Does alpha phase modulate visual target detection? Three experiments with tACS-phase-based stimulus presentation

In recent years, the influence of alpha (7–13 Hz) phase on visual processing has received a lot of attention. Magneto‐/encephalography (M/EEG) studies showed that alpha phase indexes visual excitability and task performance. Studies with transcranial alternating current stimulation (tACS) aim to modulate oscillations and causally impact task performance. Here, we applied right occipital tACS (O2 location) to assess the functional role of alpha phase in a series of experiments. We presented visual stimuli at different pre‐determined, experimentally controlled, phases of the entraining tACS signal, hypothesizing that this should result in an oscillatory pattern of visual performance in specifically left hemifield detection tasks. In experiment 1, we applied 10 Hz tACS and used separate psychophysical staircases for six equidistant tACS‐phase conditions, obtaining contrast thresholds for detection of visual gratings in left or right hemifield. In experiments 2 and 3, tACS was at EEG‐based individual peak alpha frequency. In experiment 2, we measured detection rates for gratings with (pseudo‐)fixed contrast. In experiment 3, participants detected brief luminance changes in a custom‐built LED device, at eight equidistant alpha phases. In none of the experiments did the primary outcome measure over phase conditions consistently reflect a one‐cycle sinusoid. However, post hoc analyses of reaction times (RT) suggested that tACS alpha phase did modulate RT for specifically left hemifield targets in both experiments 1 and 2 (not measured in experiment 3). This observation requires future confirmation, but is in line with the idea that alpha phase causally gates visual inputs through cortical excitability modulation

Экологический рекреационный потенциал как фактор устойчивого рекреационного природопользования в Крыму

В статье впервые рассмотрены направления комплексного изучения и оценки эколого-рекреационного потенциала территории. Анализ экологической ситуации в Крыму с позиций рекреационного природопользования (РП) включал оценку последствий выбросов загрязняющих веществ в атмосферу, сброса сточных вод вводные объекты. Рассмотрена роль и место природоохранных территорий Крыма в системе РП. При написании статьи использовались методы экологической статистики и картографические методы.У статті вперше розглянуті напрямки комплексного вивчення та оцінки еколого-рекреаційного потенціалу території. Аналіз екологічної ситуації в Криму з позицій рекреаційного природокористування (РП) включав оцінку наслідків викидів шкідливих речовин у атмосферне повітря, скиду стічних вод у водні об'єкти. Розглянута роль та місце природоохоронних територій Криму у системі РП. При написанні статті використовувалися методи екологічної статистики та картографічні методи.The ways of complex research and assessing ecological recreational potential of the territory have been considered in this article for the first time. The analysis of ecological situation in the Crimea from the point of view of the recreational nature management included the consequences of polluting substances in atmosphere, сброс of contaminated sewage into nature objects. The role and place of nature protected territories in the Crimea within the system of recreational nature management have been under the consideration. Ecological statistics and cartographical methods were used in writing this article