Vol 76, No 2 (2026)

This review paper consists of three parts. The first part provides an overview of the literature on the role of context in the organization of goal-directed behavior. It defines context, examines cognitive maps and navigational abilities of the brain, characteristics of contextual memory, engram search pathways, and mechanisms of consolidation and reconsolidation of contextual memory. The second part provides a brief overview of the literature on the role of motivation in the organization of goal-directed activity. This part examines the main neurophysiological theories of motivational behavior: the hypothesis of drive reduction and induction, the role of instrumental movements in motivational behavior, the hypothesis of incentive motivation, the hedonic hypothesis, and others. The third (theoretical) part examines possible mechanisms of interaction between context and motivation from the standpoint of our concept of the functional system of goal-directed behavioral control. The concept explains the formation and significance of context and motivation, and their interaction in the consolidation and retrieval of memory engrams. It is suggested that motivational excitation selectively embraces those neurons that are involved in the structure of the activated memory engram and does not concern those that are not activated. In the process of the formation and plastic rearrangement of the memory engram, not only are the maps of the environment formed, but also specialized “motivational keys” or codes for decoding these maps linked to them. In the process of memory consolidation, “motivational keys” activate the environmental maps and facilitate the formation of associative links between the elements of the engram. Thus, when forming a memory engram, specific neural networks are selectively activated in which the maps of the environment and “motivational keys” to them overlap and function as a single complex. When retrieving an engram, motivational excitation scans the memory and searches for the engram (or engrams) that correspond to the desired environment, where training was initially conducted, and a conditioned connection was developed. In order for this engram to be activated, it is necessary that in its neural network there is a coincidence of the “motivational key” with the arrival of the corresponding environmental information.

The mechanisms of occurrence, existence and functioning of receptor clusters formed on the surface of nerve cells are considered. Both experimental data and model concepts describing and explaining these processes are presented. The role of cholesterol, extracellular proteins and perimembrane cytoskeleton in formation and maintenance of the structure of receptor clusters is discussed. For ionotropic glutamate and acetylcholine receptors, the possibility of increasing the sensitivity of neurons to mediators due to cooperative activation is considered, when closely located receptors and channels of one cluster influence each other’s activity.

The aim of the work was to identify features of the myographic signal in post-stroke patients, manifesting at rest and during motor imagery (MI). In patients, an electromyogram (EMG) was recorded concurrently with EEG over the elbow flexor projection of the right and left arms. The following parameters were assessed: EMG amplitude and the directed transfer function (DTF), characterizing the strength of corticomuscular connections. The experimental protocol included 3 conditions: Rest; Imagined opening of the left hand (MI-L); and Imagined opening of the right hand (MI-R). Corticomuscular coherence in patients was maximal in the low-frequency ranges under all conditions. In the paretic arm, both EMG amplitude and DTF were higher both at rest and during MI. Afferent connections (from muscles to cortex) in the paretic limb predominated over efferent connections (from cortex to muscles). When transitioning from rest to MI, the DTF between the cortex and muscles of the paretic arm increased. During the course of therapy the strength of efferent and afferent connections significantly increased; the EMG amplitude showed a tendency to decrease.

The Stroop test is one of the most frequently used task paradigms for studying cognitive control functions in humans. Previous studies have shown that the Stroop effect is caused by interference at both the sensory and response selection levels, but it remains unclear how each type of conflict affects the ERP waves recorded during the test. In this paper, we investigated the relationship between the P300, N450, and late positive complex (LPC) waves and different types of conflict. We analyzed 31-channel ERP data from 41 healthy subjects aged 18-55 years during the classic and reverse Stroop tests, separating the types of interference. The results indicate that the P300 wave reflects conflict at the motor response level in both tests, the N450 wave reflects sensory and general conflicts in the classic test and general conflict in the reverse test and the LPC wave is associated with general conflict in the classic test and all types of conflict in the reverse test.