Reorganization of the Neurobiology of Language After Sentence Overlearning.

It is assumed that there are a static set of "language regions" in the brain. Yet, language comprehension engages regions well beyond these, and patients regularly produce familiar "formulaic" expressions when language regions are severely damaged. These suggest that the neurobiology of language is not fixed but varies with experiences, like the extent of word sequence learning. We hypothesized that perceiving overlearned sentences is supported by speech production and not putative language regions. Participants underwent 2 sessions of behavioral testing and functional magnetic resonance imaging (fMRI). During the intervening 15 days, they repeated 2 sentences 30 times each, twice a day. In both fMRI sessions, they "passively" listened to those sentences, novel sentences, and produced sentences. Behaviorally, evidence for overlearning included a 2.1-s decrease in reaction times to predict the final word in overlearned sentences. This corresponded to the recruitment of sensorimotor regions involved in sentence production, inactivation of temporal and inferior frontal regions involved in novel sentence listening, and a 45% change in global network organization. Thus, there was a profound whole-brain reorganization following sentence overlearning, out of "language" and into sensorimotor regions. The latter are generally preserved in aphasia and Alzheimer's disease, perhaps explaining residual abilities with formulaic expressions in both.

Suppression of overlearning in independent component analysis used for removal of muscular artifacts from electroencephalographic records.

This paper addresses the overlearning problem in the independent component analysis (ICA) used for the removal of muscular artifacts from electroencephalographic (EEG) records. We note that for short EEG records with high number of channels the ICA fails to separate artifact-free EEG and muscular artifacts, which has been previously attributed to the phenomenon called overlearning. We address this problem by projecting an EEG record into several subspaces with a lower dimension, and perform the ICA on each subspace separately. Due to a reduced dimension of the subspaces, the overlearning is suppressed, and muscular artifacts are better separated. Once the muscular artifacts are removed, the signals in the individual subspaces are combined to provide an artifact free EEG record. We show that for short signals and high number of EEG channels our approach outperforms the currently available ICA based algorithms for muscular artifact removal. The proposed technique can efficiently suppress ICA overlearning for short signal segments of high density EEG signals.

Overlearning hyperstabilizes a skill by rapidly making neurochemical processing inhibitory-dominant.

Overlearning refers to the continued training of a skill after performance improvement has plateaued. Whether overlearning is beneficial is a question in our daily lives that has never been clearly answered. Here we report a new important role: overlearning in humans abruptly changes neurochemical processing, to hyperstabilize and protect trained perceptual learning from subsequent new learning. Usually, learning immediately after training is so unstable that it can be disrupted by subsequent new learning until after passive stabilization occurs hours later. However, overlearning so rapidly and strongly stabilizes the learning state that it not only becomes resilient against, but also disrupts, subsequent new learning. Such hyperstabilization is associated with an abrupt shift from glutamate-dominant excitatory to GABA-dominant inhibitory processing in early visual areas. Hyperstabilization contrasts with passive and slower stabilization, which is associated with a mere reduction of excitatory dominance to baseline levels. Using hyperstabilization may lead to efficient learning paradigms.

Indivíduos Paraplégicos e o Significado Construído para a Lesão Medular em suas Vidas / Paraplegic Individuals and the Meaning-Making Process of the Spinal Cord Injury in their Lives / Individuos Parapléjicos y el Significado Construido para la Lesión Medular en sus Vidas

Resumo A aquisição de uma deficiência física implica múltiplas perdas, gerando um processo de luto e de construção de significado para a experiência vivida, além da necessidade de rever o mundo presumido e o direcionamento da vida. O objetivo deste artigo é discutir os significados construídos para a lesão medular traumática em quatro indivíduos paraplégicos, de 18 a 22 anos, assim como o processo de retomada do projeto de vida após a deficiência física. A pesquisa adotou a abordagem qualitativa, por meio de entrevista semiestruturada e utilizou a análise de conteúdo para o tratamento das informações. Percebeu-se que os significados construídos para o acometimento da lesão medular foram positivos, denotando valorização, superação, aprendizado, descoberta e transformação. Os participantes identificaram situações positivas mesmo em meio a muitas adversidades enfrentadas. Tais significados contribuíram no direcionamento dado ao novo projeto de vida, o qual precisou adequar-se à nova realidade, na condição de paraplégicos. Evidenciou-se, ainda, a importância da reabilitação física e da família como rede de suporte, a necessidade da validação desse luto, o que favorece a elaboração, contribuindo para reorganizar a vida e reinvestir nos planos futuros....(AU)

Abstract The acquisition of a physical disability involves multiple losses, leading to both a grief process and a meaning-making process of the lived experience, besides a need to review the assumptive world and the life’s direction. The purpose of this article is to present a study with four paraplegic individuals, 18-22 years old, their constructions of meaning of a traumatic spinal cord injury and the process of life resumption after the disability. This research adopted a qualitative approach, through semi-structured interviews, and content analysis for the treatment of information. It was noticed that the meanings built from the injury were positive, designating appreciation, overcoming, learning, discovering and transformation. The participants identified positive situations, even when they were facing many adversities. Such meanings contributed to the establishment of new life projects, which were adapted to a new reality of paraplegic condition. The importance of the physical rehabilitation and of the family as a support network, and the need of validating the grief (which favors its development, contributing to reorganize the life and reinvest in future plans) were also evident....(AU)

Resumen La adquisición de una incapacidad física implica múltiples pérdidas, lo que resulta en un proceso de luto y en la construcción de significado para la experiencia vivida, además de la necesidad de revisar el mundo planeado y el rumbo de la vida. Este artículo tiene como objetivo presentar un estudio con cuatro personas parapléjicas, de 18 a 22 años de edad, sobre los significados construidos para la lesión medular traumática, y el proceso de reanudación de su proyecto de vida después de la incapacidad física. La investigación adoptó un enfoque cualitativo, por medio de entrevista semiestructurada, y utilizó el análisis de contenido para el tratamiento de las informaciones. Se observó que los significados construidos para el traumatismo de la médula espinal fueron positivos, denotando valoración, superación, aprendizaje, descubrimiento y transformación. Los participantes identificaron situaciones positivas en medio de muchas adversidades que enfrentaban. Tales significados contribuyeron a dar un nuevo rumbo al proyecto de vida, que tuvo que adaptarse a la realidad actual, en la condición de paraplejia. Se mostró, también, la importancia de la rehabilitación física y de la familia como red de apoyo, la necesidad de validación del luto, lo que favorece la elaboración, contribuyendo para reorganizar la vida y reinvertir en planes futuros....(AU)

Leveraging the test effect to improve maintenance of the gains achieved through cognitive rehabilitation.

OBJECTIVE: An important aspect of the rehabilitation of cognitive and linguistic function subsequent to brain injury is the maintenance of learning beyond the time of initial treatment. Such maintenance is often not satisfactorily achieved. Additional practice, or overtraining, may play a key role in long-term maintenance. In particular, the literature on learning in cognitively intact persons has suggested that it is testing, and not studying, that contributes to maintenance of learning. The present study investigates the hypothesis that continuing to test relearned words in persons with anomia will lead to significantly greater maintenance compared with continuing to study relearned words. METHOD: The current study combines overtraining with the variable of test versus study in examining the effects of overtesting and overstudying on maintenance of word finding in 3 persons with aphasia. First, treatment successfully reestablished the connections between known items and their names. Once the connections were reestablished (i.e., items could be named successfully), each item was placed into 1 of 4 overtraining conditions: test and study, only test, only study, or no longer test or study. Maintenance was probed at 1 month and 4 months following the end of overtraining. RESULTS: The results are consistent with an advantage of testing compared with studying. All 3 participants showed significantly greater maintenance for words that were overtested than for words that were overstudied. This testing benefit persisted at 1 month and 4 months after completion of the treatment. In fact, there was no clear evidence for any benefit of overstudying. CONCLUSIONS: The present study demonstrates that overtesting, but not overstudying, leads to lasting maintenance of language rehabilitation gains in patients with anomia. The implications for the design of other treatment protocols are immense. (PsycINFO Database Record

Anchors aweigh: The impact of overlearning on entrenchment effects in statistical learning.

Previous research has revealed that when learners encounter multiple artificial languages in succession only the first is learned, unless there are contextual cues correlating with the change in structure or if exposure to the second language is protracted. These experiments provided a fixed amount of exposure irrespective of when learning occurred. Here, the authors presented learners with 2 consecutive artificial languages testing learning after each minute of familiarization. In Experiment 1, learners received fixed input, and the authors replicated the primacy effect. In Experiment 2, learners advanced to the second language immediately following robust learning of the first language (thereby limiting additional exposure past the point of learning). Remarkably, learners tended to acquire and retain both languages, although contextual cues did not boost performance further. Notably, there was no correlation between performance on this task and a flanker task that measured inhibitory control. Overall, the findings suggest that anchoring effects in statistical learning may be because of overlearning. We speculate that learners may reduce their attention to the input once they achieve a low level of estimation uncertainty. (PsycINFO Database Record

NO-FEAR Airlines: A Computer-aided Self-help Treatment for Flying Phobia.

In vivo exposure is the treatment of choice for specific phobias. However, this treatment is linked to a number of limitations in its implementation. Therefore, it is important to develop strategies for improving treatment adherence, acceptance, and dissemination of evidence-based treatments. Information and Communication Technologies, specifically, computerized programs boast advantages in treating flying phobia. NO-FEAR Airlines is a Computer-aided Self-help Treatment for this problem, which can be self-applied via Internet. NO-FEAR Airlines treatment protocol comprises three therapeutic components: psychoeducation, exposure and overlearning. Exposure is carried out through 6 scenarios that are composed by images and real sounds related to a flight in process. The aim of the present work is to describe NO-FEAR Airlines program.

Effectiveness of an alarm intervention with overlearning for primary nocturnal enuresis.

OBJECTIVE: To explore the effectiveness of the enuresis alarm with overlearning for treatment of primary nocturnal enuresis (PNE). A key objective was to explore the effect of overlearning on treatment gains, and its impact on relapse. PATIENTS AND METHODS: The RMIT University Psychology Clinic has been treating PNE in the community for more than 20 years following a standardized treatment protocol. The study analysed archival data of 126 participants, aged ≥ 5 years, presenting with PNE. A mean wetting frequency of 5.13 wet nights per week was observed at baseline. RESULTS: Treatment significantly reduced mean wetting from baseline levels during both treatment and overlearning phases, F(1.41, 176.10) = 588.54, p < 0.001, r(2) = 0.77, 95% CI (0.74-0.81). Wet nights per week reduced from a mean of 5.13 (SD = 1.77) during baseline to 1.88 (SD = 0.85) during treatment, and 0.64 (SD = 0.60) during overlearning. Alarm treatment with overlearning produced a treatment response of 87%, compared with 59% for alarm treatment only. CONCLUSIONS: Evidence of improved treatment response with the addition of overlearning suggests overlearning should be considered as a potentially useful adjunct to alarm treatment for PNE. Overlearning was not unreasonably onerous for participants. Further research is required to explore the impact overlearning has on reducing relapse rates.

A secondary working memory challenge preserves primary place strategies despite overtraining.

Learning by repetition engages distinct cognitive strategies whose contributions are adjusted with experience. Early in learning, performance relies upon flexible, attentive strategies. With extended practice, inflexible, automatic strategies emerge. This transition is thought fundamental to habit formation and applies to human and animal cognition. In the context of spatial navigation, place strategies are flexible, typically employed early in training, and rely on the spatial arrangement of landmarks to locate a goal. Response strategies are inflexible, become dominant after overtraining, and utilize fixed motor sequences. Although these strategies can operate independently, they have also been shown to interact. However, since previous work has focused on single-choice learning, if and how these strategies interact across sequential choices remains unclear. To test strategy interactions across sequential choices, we utilized various two-choice spatial navigation tasks administered on the Opposing Ts maze, an apparatus for rodents that permits experimental control over strategy recruitment. We found that when a second choice required spatial working memory, the transition to response navigation on the first choice was blocked. Control experiments specified this effect to the cognitive aspects of the secondary task. In addition, response navigation, once established on a single choice, was not reversed by subsequent introduction of a secondary choice reliant on spatial working memory. These results demonstrate that performance strategies interact across choices, highlighting the sensitivity of strategy use to the cognitive demands of subsequent actions, an influence from which overtrained rigid actions may be protected.

Effects of overtraining on extinction in newts (Cynops pyrrhogaster).

The overtraining extinction effect (OEE), a phenomenon in which extended training facilitates extinction, has been found in mammals and reptiles. However, fish have never shown OEE. No study has yet investigated OEE in newts, a representative amphibian species. We tested whether newts, Cynops pyrrhogaster, show OEE in a straight-array task. All animals received five trials per day and were given a piece of dried worm during reinforced trials. They showed significant acquisition and extinction effects in reinforced and nonreinforced trials. However, we found no difference in extinction performance between a group with 25-trial acquisition and one with 75-trial acquisition, suggesting that OEE was not found in newts. OEE has generally been explained in terms of frustration-related mechanisms. Our results suggest that emotional reactions to nonreward, such as frustration, may not influence behavior in amphibians.

Competitive Memory Training for treating depression and rumination in depressed older adults: a randomized controlled trial.

Although rumination is an important mediator of depressive symptoms, there is insufficient proof that an intervention that specifically targets rumination ameliorates the clinical condition of, depressed patients. This study investigates whether a time-limited cognitive behavioral intervention (Competitive Memory Training, or COMET for depressive rumination) is an effective treatment for depression and rumination. This intervention was tested in older adult depressed outpatients. A total of 93 patients (aged ≥ 65 years with major depression and suffering from rumination) were treated in small groups according to the COMET protocol in addition to their regular treatment. Patients were randomized to two treatment conditions: 7 weeks of COMET + treatment-as-usual (TAU) versus TAU only. COMET + TAU showed a significant improvement in depression and rumination compared with TAU alone. This study shows that the transdiagnostic COMET protocol for depressive rumination might also be successful in treating depression and rumination in older adults.

Recombinative reading derived from pseudoword instruction in a miniature linguistic system.

A miniature linguistic system was used to study acquisition of recombinative symbolic behavior. Three studies evaluated the teaching conditions of conditional discriminations with printed and spoken pseudowords that could potentially generate recombinative reading. Fifty-four college students across all studies learned to match 12 printed pseudowords to 12 spoken pseudowords. Some also matched pictures to the same spoken words. Each two-syllable pseudoword was formed by symbols from an arbitrarily created alphabet composed of four vowels and four consonants. Letters had univocal correspondence with phonemes. Recombinative receptive reading, comprehensive reading, and textual responding to pseudowords were periodically assessed. Experiment 1 (n  =  20) showed that recombinative reading increased as the number of trained words composed of the same symbols increased. Experiment 2 (n  =  14) showed that overtraining the same two words did not produce recombinative reading for most participants. Experiment 3 (n  =  20), in which training with pictures was omitted, showed that elemental control by within-syllable units can develop even when the trained pseudowords are meaningless (not related to pictures). The present results support the utility of the miniature linguistic system methodology for identifying and controlling environmental determinants of rudimentary reading skills.

How do selected arrows guide visuospatial attention? Dissociating symbolic value and spatial proximity.

Previous research on the control of visuospatial attention showed that overlearned symbols like arrows have the potential to induce involuntary shifts of attention. Following work on the role of attentional control settings and of the content of working memory in the involuntary deployment of visuospatial attention, Pratt and Hommel (2003) found that this unintentional orienting by an arrow depended on its top-down selection, contingent on the attentional control settings, that is to say, the target selection cue. However, in this study, each arrow was closer to the location it indicated than to any other location, raising the issue of attention being drawn to the arrow location, facilitating processing at adjacent locations, rather than pushed to the symbolically cued location. In the present study, we dissociated symbolic cueing and spatial proximity cueing by the selected arrow. The results support the proximity cueing hypothesis.

Perceived tiredness and heart rate variability in relation to overload during a field hockey World Cup.

The aim of the study was to examine the utility of perceived tiredness to predict cardiac autonomic response to overload among field hockey players during the 2006 World Cup. The French Society for Sports Medicine (SFMS) questionnaire was administered at the start of the Cup to evaluate perception of tiredness. Autonomic function was assessed nine days later at the semifinal match by time and frequency domain analysis of heart rate variability. An anxiety questionnaire was administered so that the effect of precompetitive anxiety on heart rate variability could be controlled. Results showed a negative correlation between perceived tiredness scores and time domain indexes, and a positive correlation of perceived tiredness scores and the high frequency component ratio (LF/HF ratio) of heart rate variability. Anxiety did not influence the precompetitive cardiac response despite somatic anxiety's correlation with sympathetic response (LF/HF ratio) and tiredness scores. Perceived tiredness predicted the autonomic cardiac response to competitive overload. Thus, the perceived tiredness assessment would be a good early marker of fatigue and overload states during competition.

Episodic contributions to sequential control: learning from a typist's touch.

Sequential control over routine action is widely assumed to be controlled by stable, highly practiced representations. Our findings demonstrate that the processes controlling routine actions in the domain of skilled typing can be flexibly manipulated by memory processes coding recent experience with typing particular words and letters. In two experiments, we extended Masson's (1986) procedure for measuring item-specific learning in the context of acquiring an unfamiliar skill to the highly skilled domain of typing. Skilled typists' performance improved during practice with typing words composed from a specific set of letters. In a transfer phase, performance was fastest for trained words, followed by new words composed of trained letters, and slowest for new words composed of untrained letters. The finding that recent episodic experience with typing particular words and letters influences skilled typing performance holds widespread implications for theories of typing, sequence learning, and motor control.

Association between learning capabilities and practice-related activation changes in schizophrenia.

The present functional magnetic resonance imaging study investigated the neural correlates of practice-associated activation changes in patients with schizophrenia and their association with symptom severity. A group of patients (n = 24) were divided into more successful and less successful learners and were asked to perform a verbal overlearning task in the scanner. We found that both patient groups profited from practice, showing significant decreases in mean response times as well as significant learning-related decreases in cerebral activation. Direct comparison between groups yielded a relative hyperactivation in the group of the less successful learners at the beginning of practice, which showed a reduction with increasing practice. This was reflected by relatively stronger signal decreases in a predominantly fronto-parieto-cerebellar network. In the group of less successful learners, there was a negative correlation between general symptom scores and learning-related signal decreases in a task-relevant network involving cerebellar, inferior and middle frontal (BA 45/47, 46), superior parietal (BA 31), and superior temporal (BA 39) regions. Present data indicate that hyperactivity under high task demands might serve to identify those patients with less potential to profit from practice. However, at least in the context of moderate- to low-working memory demands, this activation abnormality seems to constitute a state rather than a trait characteristic, which patients manage to reduce by successful short-term learning. The findings also suggest that successful learners can better compensate potentially interfering effects exerted by disorder-related psychopathology.

Orienting of attention with eye and arrow cues and the effect of overtraining.

In contrast to the classical distinction between a controlled orienting of attention induced by central cues and an automatic capture induced by peripheral cues, recent studies suggest that central cues, such as eyes and arrows, may trigger a reflexive-like attentional shift. Yet, it is not clear if the attention shifts induced by these two cues are similar or if they differ in some important aspect. To answer this question, in Experiment 1 we directly compared eye and arrow cues in a counter-predictive paradigm while in Experiment 2 we compared the above cues with a different symbolic cue. Finally, in Experiment 3 we tested the role of over-learned associations in cueing effects. The results provide evidence that eyes and arrows induce identical behavioural effects. Moreover, they show that over-learned associations between spatially neutral symbols and the cued location play an important role in yielding early attentional effects.

Confabulation in healthy aging is related to interference of overlearned, semantically similar information on episodic memory recall.

Normal aging is characterized by reduced performance on tasks of long-term memory. Older adults (OA) not only show reduced performance on tasks of recall and recognition memory, but also, compared to young adults (YA), are more vulnerable to memory distortions. In this study we describe the performance of a group of OA and a group of YA on the recall of three different types of story: a previously unknown story, a well-known fairy tale (Sleeping Beauty), and a modified well-known fairy tale (Little Red Riding Hood is not eaten by the wolf). The aim of our study was to test the hypothesis that in OA strongly represented, overlearned information interferes with episodic recall-that is, the retrieval of specific, unique past episodes. OA produced significantly more confabulations than YA and in particular in the recall of the modified fairy tale. Our findings indicate that the interference of strongly represented, overlearned information in episodic memory recall is implicated in the production of confabulations in OA. This effect is particularly prominent when the to-be remembered episodic information shows strong semantic similarities with preexisting, overlearned information.

The objectification of overlearned sequences: a new view of spatial sequence synesthesia.

In the phenomenon of spatial sequence synesthesia (SSS), subjects can articulate explicit spatial locations for sequences such as numbers, letters, weekdays, months, years, and other overlearned series. Similarly, abstract sequences can take on implicit spatial representations in non-synesthetes, as evidenced by the spatial numerical association of response codes (SNARC) effect. An open question is whether the two findings represent different degrees of the same condition, or different conditions. To address this, we developed computer programs to quantify three-dimensional (3D) month-form coordinates in 571 self-reported spatial sequence synesthetes; this approach opens the door for the first time to quantified large-scale analysis. First, despite the common assumption that month-forms tend to be elliptical, we find this to be true in only a minority of cases. Second, we find that 27% of month forms are in the shape of lines, consistent with the assumed shape of implicit spatial forms in the SNARC effect. Next, we find that the majority of month forms are biased in a left-to-right direction, also consistent with the directional bias in the SNARC effect (in Western speakers). Collectively, these findings support the possibility that SSS is directly related to the sequence representations in non-synesthetes. While the search for neural correlates has concentrated on areas in the parietal lobe involved in numeric manipulation and coordinate systems, we propose that the basis of this synesthesia may be the close proximity of temporal lobe regions implicated in sequence coding and visual object representation.

Contrasting the overexpectation and extinction effects.

After many target stimulus (X)-unconditioned stimulus (US) pairings, further conditioning of X in the presence of another well-established signal for the US (A) disrupts X's behavioral control. Some researchers have argued that the mechanism underlying this so-called overexpectation effect is similar to that underlying extinction (a reduction in X's behavioral control due to X-alone presentations). Three conditioned suppression experiments with rats as subjects compared overexpectation and extinction. Experiment 1 replicated the basic overexpectation effect by showing that A disrupts responding to X more than does a previously neutral stimulus. Experiment 2 found that posttraining context exposure disrupts extinction but not overexpectation. Experiment 3 suggested that overexpectation and extinction are differentially sensitive to the effects of overtraining (compound reinforced or nonreinforced, respectively), such that extinction is enhanced by increases in the amount of nonreinforced trials and overexpectation is unaffected. These results are inconsistent with the view that overexpectation and extinction are driven by a common mechanism.