The Relationship between Neuropsychological Performance and Level of Direct Current Potential in Patients with Occupational Diseases from Exposure to Physical Factors

Abstract

The aim of the study was to identify the peculiarities of neuropsychological indices disorders depending on changes in the level of constant potential in patients with occupational diseases as a result of physical factors.Materials and methods. The study involved 60 patients with vibration disease caused by local vibration (group I), 106 patients with vibration disease caused by combined exposure to local and general vibration (group II), 101 civil aviation pilots with an established diagnosis of professional sensorineural hearing loss (group III), and 50 healthy men (group IV, comparison group) who were not exposed to vibration and noise due to the specifics of their professional activities. Methods of neuro-energy mapping and neuropsychological testing were used.Results. In groups I–II, compared with group IV, an increase in local levels of constant potential (DC-potential level) in the central, right temporal, and central frontal parts of the brain (2.3 (6.5–3.8) mV; –0.3 (–2.1–2.1); 2.1 (–3.4–6.8) and –0.3 (–3.1–4.3); –2.24 (–6.4–3.8); 0.9 (–3.1–8.5) mV at p = 0.005, 0.007 and 0.004 respectively). Differences in the values of DC-potential level gradients in individuals of group III when compared with group IV reached the level of significance in the central, temporal, occipital leads relative to the central frontal (–5.0 (–13.1–3.8); –4.1 (–9.4–5.1); –2.1 (–10.9–6.6); –6.3 (–15.3–1.8) and 2.9 (–3.0–10.6); 2.2 (–4.5–13.8); 5.6 (–7.6–14.1); –1.4 (–7.5–3.9) mV at p = 0.008; 0.009; 0.009, and 0.007 respectively). Cognitive disorders in patients of groups I–III when compared with group IV correspond to a mild disorder of dynamic, constructive praxis and expressive speech (1.40 (0–1,6); 1.43 (0–1,7); 1.2 (0–1,5) and 0.3 (0–1); 0.2 (0–1); 0.06 (0–1) points at p = 0.008, 0.008 and 0.009 respectively).Conclusions. A common neurofunctional sign of a mild impairment of the cognitive sphere in occupational diseases caused by physical factors is an increase in direct current potential level in the frontal-central and parieto-occipital regions, predominantly of the left hemisphere of the brain.