Boris B. Velichkovsky

Background. Aging is associated with decline in various cognitive functions, including task switching – the ability to shift quickly between tasks and mindsets. Previous research has shown that older adults exhibit less efficient task switching. Mathematical modeling of cognitive processes involved in switching between tasks may shed light on the sources of switching inefficiency in normal and pathological cognitive aging.

Objective. To investigate possible sources of task-switching decline in normal and pathological (mild cognitive impairment, MCI) cognitive aging using the Diffusion Model (DM). 

Design. 57 young adults, 34 healthy older participants, and 5 MCI-diagnosed older participants performed the commonly used Number-Letter switching task. Reaction times (RT) and accuracy were measured and Diffusion Models were fitted to individual reaction time distribution to obtain parameters characterizing processes involved in task switching: active, controlled task-set reconfiguration; passive, automatic task-set inertia; and response caution. 

Results. Older age and MCI-pathology-related effects on switching efficiency were found for RT and, partly, for accuracy. After controlling for possible age differences between the two older groups, active processes of task-set reconfiguration had a clear MCI-related deficit, while passive, automatic task-set inertia components only exhibited a general effect of aging (pathological or not). Response caution was only related to older age, with no MCI effect.

Conclusion. Effortful task-set reconfiguration is sensitive to both age and MCI pathology, while passive processes of task-set inertia dissipation is only subject to age changes. The results support the idea of different dynamics of controlled and automatic cognitive processes in normal and pathological (MCI) aging.

Background. Mastering a first language at school is mediated by the regulatory abilities of pupils. An open question is how the executive functions implementing conscious self-regulation are related to language competences.

Objective. To study the relationship between basic executive functions (switching, inhibition, working memory updating, and error correction) and language competences.

Design. A sample of 104 Russian middle school children (aged 13–15 years) performed three cognitive tasks assessing basic executive functions and two tasks assessing language competences in the areas of punctuation, spelling, morphology, syntax, semantics, vocabulary, and style.

Results. Inhibitionwas mostly related to punctuation, spelling, and morphology competences and was most important in the first competences task, requiring the recognition of errors. Switchingwas mostly related to the competences in syntax, reflecting the importance of switching attention between alternative syntactic structures. Working memory updatingwas the most important executive function related to language competences, with a heavy focus on higher-level lexical, semantic, and stylistic competences. The role of updating was especially important in the second competences task, which required generation of well-formed sentences. Error correctionwas mostly relevant for the recognition of language errors.

Conclusion. While inhibition and switching affect aspects of constructing the surface form of a sentence, working memory is preferentially related to the construction of semantically appropriate sentences. Error monitoring and correction are generally related to the recognition of language errors. Conscious self-regulation and its cognitive mechanisms are systematically related to the development of native language competences in middle school.

Background. The sense of presence is an important aspect of interaction with virtual reality applications. Earlier we suggested that presence can depend on cognitive control. The latter is a set of meta-cognitive processes which are responsible for configuring the cognitive system for the accomplishment of specific tasks with respect to a given context. In particular, cognitive control helps in preventing interference from the task-irrelevant variables.

Objective. is study aimed at investigation of the possible relationship between interference control and aspects of presence.

Design. Thirty-nine subjects (32 female and 7 male, aged 18 to 27 years) participated in the study. The subjects were assessed via a battery of interference control tasks (Flanker Task, Go/No Go task, antisaccade task) and performed a virtual scenario (navigating within an array of randomly placed virtual digits in correct numerical order) in high-immersion (CAVE) and low-immersion (standard computer display) virtual environments. Afterwards, the subjects completed a Russian version of the ITC-Sense of Presence inventory.

Results. We found that interference control is generally related to the sense of presence, especially in the CAVE (high-immersion) environment. Sensory interference control was most strongly associated with various aspects of presence (overall presence score, spatial presence, and emotional involvement). Motor interference control was associated with spatial presence and emotional involvement, but this relationship was weaker than was the case with sensory interference control. Low-immersion virtual environments attenuate some of these links between interference control and presence so that only sensory interference control remains a notable predictor of presence.

Conclusion. Interference control is positively associated with presence in virtual environments with varying immersion levels. is may reflect a more general cause-and-effect relationship between cognitive control and the feeling of presence in virtual reality.

Background. Working memory (WM) seems to be central to most forms of high-level cognition. This fact is fueling the growing interest in studying its structure and functional organization. The influential “concentric model” (Oberauer, 2002) suggests that WM contains a processing component and two storage components with different capacity limitations and sensitivity to interference. There is, to date, only limited support for the concentric model in the research literature, and it is limited to a number of specially designed tasks.

Objective. In the present paper, we attempted to validate the concentric model by testing its major predictions using complex span and updating tasks in a number of experimental paradigms.

Method. The model predictions were tested with the help of review of data obtained primarily in our own experiments in several research domains, including Sternberg’s additive factors method; factor structure of WM; serial position effects in WM; and WM performance in a sample with episodic long-term memory deficits.

Results. Predictions generated by the concentric model were shown to hold in all these domains. In addition, several new properties of WM were identified. In particular, we recently found that WM indeed contains a processing component which functions independent of storage components. In turn, the latter were found to form a storage hierarchy which balances fast access to selected items, with the storing of large amounts of potentially relevant information. Processing and storage in WM were found to be dependent on shared cognitive resources which are dynamically allocated between WM components according to actual task requirements. e implications of these findings for the theory of WM are discussed.

Conclusion. The concentric model was shown to be valid with respect to standard WM tasks. The concentric model others promising research perspectives for the study of higher- order cognition, including underlying neurobiological mechanisms. 

A major risk factor for late-onset Alzheimer’s type dementia (DAT) is the carriage of the ε4 allele of the apolipoprotein E (ApoE) gene. Identifying cognitive deficits in healthy ApoE-ε4 carriers is valuable in order to develop interventions to prevent them from developing DAT. Existing evidence about cognitive deficits in the domains of episodic memory and cognitive control specific to ApoE-ε4 is contradictory.

The objective of our research was to assess episodic memory and cognitive control in healthy ApoE-ε4 carriers.

Cognitively healthy ApoE-ε4 carriers (13 ε4/ε4 heterozygotes) and noncarriers (22 ε3/ε3 homozygotes), who were matched on age and family history of DAT, were compared on episodic-memory and cognitive-control tasks. Episodic-memory tasks were verbal and visual recognition tasks with a systematic variation of distractor-to-target similarity. Executive functions were assessed by a task for updating working memory, an inhibition task, and a switching task. Working-memory capacity was also assessed.

The results showed that executive functions were generally not impaired in the carriers, but carriers showed a specific increase in accuracy-related switch costs. Workingmemory capacity was not reduced in the carriers. In the domain of episodic memory, the carriers were found to make more errors with phonetic distractors in the verbal episodicmemory task. They also tended to make more errors with visually dissimilar distractors in the visual episodic-memory task.

The results are indicative of an episodic-memory deficit specific to the carriage of ApoE-ε4. This deficit may be driven either by deficits in storage or by deficits in the encoding of the to-be-remembered material. Contradictory results concerning the presence of an episodic-memory deficit obtained in previous studies may stem from small effect sizes, the use of specific materials, and the employment of attention-intensive encoding strategies. The carriers also showed a switching deficit that possibly is related to difficulty in retrieving task rules from episodic memory. Existing empirical contradictions concerning the presence of an executive deficit in carriers may in part depend on the extent to which tasks used to assess an executive deficit draw on the switching function. In this study, there was no general executive deficit in the carriers of ApoE-ε4.

Measuring resilience to stress (or stress resistance) validly and reliably is an important theoretical and practical problem. Process-oriented stress theories assume that primary and secondary appraisals play an important role in determining the level of resilience. In the present study, a model of resilience based on the analysis of the interplay between primary and secondary appraisal processes is developed. Resilience is high if benign primary appraisals of taxing situations are accompanied by secondary appraisals of coping resources as being sufficient for controlling stressors. In an implementation of the model, the quality of primary appraisals is assessed through the assessment of anxiety, anger and depression, which characterize the most typical cognitive-emotional reactions to demanding situations. The assessment of secondary appraisals is restricted to the analysis of psychophysiological (functional) resources, which are involved in all forms of coping activities. The implementation of the model gives rise to a measure of resilience, which is shown to successfully predict the outcome of the stress process in a sample of Russian police officers.

Background. Fatigue is the most common complaint by children both during and after cancer treatment, but in Russia, there is no reliable method for assessing fatigue. 

Objective. To develop a Russian version of the Turkish Scale for the Assessment of Fatigue in Pediatric Oncology Patients Ages 7-18.

Design. Our first step was to translate all the items of the Turkish questionnaire into Russian. Then, through discussion, we created a single proposition for each item. The next step was obtaining expert opinions to assess the validity. Once the expert estimates agreed, a pilot version of the questionnaire was formed. The next step was to collect a large sample of patients to study the reliability and validity of the questionnaire. 

Results. As a result of factor analysis, three factors were identified. The first factor was "fatigue associated with actions;" the second was "fatigue as feeling;" and the third was "fatigue associated with sleep difficulties." The children's and parents’ versions had the same factor structure. 

Conclusion. This study showed the possibility of using the questionnaire in a Russian sample. That’s why it is necessary to continue collecting and analyzing data in this direction. The reliability of the test was also assessed. The reliability of the parent version scored a Cronbach’s alpha of 0.91. The reliability of the children’s version showed a Cronbach’s alpha of 0.93.