It is widely known that COVID-19 has a number of prolonged effects on general health, wellbeing, and cognitive functioning. However, studies using differentiated performance measures of cognitive functions are still not widely spread making it hard to assess the exact functions that get impaired. Taking into account the similarities between post-COVID ‘brain fog’ and chemofog, we hypothesized that executive functions (EF) would be impaired. Literature search yielded six studies with 14 effect sizes of interest; pooled effect size was small to medium ( ). Combined with a narrative synthesis of six studies without a comparison group, these results show that EF get impaired after COVID-19; although, in most cases the impairment is transient and does not seem to be severe. These results specify the picture of ‘brain fog’ and may help to discover its mechanisms and ways of helping people with long COVID.

User interaction with a virtual reality system may be accompanied with a sense of presence, the illusion of reality of virtual environment. The emergence of a sense of presence is determined by both technological and psychological factors. The authors show that a sense of presence may depend on the individual characteristics of cognitive control, i.e. the system of metacognition providing cognitive system setting on the solution of specific problems in context. It was found that the expression of a feeling of presence may depend on the efficiency of the control switch functions, interference suppression and updating of working memory. At the same time, the dependence of the severity of the sense of presence on the effectiveness of cognitive control differs in virtual environments with different levels of immersion.

COVID-19 is associated with a range of long-lasting symptoms related to cognitive and psycho-emotional spheres. Even mild cases of the disease can lead to persistent cognitive deficits and deterioration of the psycho-emotional state. The purpose of our study was to examine the presence and frequency of psycho-emotional disorders and cognitive deficits in students who recovered from mild form of COVID-19. A total of 40 COVID-19 survivors and 25 healthy controls participated in our study. We assessed three core cognitive functions (inhibition, working memory, task-switching), reaction time and motor speed. We also assessed depression, anxiety and fatigue with self-report questionnaires. The COVID-19 group manifested increased depression and decreased inhibition in comparison with the controls. Our results show that even in young adults who have recovered from mild COVID-19, there are persisting cognitive and psycho-emotional deficits.