrease in mu or alpha rhythm may be associated not viewpoint of mirror neuron activity.
only with the MNS but also with visual attention and other
processes related to visual processing. 22,23 Indeed, when 2. Methods
using mu rhythm suppression as the main indicator of the
MNS, it is necessary to understand the functional features MNS studies typically use experimental paradigms with
of alpha and mu rhythms, take their spatial localization tasks to observe and perform hand gestures. Since, by
into account, carefully approach the choice of baseline, and definition, mirror neurons are activated not only when
monitor not only the central leads but also other areas of performing but also when observing and imagining
the scalp, especially the occipital leads. gestures, examining the reaction of brain activity to these
“mirror” tasks allows us to identify features of mirror
To date, there is limited research on the MNS in system functioning. In our study, we used the reaction of
patients with affective disorders. Most articles on MNS brain rhythm suppression in three frequency ranges when
disorders focus on autism 24-27 and schizophrenia. 28-31 Only implementing “mirror” tasks.
a few studies have explored the MNS features in patients
with borderline personality disorders (BDRs) and major 2.1. Ethics statement
depression 2013. For example, it was demonstrated that This study was approved by the local ethical committees
the MNS tends to be hypofunctional in patients with BDR: of the Institute of Higher Nervous Activity and
The sensorimotor areas and the amygdala were activated Neurophysiology and the Scientific and Practical
more than in control group. 32,33 A few studies have focused Psychoneurological Center. All participants provided
on empathy problems and MNS activity in patients with written informed consent before the start of the study.
bipolar disorder. Patients with bipolar disorder in the
euthymic phase showed reduced MNS activation during 2.2. Participants
a social-cognition task. 34,35 However, MNS activity and its The final sample comprised 47 participants: 24 patients
functional correlates demonstrate the opposite dynamics with anxiety and 23 individuals without any neurological
in the manic phase of disorder. 36-38 In a TMS study, it was or psychiatric diagnoses as the control group. The
demonstrated that MNS activity is increased in the manic demographic information and clinical features are
phase, possibly because of disinhibition, and this was presented in Table 1. The selection criteria for the patient
associated with behavioral consequences. Very limited group were as follows: right-handedness, ages ranges from
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data are available for patients with major depression. Kumar 18 to 45 years, presence of leading anxiety and additional
et al. studied the impact of social isolation on patients with depressive syndrome, specifically diagnosed as F41.0
major depression. Compared to the control group, people
with major depression showed greater activation of the Table 1. Demographical and clinical test scores
amygdala, insula, and ventrolateral prefrontal cortex. Measure Patients (N=24) Control group (N=23)
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In another study, patients with major depression showed
greater intensity of the fMRI signal in the anterior cingulate Gender (female/male) 16/8 15/8
cortex, bilateral superior/middle frontal cortex, and right Age (mean±SD) 29±5.6 28±4.2
angular gyrus than healthy participants. The results from STAI (state anxiety) 52±8 25±3
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a study by Jahangard et al., in turn, showed that TMS STAI (trait anxiety) 56±10 30±3
targeting the lower temporal lobe, which is rich in mirror BDI 18±8 2±2
neurons, improves empathy and reduces depression in Abbreviations: BDI: Beck depression inventory; SD: Standard
patients with depressive disorder. 42 deviation; STAI: State-trait anxiety inventory.

Volume 3 Issue 1 (2024) 3 https://doi.org/10.36922/an.2009