The aim of the presented research is to study the neurocognitive mechanisms of attention distortion with social anxiety (SA). An experiment using the modified Eriksen flanker task is implemented. Facial expressions (congruent and incongruent stimulus sequences) are used as stimuli. When solving a problem, the SA severity, errors, or correct decisions, and the sequence of stimuli vary. The integrative platform "EEG + eye tracking" is used; it has the ability to synchronously register parameters and analyze activity in dynamics. During the experiment, we recorded the stimulus, time, and correctness of the response, parameters of oculomotor activity, as well as the EEG (error-related negativity, ERN). When low and high levels of SA are compared, we find a greater deviation from the target priority for the distractors, an increase in solution time, and a decreasing number of correct decisions (especially under incongruent conditions), as well as a greater frequency and duration of fixations, a total number and amplitude of saccades, an increased target detection period. In the case of erroneous decisions, the ERN component is excessively expressed in subjects with SA. The indicators found are the measures of the neurocognitive mechanisms of SA that characterize the features of distortion of attention and information processing in the context of evaluating target activities (threat monitoring, self-focusing, decreased productivity, multitasking).