Networks in the mind – what communities reveal about the structure of the lexicon

The mental lexicon stores words and information about words. The lexicon is seen by many researchers as a network, where lexical units are nodes and the different links between the units are connections. Based on the analysis of a word association network, in this article we show that different kinds of associative connections exist in the mental lexicon. Our analysis is based on a word association database from the agglutinative language Hungarian. We use communities – closely knit groups – of the lexicon to provide evidence for the existence and coexistence of different connections. We search for communities in the database using two different algorithms, enabling us to see the overlapping (a word belongs to multiple communities) and non-overlapping (a word belongs to only one community) community structures. Our results show that the network of the lexicon is organized by semantic, phonetic, syntactic and grammatical connections, but encyclopedic knowledge and individual experiences are also shaping the associative structure. We also show that words may be connected not just by one, but more types of connections at the same time.

ASSOCIATIVE BEHAVIOR OF MEDICAL STUDENTS IN THE EXPERIMENTAL RESEARCH OF MEDICAL TERMS

Статья представляет собой изложение результатов предварительного эксперимента, связанного с изучением динамических аспектов ассоциативной структуры значения медицинских терминов в индивидуальном сознании студентов медицинского вуза с разной степенью сформированности профессиональных компетенций. Проведенный анализ данных психолингвистического эксперимента позволяет обнаружить закономерности в изменении ассоциативного пространства терминологической единицы в строящемся профессиональном сознании будущего медика. The article shows the results of the preliminary experiment connected to the study of dynamic aspects of the associative structure of medical terms’ meaning in the individual consciousness of medical students with different degree of professional competence. Complex usage of the experiment’s data reveals the regularity in changing of the associative space of a term in the forming professional consciousness of a future doctor.

Variation of connectivity across exemplar sensory and associative thalamocortical loops in the mouse

The thalamus engages in sensation, action, and cognition, but the structure underlying these functions is poorly understood. Thalamic innervation of associative cortex targets several interneuron types, modulating dynamics and influencing plasticity. Is this structure-function relationship distinct from that of sensory thalamocortical systems? Here, we systematically compared function and structure across a sensory and an associative thalamocortical loop in the mouse. Enhancing excitability of mediodorsal thalamus, an associative structure, resulted in prefrontal activity dominated by inhibition. Equivalent enhancement of medial geniculate excitability robustly drove auditory cortical excitation. Structurally, geniculate axons innervated excitatory cortical targets in a preferential manner and with larger synaptic terminals, providing a putative explanation for functional divergence. The two thalamic circuits also had distinct input patterns, with mediodorsal thalamus receiving innervation from a diverse set of cortical areas. Altogether, our findings contribute to the emerging view of functional diversity across thalamic microcircuits and its structural basis.

Responding to preconditioned cues is devaluation sensitive and requires orbitofrontal cortex during cue-cue learning

The orbitofrontal cortex (OFC) is necessary for inferring value in tests of model-based reasoning, including in sensory preconditioning. This involvement could be accounted for by representation of value or by representation of broader associative structure. We recently reported neural correlates of such broader associative structure in OFC during the initial phase of sensory preconditioning (Sadacca et al., 2018). Here, we used optogenetic inhibition of OFC to test whether these correlates might be necessary for value inference during later probe testing. We found that inhibition of OFC during cue-cue learning abolished value inference during the probe test, inference subsequently shown in control rats to be sensitive to devaluation of the expected reward. These results demonstrate that OFC must be online during cue-cue learning, consistent with the argument that the correlates previously observed are not simply downstream readouts of sensory processing and instead contribute to building the associative model supporting later behavior.

Devaluation-sensitive responding to preconditioned cues requires orbitofrontal cortex during initial cue-cue learning

The orbitofrontal cortex (OFC) is necessary for value inference in tests of model-based reasoning. This ability could be accounted for by either representation of value or by representation of broader associative structure. Our lab recently reported correlates of both value and of valueless associative structure in OFC using single-unit recording (Sadacca et al., 2018). This incidental stimulus-stimulus representation was surprising since OFC was thought to be involved only when items of biological significance were driving responses. However, we did not assess whether this activity was necessary for encoding the associative information that would contribute to value inference during probe testing. Here, we used optogenetic OFC inhibition during sensory preconditioning to test this. We found that OFC inhibition during preconditioning impaired value inference during the probe test, demonstrating that the correlates we previously observed are not simply downstream readouts of sensory processing and instead contribute to encoding valueless sensory associative information.

Some Innovative Types of Fuzzy Ideals in AG-Groupoids

AG-groupoids (non-associative structure) are basic structures in Flocks theory. This theory mainly focuses on distance optimization, motion replication, and leadership maintenance with a wide range of applications in physics and biology. In this paper, we define some new types of fuzzy ideals of AG-groupoids called (α, β)-fuzzy bi-ideals, (α, β)-fuzzy interior ideals, (β̄, ᾱ)-fuzzy bi-ideals, and (β̄, ᾱ)-fuzzy interior ideals, where α, β∈{∈γ, qδ, ∈γ∨qδ, ∈γ∧qδ} and ᾱ, β̄∈{⋶γ, q̄δ, ⋶γ∨q̄δ, ⋶γ∧q̄δ}, with α≠∈γ∧qδ and β̄≠⋶γ∧q̄δ. An important milestone achieved by this paper is providing the connection between classical algebraic structures (ordinary bi-ideals, interior ideals) and new types of fuzzy algebraic structures [(∈γ, ∈γ∨qδ)-fuzzy bi-ideals, (∈γ, ∈γ∨qδ)-fuzzy interior ideals]. Special attention is given to (∈γ, ∈γ∨qδ)-fuzzy bi-ideals and (⋶γ, ⋶γ∨q̄δ) -fuzzy bi-ideals.

Perceptual Generalization and Context in a Network Memory Inspired Long-Term Memory for Artificial Cognition

In the framework of open-ended learning cognitive architectures for robots, this paper deals with the design of a Long-Term Memory (LTM) structure that can accommodate the progressive acquisition of experience-based decision capabilities, or what different authors call “automation” of what is learnt, as a complementary system to more common prospective functions. The LTM proposed here provides for a relational storage of knowledge nuggets given the form of artificial neural networks (ANNs) that is representative of the contexts in which they are relevant in a configural associative structure. It also addresses the problem of continuous perceptual spaces and the task- and context-related generalization or categorization of perceptions in an autonomous manner within the embodied sensorimotor apparatus of the robot. These issues are analyzed and a solution is proposed through the introduction of two new types of knowledge nuggets: P-nodes representing perceptual classes and C-nodes representing contexts. The approach is studied and its performance evaluated through its implementation and application to a real robotic experiment.

Psychosemantic Features of Professional Consciousness of Engineers

This article presents results of an empiric study of psychosemantic features of professional consciousness of engineers: the associative structure of key professional notions has been determined, and its key properties have been revealed. The method of free associations has been applied; J. Sax’s and S. Levis’s Unfinished Sentences projective technique; original questionnaire. It was proved that engineers are distinguishable for the desire to get promoted to a higher position while retaining inclination toward the present area of activity; functional autonomy; dependence on organization; internal control locus in the situation of professional problems; long-term professional planning; orientation toward refraining from inflicting damages upon others and themselves; balanced moral principles. An associative experiment has been held with stimuli words that concern professional sphere and with words unrelated to the profession. 1524 reactions to 37 stimuli words have been received in total. Building associative complexes for every stimulating notion allowed to reflect contemporary perceptions of respondents about each of them. The following most frequently occurring associations to the “work” stimulus have been highlighted: knowledge, experience, skills, work routine, Monday-Friday, boss, half-life, prospects, growth, success, hard. One of the features of professional consciousness of engineers is fixation of own subordination in performance of professional duties; inclination toward timely accomplishment of simple professional tasks; orientation of mindset toward integrity and discipline in business communication.