Explicit encoding vs. fast mapping of novel spoken words: Electrophysiological and behavioural evidence of diverging mechanisms.

It has been claimed that two major neurocognitive mechanisms - instruction-based explicit encoding (EE) and inference-driven fast mapping (FM) may be involved in rapid acquisition of novel words, but their exact neural underpinnings remain poorly understood. To address this, we trained 36 adult participants with 20 novel spoken words in an audio-visual task, carefully balanced between the EE and FM conditions for physical, psycholinguistic and pragmatic properties as well as the overall task setup. To assess the neural dynamics associated with novel word acquisition, we recorded event-related potentials (ERPs) elicited by these words before and after training, and analysed their relationship with the behavioural learning outcomes, measured in a semantic matching task. Both learning regimes led to successful acquisition, which was somewhat more efficient for EE than FM, as indicated by higher accuracy in the behavioural task. We also found that, whereas words learnt via both EE and FM protocols elicited most pronounced ERP peaks at ∼196 and ∼280 ms, these two phases of activity diverged with respect to the learning type. Multiple linear regression and correlation analyses indicated that the learning-induced amplitude dynamics in the earlier peak was significantly related to behavioural performance for FM-learned items, which may possibly be explained by FM's stronger reliance on early automatic mechanisms of word processing. Performance on EE words was, in turn, significantly linked to the amplitude of the second peak only, potentially due to the involvement of later, top-down controlled processes in this type of word acquisition. Grand-average ERP-based source analysis indicated a left-lateralised activity in the anterior-temporal lobe for FM learning, and a bilateral activation for EE. The results confirm the existence of partially diverging neurocognitive systems for word acquisition and suggest that the configuration of newly established word memory circuits depends on the mode of their acquisition.

Anodal tDCS over Broca's area improves fast mapping and explicit encoding of novel vocabulary.

An accumulating body of evidence suggests that transcranial direct current stimulation (tDCS) can be used to affect language processing, including word acquisition. There has been, however, no comprehensive study of effects of tDCS of the core language areas in relation to the main word-learning mechanisms. Two principal strategies have been posited as important for natural word acquisition: explicit encoding (EE) which relies on direct instructions and repetition of material, and fast mapping (FM) which operates implicitly, via context-based inference or deduction. We used anodal and cathodal tDCS of Broca's and Wernicke's areas to assess effects of stimulation site and polarity on novel word acquisition in both EE and FM regimes. 160 participants, divided into five groups, received 15 min of cathodal or anodal tDCS over one of the two areas or a sham (placebo) stimulation before learning eight novel words, presented ten times each in a short naturalistic audio-visual word-picture association session, fully counterbalanced across different learning regimes. The outcome of novel word acquisition was measured immediately after the training using a free recall task. The results showed elevated accuracy in all real stimulation groups in comparison with sham stimulation; however, this effect only reached full significance after anodal tDCS of Broca's area. Comparisons between the two learning modes indicated that Broca's anodal tDCS significantly improved both implicit and explicit acquisition of novel vocabulary in comparison with sham tDCS, without, however, any significant differences between EE and FM regimes as such. The results indicate involvement of the left inferior-frontal neocortex in the learning of novel vocabulary and suggest a possibility to promote different types of word acquisition using anodal tDCS of this area.

Comprehensive Molecular Genetic Diagnostics of Birt-Hogg-Dube Syndrome in a Russian Patient with Renal Cancer and Lung Cysts: A Case Report.

We report a case of Birt-Hogg-Dube syndrome (BHDS), a rare hereditary syndrome, the main visible sign of which is the development of multiple skin fibrofolliculomas. In our case, there was a manifestation of BHDS consisting in the absence of fibrofolliculomas and presence of other characteristic features of this syndrome: lung cysts and renal cancer. The 26-year-old woman was admitted to a clinic for diagnosis and treatment of a neoplasm of the left kidney and had a history of renal cell cancer (RCC) of the right kidney and spontaneous pneumothorax. Multiple tumors of the left kidney and lung cysts were observed upon clinical and laboratory testing. Tumors of the left kidney were resected and diagnosed by a pathologist as chromophobe RCC. Sequencing of FLCN exons 4-14 from blood DNA revealed the heterozygous germline nonsense mutation c.1429C>T (p.R477*), confirming the diagnosis of BHDS. Several somatic variants were detected by tumor DNA sequencing using the Comprehensive Cancer Panel and Ion S5 platform. Medical-genetic counseling was conducted, and follow-up management was outlined. To our knowledge, this case report is the first comprehensive clinical and genetic examination of a patient with BHDS in Russia. The p.R477* mutation has been described by other authors in patients with fibrofolliculomas and lung cysts, but not in those with RCC, while RCC was the first manifestation of BHDS in our case. The case report may help geneticists, oncologists, and other specialists to better understand the clinical and genetic heterogeneity of BHDS in various populations.

Electrophysiological Evidence of Dissociation Between Explicit Encoding and Fast Mapping of Novel Spoken Words.

Existing behavioral, neuropsychological and functional neuroimaging data suggest that at least two major cognitive strategies are used for new word learning: fast mapping (FM) via context-dependent inference and explicit encoding (EE) via direct instruction. However, these distinctions remain debated at both behavioral and neurophysiological levels, not least due to confounds related to diverging experimental settings. Furthermore, the neural dynamics underpinning these two putative processes remain poorly understood. To tackle this, we designed a paradigm presenting 20 new spoken words in association with pictures in either FM or EE settings, closely matched for auditory and visual features and overall task demands. We tested word acquisition using a range of behavioral measures as well as passive event-related potential (ERP) responses, an established measure of word memory trace activation, and compared brain activity elicited by novel FM and EE words before and after the learning session. Behavioral data obtained in free recall, recognition and semantic word-picture matching tasks indicated successful acquisition of new words after just 10 exposures. Crucially, we found no behavioral evidence of different acquisition outcomes between FM and EE learning. ERP data, which exhibited the main response peaks at ~170, 250, and 520 ms, also indicated successful learning, with statistically different responses between novel and familiar words present only before, but not after the training, suggesting rapid formation of new neural memory circuits matching in activation those for previously known words. Furthermore, already at the earliest peak, we found different topographic distributions for the two learning types, with left-lateralized FM dynamics, suggestive of core language system involvement, and more diffuse activity for EE items, possibly suggesting the role of attention/executive control network. A similar effect also manifested later, at ~520 ms. Our data suggest that while both EE and FM learning can be successful for rapid word acquisition at the behavioral level, the diverging electrophysiological patterns suggest a dissociation between the neural systems underpinning these learning strategies.

A different kind of pain: affective valence of errors and incongruence.

People hiss and swear when they make errors, frown and swear again when they encounter conflicting information. Such error- and conflict-related signs of negative affect are found even when there is no time pressure or external reward and the task itself is very simple. Previous studies, however, provide inconsistent evidence regarding the affective consequences of resolved conflicts, that is, conflicts that resulted in correct responses. We tested whether response accuracy in the Eriksen flanker task will moderate the effect of trial incongruence using affective priming to measure positive and negative affect. We found that responses to incongruent trials elicit positive affect irrespective of their accuracy. Errors, in turn, result in negative affect irrespective of trial congruence. The effects of conflicts and errors do not interact and affect different dimensions of affective priming. Conflicts change the speed of evaluative categorisation while errors are reflected in categorisation accuracy. We discuss the findings in light of the "reward value and prediction" model and the "affect as a feedback for predictions" framework and consider the possible mechanisms behind the divergent effects.

Blame everyone: Error-related devaluation in Eriksen flanker task.

Preferences are determined not only by stimuli themselves but also by the way they are processed in the brain. The efficacy of cognitive processing during previous interactions with stimuli is particularly important. When observers make errors in simple tasks such as visual search, recognition, or categorization, they later dislike the stimuli associated with errors. Here we test whether this error-related devaluation exists in Erisken flanker task and whether it depends on the distribution of attention. We found that both attended stimuli (targets) and ignored ones (distractors) are devaluated after errors on compatible trials but not incompatible ones. The extent of devaluation is similar for targets and distractors, indicating that distribution of attention does not significantly influence the attribution of error-related negative affect. We discuss this finding in light of the possible mechanisms of error-related devaluation.

How to tell a wife from a hat: affective feedback in perceptual categorization.

How do people understand that their perception is correct? In line with the recurring idea of perception as prediction, the affective feedback account of hypotheses testing suggests that correct perceptual predictions are reinforced with positive affect. In four experiments, we tested whether correct categorization of a degraded image will lead to more positive liking ratings. The obtained findings supported the proposed approach: subjects liked the images they were able to perceive correctly more than others. Importantly, these findings were independent of the initial affective valence of stimuli. A further investigation demonstrated that this effect exists only when answers are at least moderately confident. The obtained findings add to the growing amount of literature on the role of affect in basic cognitive processing.

Does unconscious information affect cognitive activity?: a study using experimental priming.

In a series of three experiments the influence that information unrecognised by the subjects has on the effectiveness of occurring cognitive activity is studied. With this aim 3 types of stimulus were compared which for one reason or another were not afforded sufficient attention, namely: unconscious meanings of polysemantic information, stimuli presented at the subliminal level, and intentionally ignored distractors. All the listed types of stimuli are united in that the subjects were not able to give an account of them, i.e., these stimuli were not processed attentively. It is assumed that each of the types of stimuli studied is in actuality perceived, which can be judged by the impact they have on occurring cognitive activity. The purpose of the present research is the comparison of this impact: apart from the determination of the impact of unperceived stimuli on the information directly associated with them (priming-effect registration), also identified is the presence/absence of an overall interference effect rendered by the unperceived stimuli on the performance of occurring cognitive activity. To this end, each experiment had a control condition the aim of which was the creation of the possibility for the subjects to perceive stimuli unnoticed under experimental conditions. An experimental priming paradigm was used in combination with image-classification and lexical-decision tasks. The results of the experiments conducted demonstrate that all types of stimuli 'slipping the attention' are assimilated, but their effect on occurring cognitive activity is varied. Thus, subliminally presented information aids, and distractors, on the contrary, hinder the solution of tasks associated with them, whereas unperceived meanings of polysemantic information hinder not only the solution of the tasks directly associated with them, but also the performance of any other cognitive activity for which they serve as a context. The effect of subliminal stimuli on occurring cognitive activity in the present research is explained by the spreading activation in the memory, the effect of distractors--by the inhibition of irrelevant representations in the information-processing system. For an explanation of the consequence of unperceived meanings of polysemanticity, not only an inhibition model was used, but also an unconscious negative choice model which assumed the necessity of making a special decision on non-perception.

Does unconscious information affect cognitive activity?: a study using experimental priming

In a series of three experiments the influence that information unrecognised by the subjects has on the effectiveness of occurring cognitive activity is studied. With this aim 3 types of stimulus were compared which for one reason or another were not afforded sufficient attention, namely: unconscious meanings of polysemantic information, stimuli presented at the subliminal level, and intentionally ignored distractors. All the listed types of stimuli are united in that the subjects were not able to give an account of them, i.e., these stimuli were not processed attentively. It is assumed that each of the types of stimuli studied is in actuality perceived, which can be judged by the impact they have on occurring cognitive activity. The purpose of the present research is the comparison of this impact: apart from the determination of the impact of unperceived stimuli on the information directly associated with them (priming-effect registration), also identified is the presence/absence of an overall interference effect rendered by the unperceived stimuli on the performance of occurring cognitive activity. To this end, each experiment had a control condition the aim of which was the creation of the possibility for the subjects to perceive stimuli unnoticed under experimental conditions. An experimental priming paradigm was used in combination with image-classification and lexical-decision tasks. The results of the experiments conducted demonstrate that all types of stimuli 'slipping the attention' are assimilated, but their effect on occurring cognitive activity is varied. Thus, subliminally presented information aids, and distractors, on the contrary, hinder the solution of tasks associated with them, whereas unperceived meanings of polysemantic information hinder not only the solution of the tasks directly associated with them, but also the performance of any other cognitive activity for which they serve as a context. The effect of subliminal stimuli on occurring cognitive activity in the present research is explained by the spreading activation in the memory, the effect of distractors - by the inhibition of irrelevant representations in the information-processing system. For an explanation of the consequence of unperceived meanings of polysemanticity, not only an inhibition model was used, but also an unconscious negative choice model which assumed the necessity of making a special decision on non-perception (AU)

En una serie de tres experimentos se estudió la influencia que tiene la información no reconocida por los participantes en la efectividad de la actividad cognitiva concurrente. Con este objetivo, se compararon 3 tipos de estímulos que por una razón u otra, no obtenían suficiente atención, como: significados no conscientes de información poli-semántica, estímulos presentados a nivel subliminal, y distractores ignorados intencionalmente. Todos los tipos de estímulos mencionados tienen en común que los sujetos no eran capaces de percatarse de ellos, i.e., estos estímulos no se procesaban atentamente. Se asume que cada uno de los tipos de estímulos estudiados es percibido, lo que puede juzgarse por el impacto que tienen en la actividad cognitiva concurrente. El propósito de esta investigación es la comparación de este impacto: además de la determinación del impacto de estímulos no percibidos en la información directamente asociada a ellos (registro del efecto de facilitación), también se identifica la presencia/ausencia de un efecto global de interferencia de los estímulos no percibidos en el en el desempeño de la actividad cognitiva concurrente. Hasta este punto, cada experimento tuvo una condición de control cuyo objetivo era crear la posibilidad de que los sujetos percibieran los estímulos no percatados bajo las condiciones experimentales. Se utilizó un paradigma experimental de priming en combinación con tareas de clasificación de imágenes y de decisión léxica. Los resultados de los experimentos realizados demuestran que todos los tipos de estímulos que ôescapaban a la atenciónö eran asimilados, pero su efecto en la actividad cognitiva concurrente variaba. Por tanto, la información presentada de forma subliminal facilita, y los distractores, al contrario, retrasan la solución de tareas asociadas a ellos, mientras que los significados no percibidos de la información poli semántica retrasan no sólo la solución de tareas directamente asociadas a ellos, pero también el desempeño de cualquier otra actividad cognitiva para la que sirvan como contexto. El efecto de estímulos subliminales en la actividad cognitiva concurrente de esta investigación se explica por la propagación de la activación en memoria, el efecto de los distractores -por la inhibición de representaciones irrelevantes en el sistema de procesamiento de información. Para daruna explicación de la consecuencia de significados de poli semántica no percibidos, no sólo se ha utilizado un modelo de inhibición sino también un modelo de decisión negativa inconsciente que asume la necesidad de tomar una decisión especial en no-percepción (AU)