The effect of sleep and semantic information on associative novel word learning.

This study investigated the effect of overnight sleep on associative novel word learning and examined whether the effects of sleep on word learning are modulated by the provision of semantic information. Seventy-five healthy young adults attended an initial word-learning session followed by a delayed testing session. An interval of overnight sleep (sleep group) or daytime wakefulness (wake group) separated the two sessions. At the initial learning session, participants learned three-word names of 20 novel objects, where half the names comprised a novel word and two semantic attributes (semantic condition), and half comprised a novel word and two meaningless proper names (name condition). Novel word cued-recall was measured at both the initial and the delayed session. Although both groups demonstrated similar cued-recall accuracy at the first session, by the delayed session the sleep group demonstrated superior cued-recall accuracy compared to the wake group. There was no influence of semantics on the sleep-dependent consolidation of the novel words. Overall, these findings suggest that novel words encoded with or without the provision of semantic information can benefit from an overnight sleep period for consolidation.

How Effective are Pictures in Eliciting Information from People Living with Dementia? A Systematic Review.

OBJECTIVES: Decline in language and cognitive functioning often deprives people living with moderate-to-severe dementia of self-reporting their quality of life (QoL) on the written and verbal formats of questionnaires. This systematic review aimed to evaluate the effectiveness of pictorial tools as an alternative method for enabling people living with dementia to self-report their QoL. METHODS: PubMed, PsycINFO, CINAHL, and EMBASE were searched. Primary research studies reporting on information elicitation from people living with dementia through pictures were deemed eligible. Six studies satisfied the inclusion criteria. Methodological quality of the studies was evaluated through Downs and Black checklist. Data was extracted according to population, intervention, comparator, and outcomes (PICO) and results were summarized and supplemented by narrative synthesis. RESULTS: Compared to usual communication methods, pictorial tools were found to have a superior effect on comprehension of conversations and decision-making abilities, minimal effect on preference consistency, and an undeterminable effect on discourse features. CONCLUSIONS: There is consistent evidence that pictures enhance comprehension and might facilitate decision-making abilities. CLINICAL IMPLICATIONS: QoL information can be elicited more effectively through pictorial tools. Future studies warrant development of pictorial versions of standardized QoL tools which will assist the inclusion of people living with severe dementia.

Effects of emotional cues on novel word learning in typically developing children in relation to broader autism traits.

Emotion can influence various cognitive processes. Communication with children often involves exaggerated emotional expressions and emotive language. Children with autism spectrum disorder often show a reduced tendency to attend to emotional information. Typically developing children aged 7 to 9 years who varied in their level of autism-like traits learned the nonsense word names of nine novel toys, which were presented with either happy, fearful, or neutral emotional cues. Emotional cues had no influence on word recognition or recall performance. Eye-tracking data showed differences in visual attention depending on the type of emotional cues and level of autism-like traits. The findings suggest that the influence of emotion on attention during word learning differs according to whether the children have lower or higher levels of autism-like traits, but this influence does not affect word learning outcomes.

Corticostriatal Regulation of Language Functions.

The role of corticostriatal circuits in language functions is unclear. In this review, we consider evidence from language learning, syntax, and controlled language production and comprehension tasks that implicate various corticostriatal circuits. Converging evidence from neuroimaging in healthy individuals, studies in populations with subcortical dysfunction, pharmacological studies, and brain stimulation suggests a domain-general regulatory role of corticostriatal systems in language operations. The role of corticostriatal systems in language operations identified in this review is likely to reflect a broader function of the striatum in responding to uncertainty and conflict which demands selection, sequencing, and cognitive control. We argue that this role is dynamic and varies depending on the degree and form of cognitive control required, which in turn will recruit particular corticostriatal circuits and components organised in a cognitive hierarchy.

Cross-modal emotion recognition and autism-like traits in typically developing children.

The ability to explicitly recognize emotions develops gradually throughout childhood, and children usually have greater difficulty in recognizing emotions from the voice than from the face. However, little is known about how children integrate vocal and facial cues to recognize an emotion, particularly during mid to late childhood. Furthermore, children with an autism spectrum disorder often show a reduced ability to recognize emotions, especially when integrating emotion from multiple modalities. The current preliminary study explored the ability of typically developing children aged 7-9 years to match emotional tones of voice to facial expressions and whether this ability varies according to the level of autism-like traits. Overall, children were the least accurate when matching happy and fearful voices to faces, commonly pairing happy voices with angry faces and fearful voices with sad faces. However, the level of autism-like traits was not associated with matching accuracy. These results suggest that 7- to 9-year-old children have difficulty in integrating vocal and facial emotional expressions but that differences in cross-modal emotion matching in relation to the broader autism phenotype are not evident in this task for this age group with the current sample.

Spelling in Children With Cochlear Implants: Evidence of Underlying Processing Differences.

This study compared the spelling skills and sub-skills of young children with cochlear implants (CIs) who use spoken language only (n = 14) with those of a same-aged typically hearing (TH) control group (n = 30). Spelling accuracy was assessed using irregular and nonsense word stimuli. Error and regression analyses were conducted to provide insight into the phonological and orthographic spelling strategies used by each group. Results indicated that children with CIs were as accurate as the TH group. However, misspellings made by the CI group were less phonologically plausible, and while nonword spelling accuracy was related to letter-sound knowledge for the TH group, the same relationship was non-significant for the CI group. Hence, despite demonstrating a similar degree of overall spelling success to TH children, children with CIs appeared to apply phonics skills less effectively.

A Neurophysiological Study of Semantic Processing in Parkinson's Disease.

OBJECTIVES: Cognitive-linguistic impairments in Parkinson's disease (PD) have been well documented; however, few studies have explored the neurophysiological underpinnings of semantic deficits in PD. This study investigated semantic function in PD using event-related potentials. METHODS: Eighteen people with PD and 18 healthy controls performed a semantic judgement task on written word pairs that were either congruent or incongruent. RESULTS: The mean amplitude of the N400 for new incongruent word pairs was similar for both groups, however the onset latency was delayed in the PD group. Further analysis of the data revealed that both groups demonstrated attenuation of the N400 for repeated incongruent trials, as well as attenuation of the P600 component for repeated congruent trials. CONCLUSIONS: The presence of N400 congruity and N400 repetition effects in the PD group suggests that semantic processing is generally intact, but with a slower time course as evidenced by the delayed N400. Additional research will be required to determine whether N400 and P600 repetition effects are sensitive to further cognitive decline in PD. (JINS, 2017, 23, 78-89).

Semantic Feature Disturbance in Alzheimer Disease: Evidence from an Object Decision Task.

BACKGROUND AND OBJECTIVE: It is widely held that semantic disturbance in Alzheimer disease (AD) involves the loss of distinctive features but the relative sparing of nondistinctive features. Many previous studies of semantic feature disturbance have used cognitively challenging tasks with verbal stimuli that allow for potential cognitive confounds. Our objective was to use a task with lower memory demands to investigate distinctive feature disturbance in AD. METHODS: We used an object decision task to compare the processing of distinctive and nondistinctive semantic features in people with AD and age-matched controls. The task included six conditions based on the relationship between each prime and target object. We tested the processing of distinctive and nondistinctive features by selectively altering distinctive and nondistinctive semantic features between prime and target pairs. RESULTS: Performance accuracy was significantly lower for participants with AD than for age-matched controls when distinctive features were manipulated, but no difference was found when nondistinctive features were manipulated. CONCLUSIONS: Our results provide evidence of semantic content disturbance in AD in the context of a task with low cognitive demands.

Semantic Feature Training for the Treatment of Anomia in Alzheimer Disease: A Preliminary Investigation.

OBJECTIVE: This is a preliminary investigation into the effectiveness of semantic feature training for the treatment of anomia in Alzheimer disease (AD). BACKGROUND: Anomia is a common clinical characteristic of AD. It is widely held that anomia in AD is caused by the combination of cognitive deficits and progressive loss of semantic feature information. Therapy that aims to help participants relearn or retain semantic features should, therefore, help treat anomia in AD. METHODS: Two men with AD and one man with progressive nonfluent aphasia received 10 treatment sessions focused on relearning the names of 20 animals and 20 fruits. Within each category, half of the items were of high and half were of low typicality. We individualized treatment items to each participant, using items that each had not named correctly at baseline. Treatment sessions consisted of naming, category sorting, and semantic feature verification tasks. RESULTS: Both participants with AD showed post-treatment improvements in naming, and one maintained the treatment effects at 6-week follow-up. The semantic category of the treatment items influenced post-treatment outcomes, but typicality did not. In contrast to the participants with AD, the man with progressive nonfluent aphasia had no improvement in naming ability. CONCLUSIONS: Our results suggest the potential viability of semantic feature training to treat anomia in AD and, therefore, the need for further research.

To sleep or not to sleep? No effect of sleep on contextual word learning in younger adults.

This study investigated the effect of sleep on novel word learning through reading context. Seventy-four healthy young adults attended two testing sessions, with either overnight sleep (sleep group) or daytime wakefulness (wake group) occurring between the sessions. At the initial learning session, participants identified the hidden meanings of novel words embedded within sentence contexts and were subsequently tested on their recognition of the novel word meanings. A recognition test was also conducted at the delayed session. The analyses revealed comparable recognition of novel word meanings for the sleep and wake group at both the initial and the delayed session, indicating that there was no benefit of sleep compared with wakefulness for novel word learning through context. Overall, this study highlights the critical influence of encoding method on sleep-dependent learning, where not all forms of word learning appear to benefit from sleep for consolidation.

Putting "the broken bits together": A qualitative exploration of the impact of communication changes in dementia.

INTRODUCTION: Communication is an area of health and functioning that is profoundly affected by dementia. While it is known that people living with dementia and their care partners experience disruptions to daily activities and social engagement, detailed knowledge about the lived impact of dementia-related communication changes is lacking. This study sought an in-depth understanding of the lived experience of dementia-related communication changes and the associated impact, needs, and strategies. METHODS: As part of an overarching participatory design study, a qualitative (interpretive description) exploration was undertaken with people living with dementia and their care partners. Data from semi-structured interviews were analysed using thematic analysis. RESULTS: We interviewed 13 people living with dementia and 21 care partners and drew three themes and 10 subthemes from the interviews. The first theme illustrates how dementia changes communication which in turn changes life; the second captures the impact of changes on people living with dementia and care partners emotionally and in the context of relationships; and the third describes some positive and constructive ways of moving forward with dementia-related communication changes. CONCLUSIONS: Interventions to enhance function, participation, and wellbeing for people living with dementia and their care partners need to encompass support for communication changes. There is a need to ensure that people living with dementia feel dignified and respected during communication, and that care partners and inclusive communities are educated, trained, and supported to facilitate communication.

Modulations of right hemisphere connectivity in young children relates to the perception of spoken words.

The early school years shape a young brain's capability to comprehend and contextualize words within milliseconds of exposure. Parsing word sounds (phonological interpretation) and word recognition (enabling semantic interpretation) are integral to this process. Yet little is known about the causal mechanisms of cortical activity during these early developmental stages. In this study, we aimed to explore these causal mechanisms via dynamic causal modelling of event-related potentials (ERPs) acquired from 30 typically developing children (ages 6-8 years) as they completed a spoken word-picture matching task. Source reconstruction of high-density electroencephalography (128 channels) was used to ascertain differences in whole-brain cortical activity during semantically "congruent" and "incongruent" conditions. Source activations analyzed during the N400 ERP window identified significant regions-of-interest (pFWE<.05) localized primarily in the right hemisphere when contrasting congruent and incongruent word-picture stimuli. Dynamic causal models (DCMs) were tested on source activations in the fusiform gyrus (rFusi), inferior parietal lobule (rIPL), inferior temporal gyrus (rITG) and superior frontal gyrus (rSFG). DCM results indicated that a fully connected bidirectional model with self-(inhibiting) connections over rFusi, rIPL and rSFG provided the highest model evidence, based on exceedance probabilities derived from Bayesian statistical inferences. Connectivity parameters of rITG and rSFG regions from the winning DCM were negatively correlated with behavioural measures of receptive vocabulary and phonological memory (pFDR<.05), such that lower scores on these assessments corresponded with increased connectivity between temporal pole and anterior frontal regions. The findings suggest that children with lower language processing skills required increased recruitment of right hemisphere frontal/temporal areas during task performance.

A dual task priming investigation of right hemisphere inhibition for people with left hemisphere lesions.

BACKGROUND: During normal semantic processing, the left hemisphere (LH) is suggested to restrict right hemisphere (RH) performance via interhemispheric suppression. However, a lesion in the LH or the use of concurrent tasks to overload the LH's attentional resource balance has been reported to result in RH disinhibition with subsequent improvements in RH performance. The current study examines variations in RH semantic processing in the context of unilateral LH lesions and the manipulation of the interhemispheric processing resource balance, in order to explore the relevance of RH disinhibition to hemispheric contributions to semantic processing following a unilateral LH lesion. METHODS: RH disinhibition was examined for nine participants with a single LH lesion and 13 matched controls using the dual task paradigm. Hemispheric performance on a divided visual field lexical decision semantic priming task was compared over three verbal memory load conditions, of zero-, two- and six-words. Related stimuli consisted of categorically related, associatively related, and categorically and associatively related prime-target pairs. Response time and accuracy data were recorded and analyzed using linear mixed model analysis, and planned contrasts were performed to compare priming effects in both visual fields, for each of the memory load conditions. RESULTS: Control participants exhibited significant bilateral visual field priming for all related conditions (p < .05), and a LH advantage over all three memory load conditions. Participants with LH lesions exhibited an improvement in RH priming performance as memory load increased, with priming for the categorically related condition occurring only in the 2- and 6-word memory conditions. RH disinhibition was also reflected for the LH damage (LHD) group by the removal of the LH performance advantage following the introduction of the memory load conditions. CONCLUSIONS: The results from the control group are consistent with suggestions of an age related hemispheric asymmetry reduction and indicate that in healthy aging compensatory bilateral activation may reduce the impact of inhibition. In comparison, the results for the LHD group indicate that following a LH lesion RH semantic processing can be manipulated and enhanced by the introduction of a verbal memory task designed to engage LH resources and allow disinhibition of RH processing.

Memory and communication support strategies in dementia: effect of a training program for informal caregivers.

BACKGROUND: People with dementia have a range of needs that are met by informal caregivers. A DVD-based training program was developed using research-based strategies for memory and communication in dementia. The effectiveness of the training on the caregiver experience and the well-being of the person with dementia was evaluated. METHODS: A pre-test/post-test controlled trial was undertaken with caregiver-care-recipient dyads living in the community. Measures of the carers' knowledge of memory and communication strategies, burden, positive perceptions of caregiving, and perceptions of problem behaviors were taken pre- and three months post-intervention. The depression and well-being of the person with dementia were also evaluated. Satisfaction with the training and feedback were measured. RESULTS: Twenty-nine dyads (13 training group, 16 control group) participated. Bonferroni's correction was made to adjust for multiple comparisons, setting α at 0.00385. A significant improvement was found in caregivers' knowledge for the training group compared to the control group (p = 0.0011). The training group caregivers reported a reduction in the frequency of care recipient disruptive behaviors (p = 0.028) and increased perceptions of positive aspects of caregiving (p = 0.039), both at a level approaching significance. The training group care recipients had increased frequency of verbally communicated depressive behaviors at a level approaching significance (p = 0.0126). The frequency of observed depressive behaviors was not significantly different between groups. CONCLUSIONS: This approach to training for caregivers of people with dementia appears promising for its impact on knowledge and the caregiving experience. Further research could monitor the impact of the training on broader measures of depression and well-being, with a larger sample.

Dorsal and Ventral Cortical Connectivity Is Mediated by the Inferior Frontal Gyrus During Facilitated Naming of Pictures.

Background: It is well recognized that semantic processing and auditory repetition facilitate subsequent naming of pictures. However, the neurocognitive mechanisms that underpin these facilitation effects remain unclear. Materials and Methods: The current study utilized a dynamic causal modeling (DCM) approach to examine high-density electroencephalographic (128-channel EEG) recordings and investigate connectivity modulations during facilitated naming of pictures in 18 healthy older adults (mean age 61.50 years). Source reconstruction of event-related potentials was performed in two specific time windows, (1) 150-250 msec and (2) 300-500 msec, to establish the timescale of significant cortical activations present during participation of semantic and phonological tasks. Hypothesis-driven DCM of source-activated regions was tested to ascertain which model most likely explained the semantic and phonological conditions, respectively. Results: DCM results indicated that a common cortical network comprising dorsal and ventral cortical connections best explained EEG task data derived from repetition and semantic tasks. For repetition (phonological) tasks, this model featured long feedback, bidirectional connections from inferior frontal gyrus (IFG) to occipitotemporal areas. Semantic tasks were most plausibly explained by a model that featured a self-inhibiting connection over the IFG only. Conclusions: Findings from this study reveal that a common cortical model comprising pathways that include dorsal and ventral regions is appropriate for characterizing EEG naming facilitation data, and that distinct cortical connections explain differences between semantic and auditory repetition processes. These models could be repurposed for naming facilitation paradigms in patients with language difficulties to optimize prediction and responsiveness to such paradigms. Impact statement The combination of semantic (word-level) and phonological (sound-level) processing in the cortex facilitates one of the most robust responses-the naming of pictures. Here, dynamic causal modeling of high-density electroencephalography during facilitated naming tasks revealed a model consisting of common dorsal and ventral connections that best explained response to semantic and phonological stimuli. Within this cortical network, phonological facilitation involved a long-range connection from inferior frontal gyrus (IFG) to occipitotemporal regions, whereas semantic facilitation contributed to self-inhibition of the IFG. The IFG is therefore a key region mediating cortical activity when switching between phonological and semantic conditions.

Acquisition of novel word meaning via cross situational word learning: An event-related potential study.

Cross-situational statistical word learning (CSWL) refers to the process whereby participants learn new words by tracking ambiguous word-object co-occurrences across time. This study used event-related potentials to explore the acquisition of novel word meanings via CSWL in healthy adults. After learning to associate novel auditory words (e.g., 'ket') with familiar objects (e.g., sword), participants performed a semantic judgement task where the learned novel words were paired with a familiar word belonging to either the same (e.g., dagger) or a different (e.g., harp) semantic category. As a comparison, the task also included word pairs comprising two familiar words. The analyses revealed that the unrelated novel word pairs elicited a similar N400 to that of the unrelated familiar word pairs, but with a different hemispheric distribution (left hemisphere for novel words, right hemisphere for familiar words). These findings demonstrate rapid meaning acquisition via CSWL, which is reflected at a neurophysiological level.

Semantic fluency deficits and associated brain activity in Parkinson's disease with mild cognitive impairment.

People living with Parkinson's disease (PD) with poor verbal fluency have an increased risk of developing dementia. This study examines the neural mechanisms underpinning semantic fluency deficits in patients with PD with mild cognitive impairment (PD-MCI) compared to those without MCI (PD-NC) and control participants without PD (non-PD). Thirty-seven (37) participants with PD completed a cognitive assessment battery to identify MCI (13 PD-MCI). Twenty sex- and age-matched non-PD patients also participated. Participants were scanned (3T Siemens PRISMA) while performing semantic fluency, semantic switching, and automatic speech tasks. The number of responses and fMRI data for semantic generation and semantic switching were analyzed. Participants also completed a series of verbal fluency tests outside the scanner, including letter fluency. Participants with PD-MCI performed significantly worse than PD-NC and non-PD participants during semantic fluency and semantic switching tasks. PD-MCI patients showed greater activity in the right angular gyrus than PD-NC and non-PD patients during semantic switching. Increased right angular activity correlated with worse verbal fluency performance outside the scanner. Our study showed that the PD-MCI group performed worse on semantic fluency than either the PD-NC or non-PD groups. Increased right angular gyrus activity in participants with PD-MCI during semantic switching suggests early compensatory mechanisms, predicting the risk of future dementia in PD.

Memory and communication support in dementia: research-based strategies for caregivers.

BACKGROUND: Difficulties with memory and communication are prominent and distressing features of dementia which impact on the person with dementia and contribute to caregiver stress and burden. There is a need to provide caregivers with strategies to support and maximize memory and communication abilities in people with dementia. In this project, a team of clinicians, researchers and educators in neuropsychology, psychogeriatrics, nursing and speech pathology translated research-based knowledge from these fields into a program of practical strategies for everyday use by family and professional caregivers. METHODS: From the available research evidence, the project team identified compensatory or facilitative strategies to assist with common areas of difficulty, and structured these under the mnemonics RECAPS (for memory) and MESSAGE (for communication). This information was adapted for presentation in a DVD-based education program in accordance with known characteristics of effective caregiver education. RESULTS: The resultant DVD comprises (1) information on the nature and importance of memory and communication in everyday life; (2) explanations of common patterns of difficulty and preserved ability in memory and communication across the stages of dementia; (3) acted vignettes demonstrating the strategies, based on authentic samples of speech in dementia; and (4) scenarios to prompt the viewer to consider the benefits of using the strategies. CONCLUSION: Using a knowledge-translation framework, information and strategies can be provided to family and professional caregivers to help them optimize residual memory and communication in people with dementia. Future development of the materials, incorporating consumer feedback, will focus on methods for enabling wider dissemination.

The effect of sleep on novel word learning in healthy adults: A systematic review and meta-analysis.

There is increasing evidence to indicate that sleep plays a role in language acquisition and consolidation; however, there has been substantial variability in methodological approaches used to examine this phenomenon. This systematic review and meta-analysis aimed to investigate the effect of sleep on novel word learning in adults, and explore whether these effects differed by retrieval domain (i.e., recall, recognition, and tests of lexical integration). Twenty-five unique studies met the inclusion criteria for the review, and 42 separate outcome measures were synthesized in the meta-analysis (k = 29 separate between-group comparisons, n = 1,396 participants). The results from the omnibus meta-analysis indicated that sleep was beneficial for novel word learning compared with wakefulness (g = 0.50). Effect sizes differed across the separate domain-specific meta-analyses, with moderate effects for recall (g = 0.57) and recognition memory (g = 0.52), and a small effect for tasks which measured lexical integration (g = 0.39). Overall, the results of this meta-analysis indicate that sleep generally benefits novel word acquisition and consolidation compared with wakefulness across differing retrieval domains. This systematic review highlights the potential for sleep to be used to improve second-language learning in healthy adults, and overall provides further insight into methods to facilitate language development.

The influence of contextual constraint on verbal selection mechanisms and its neural correlates in Parkinson's disease.

A small number of studies have described verbal selection deficits in Parkinson's disease (PD) when selection must occur among competing alternatives. However, these studies have largely focused on single-word processing, or have utilised sentence stems that carry high contextual constraint, thus reducing selection demands. The present study aimed to determine the influence of variable contextual constraint on the selection of a verbal response in PD. This was achieved using an adaption of the Hayling Sentence Completion Task whereby PD participants and matched controls were required to provide a single word to complete a cloze probability sentence stem that carried a low, medium, or high degree of contextual constraint. Results revealed no main effect of group in terms of response time or accuracy, though a group-by-condition interaction in accuracy was noted. This was characterised by a significant difference in accuracy between low and medium levels of constraint for control participants, but no significant difference for the PD group. Functional MRI data revealed marked between-group differences in underlying neural activity. The control group showed increased recruitment of the dorsal striatum and the vlPFC under conditions that placed greater demands upon selection (i.e. low and medium constraint), and greater activity overall in the left dlPFC and right vlPFC. However, in the PD group, behavioural performance appeared to be maintained despite underlying decreases in frontostriatal activity, suggesting other compensatory mechanisms that may include changes in functional connectivity or an over-medication effect in frontal networks in response to loss of signalling in cortico-subcortical pathways.