The language network is not engaged in object categorization.

The relationship between language and thought is the subject of long-standing debate. One claim states that language facilitates categorization of objects based on a certain feature (e.g. color) through the use of category labels that reduce interference from other, irrelevant features. Therefore, language impairment is expected to affect categorization of items grouped by a single feature (low-dimensional categories, e.g. "Yellow Things") more than categorization of items that share many features (high-dimensional categories, e.g. "Animals"). To test this account, we conducted two behavioral studies with individuals with aphasia and an fMRI experiment with healthy adults. The aphasia studies showed that selective low-dimensional categorization impairment was present in some, but not all, individuals with severe anomia and was not characteristic of aphasia in general. fMRI results revealed little activity in language-responsive brain regions during both low- and high-dimensional categorization; instead, categorization recruited the domain-general multiple-demand network (involved in wide-ranging cognitive tasks). Combined, results demonstrate that the language system is not implicated in object categorization. Instead, selective low-dimensional categorization impairment might be caused by damage to brain regions responsible for cognitive control. Our work adds to the growing evidence of the dissociation between the language system and many cognitive tasks in adults.

The human language system, including its inferior frontal component in "Broca's area," does not support music perception.

Language and music are two human-unique capacities whose relationship remains debated. Some have argued for overlap in processing mechanisms, especially for structure processing. Such claims often concern the inferior frontal component of the language system located within "Broca's area." However, others have failed to find overlap. Using a robust individual-subject fMRI approach, we examined the responses of language brain regions to music stimuli, and probed the musical abilities of individuals with severe aphasia. Across 4 experiments, we obtained a clear answer: music perception does not engage the language system, and judgments about music structure are possible even in the presence of severe damage to the language network. In particular, the language regions' responses to music are generally low, often below the fixation baseline, and never exceed responses elicited by nonmusic auditory conditions, like animal sounds. Furthermore, the language regions are not sensitive to music structure: they show low responses to both intact and structure-scrambled music, and to melodies with vs. without structural violations. Finally, in line with past patient investigations, individuals with aphasia, who cannot judge sentence grammaticality, perform well on melody well-formedness judgments. Thus, the mechanisms that process structure in language do not appear to process music, including music syntax.

Stakeholder views on cognitive communication assessment and intervention for a person living independently in the community with severe traumatic brain injury.

BACKGROUND: Cognitive communication disorder (CCD) following traumatic brain injury (TBI) is well documented and these communication problems impede successful re-integration into community living. While there is growing evidence for intervention to both detect and treat the impact of these deficits across the rehabilitation continuum, there are barriers to accessing services. Cognitive communication impairments may be missed because the person can talk, and this may mask the subtle but debilitating impact of a CCD. Referral to a speech and language therapist (SLT) may be overlooked or not timely, which prevents the individual accessing evidence-based interventions. Inadequate treatment provision and an under- or overestimation of communication capability can potentially undermine the effectiveness of wider team assessment and intervention. AIMS: To report stakeholder views on specialist SLT input for CCD within a multidisciplinary team intervention for a community-dwelling individual with severe TBI. The investigation explored perspectives on understanding of CCD, on practice and on outcomes, in order to inform professional groups on perceived impacts of the evidence-to-practice gap. METHODS AND PROCEDURES: A semi-structured interview methodology was employed with 11 stakeholder participants involved in a single case. Data were evaluated using a thematic framework method. Themes were inductively derived from the stakeholder narratives. OUTCOMES: Stakeholders reported the following outcomes from specialist SLT input for CCD within a collaborative team approach: improved engagement with rehabilitation and support teams, improved health-related quality of life and well-being, and increased client participation in community activities of personal relevance. Stakeholders also reported inequities in wider service provision where limitations in professional understanding of CCD and knowledge of best practice recommendations preclude access to specialist SLT services. CONCLUSIONS: CCDs are under-recognised and this can have a devastating effect on people with CCD and on those around them. Stakeholder reports provide evidence for the effectiveness of SLT practice recommendations for the treatment of CCD following TBI. They also provide additional evidence of persisting barriers to accessing treatment. Future research to explore ways to close this evidence-to-practice gap is required. WHAT THIS PAPER ADDS: What is already known on this subject Cognitive communication difficulties are a well-documented consequence of TBI. There is evidence for the effectiveness of person-centred interventions for CCD across the recovery continuum. International evidence-based practice recommendations are in place for CCD assessment and management. Barriers to accessing SLT expertise for CCD have previously been reported. What this paper adds to existing knowledge This investigation explores the views of a diverse group of stakeholders involved in a single case of a community-dwelling individual with severe TBI. Stakeholders report positive real-world outcomes from SLT interventions for CCD within a coordinated multidisciplinary rehabilitation team. Stakeholder reports also indicate inequities in wider service provision and CCD knowledge gaps amongst professional groups providing rehabilitation services for people with TBI. What are the potential or actual clinical implications of this work? CCDs are under-recognised, with devastating effect for people with CCD and those around them. These findings underscore the importance of raising professional awareness of CCD and best practice recommendations, in order to improve access to SLT expertise for people with CCD following TBI.

Survey of tinnitus patients' acceptance of high-definition transcranial direct current stimulation as a management option.

OBJECTIVES: To investigate acceptance of high-definition transcranial direct current stimulation (HD-tDCS) as a management option for tinnitus. DESIGN: Participants completed an online version of the Tinnitus Functional Index (TFI), after which they recorded their satisfaction ratings with different hypothetical intervention outcomes on a 10-point rating scale using Opinio survey software. STUDY SAMPLE: Data from 272 tinnitus sufferers from English-speaking regions worldwide were collected, of which the majority had moderate to severe tinnitus as per TFI. RESULTS: The survey showed that HD-tDCS was considered an acceptable form of tinnitus management, and that the satisfaction rating depended significantly on a number of factors: (1) the strength of the tinnitus reduction following the intervention (p < 0.001); 2) the duration of the intervention (p < 0.001); and (3) the effects of the intervention on either tinnitus loudness or tinnitus-related distress (p < 0.001). Respondents rated their satisfaction with the intervention 10/10 only if it completely eliminated tinnitus loudness, although reductions of 50-80% were also rated highly acceptable. No association was found between tinnitus severity and acceptability ratings. CONCLUSIONS: These findings are important for future HD-tDCS trials for tinnitus, as they demonstrate the need to optimise stimulation protocols to increase effect sizes and decrease time spent on the treatment.

Training flexibility in fixed expressions in non-fluent aphasia: A case series report.

BACKGROUND: Many speakers with non-fluent aphasia (NFA) are able to produce some well-formed word combinations such as 'I like it' or 'I don't know', although they may not use variations such as 'He likes it' or 'I don't know that person'. This suggests that these utterances represent fixed forms. AIMS: This case series investigation explored the impact of a novel intervention aimed at enhancing the connected speech of individuals with NFA. The intervention, motivated by usage-based principles, involved filling open slots in semi-fixed sentence frames. METHODS & PROCEDURES: Five participants with NFA completed a 6-week intervention programme. The intervention trained participants to insert a range of different lexical items into the open slots of high-frequency phrases such as 'I like it' to enable more productive sentences (e.g., 'they like flowers'). The outcomes and acceptability were examined: The primary outcome measure focused on changes in connected narrative, and the availability of trained constructions (e.g., 'I like it') was explored through a story completion test. Two baseline measures of behaviour were taken prior to intervention, and outcomes assessed immediately after intervention and at a 6-week maintenance assessment. OUTCOME & RESULTS: A pre-/post-treatment comparison of connected speech measures showed evidence of enhanced connected speech for two of the five participants (P2 and P5). An analysis of story completion test scores revealed positive change for two participants (P1 and P2). Findings were mixed with regard to baseline stability of outcome measures and post-intervention stability of language changes. The intervention was acceptable to all participants. CONCLUSION & IMPLICATIONS: While this pilot study yielded promising findings with regard to the intervention's acceptability and increased connected speech for some participants, the findings were mixed across the sample of five participants. This research helps inform hypotheses and selection criteria for future studies. WHAT THIS PAPER ADDS: What is already known on the subject Despite difficulties producing grammatically correct sentences, many speakers with aphasia are able to produce well-formed utterances, often representing familiar expressions such as 'I don't know' and 'I like it'. In usage-based Construction Grammar (CxG) theories, familiar utterances are assumed to be processed as one unit and are therefore more resilient to brain damage. CxG assumes that residual utterances such as 'I like it' map onto more abstract sentence frames (e.g., '[REFERENT] like-TENSE [THING]'). What this paper adds to existing knowledge Sentence therapy, informed by CxG principles, is novel in aphasiology, and usage-based interventions need to be evaluated with regard to their impact on language processing at the connected speech level. This case series report explores the acceptability and outcomes of a usage-based sentence therapy. We also introduce and explore the value of an automated, frequency-based analysis tool for evaluating connected speech outcomes in aphasia therapy. What are the potential or actual clinical implications of this work? The findings inform further development of usage-based aphasia interventions targeting word combinations.

Assessing emergence from a prolonged disorder of consciousness: Current opinion and practice in the UK.

BACKGROUND: A patient in PDOC must demonstrate functional object use or functional communication to confirm they have emerged from this state. A range of tasks and stimuli are used and patients must achieve 100% accuracy. As consciousness occurs along a continuum, determining emergence is not straightforward. OBJECTIVE: To establish the opinions of expert clinicians on how emergence is determined in practice. METHODS: An online survey was completed by clinicians working in specialist rehabilitation settings across the UK. Questions were asked about diagnosis and confidence, informal assessment, formal assessment, and family involvement. Descriptive statistics were used to analyse responses to closed questions. Responses to open questions were analysed using thematic analysis. RESULTS: Seventy-five surveys were analysed. Approximately a third (30.4 %) used tasks other than those recommended to determine emergence. A lack of confidence in tasks to detect the return of functional communication was reported by 46.4%. The majority (78.6%) reported they worked with patients who they felt had emerged, but could not demonstrate it based on the current criteria. A range of stimuli were employed, but 30.6% of respondents were not confident they could choose stimuli appropriately. Respondents reported a range of benefits and challenges when involving family in assessment.

Measuring outcomes of a peer-led social communication skills intervention for adults with acquired brain injury: A pilot investigation.

Reduced social competence following severe acquired brain injury (ABI) is well-documented. This pilot study investigated a peer-led group intervention based on the claim that peer models may be a more effective mechanism for behaviour change than clinician-led approaches. Twelve participants with severe ABI were recruited from a post-acute neurorehabilitation setting and randomly assigned to either a peer-led intervention or a staff-led activity group (usual care) (Clinicaltrials.gov: NCT02211339). The groups met twice a week for 8 weeks. A peer was trained separately to facilitate interaction in the intervention group. Training comprised 16 individual sessions over 4 weeks. Group behaviour was measured twice at baseline, after intervention and at maintenance (4 weeks), using the Adapted Measure of Participation in Conversation (MPC) and the Interactional Network Tool (INT), a newly devised measure of group conversational interaction. Outcome measures showed differential sensitivity. The groups did not differ in baseline behaviour. Findings showed a significant improvement in the treated group on the MPC transaction scale post-intervention (p = .02). The intervention group showed more balanced interaction post-intervention on the INT and at follow-up. Findings show preliminary evidence of the advantage for peer-led groups. The INT shows promise as a method to detect a change in group communication behaviour.Trial registration: ClinicalTrials.gov identifier: NCT02211339.

Comprehension of Embedded Clauses in Schizophrenia With and Without Formal Thought Disorder.

Formal thought disorder (FTD) in schizophrenia (SZ) is clinically manifested primarily through language production, where linguistic studies have reported numerous anomalies including lesser use of embedded clauses. Here, we explored whether problems of language may extend to comprehension and clause embedding in particular. A sentence-picture matching task was designed with two conditions in which embedded clauses were presupposed as either true (factive) or not. Performance across these two conditions was compared in people with SZ and moderate-to-severe FTD (SZ + FTD), SZ with minimal FTD (SZ-FTD), first-degree relatives of people with SZ, and neurotypical controls. The SZ + FTD group performed significantly worse than all others in both conditions, and worse in the nonfactive than in the factive one. These results demonstrate language dysfunction in comprehension specific to FTD is a critical aspect of grammatical complexity and its associated meaning, which has been independently known to be cognitively significant as well.

Language in schizophrenia and aphasia: the relationship with non-verbal cognition and thought disorder.

Objective: To determine the relationship between language abnormalities and broader cognitive impairment and thought disorder by examining language and cognition in schizophrenia and aphasia (a primary language disorder).Methods: Cognitive and linguistic profiles were measured with a battery of standardised tests, and compared in a clinical population of n = 50 (n = 30 with schizophrenia and n = 20 with aphasia) and n = 61 non-clinical comparisons (n = 45 healthy controls and n = 16 non-affected first-degree relatives of patients with schizophrenia).Results: Both clinical groups showed linguistic deficits. Verbal impairment was more severe in participants with aphasia, whereas non-verbal performance was more affected in participants with schizophrenia. In schizophrenia, but not in aphasia, verbal and non-verbal performance were associated. Formal thought disorder was associated with impairment in executive function and in grammatical, but not naming, tasks.Conclusion: While patients with schizophrenia and aphasia showed language impairments, the nature and cognitive basis of these impairments may be different; language performance disassociates from broader cognitive functioning in aphasia but may be an intrinsic expression of a broader cognitive impairment in schizophrenia. Thought disorder may represent a core malfunction of grammatical processing. Results suggests that communicative ability may be a valid target in cognitive remediation strategies in schizophrenia.

Self-Administered Computer Therapy for Apraxia of Speech: Two-Period Randomized Control Trial With Crossover.

BACKGROUND AND PURPOSE: There is currently little evidence on effective interventions for poststroke apraxia of speech. We report outcomes of a trial of self-administered computer therapy for apraxia of speech. METHODS: Effects of speech intervention on naming and repetition of treated and untreated words were compared with those of a visuospatial sham program. The study used a parallel-group, 2-period, crossover design, with participants receiving 2 interventions. Fifty participants with chronic and stable apraxia of speech were randomly allocated to 1 of 2 order conditions: speech-first condition versus sham-first condition. Period 1 design was equivalent to a randomized controlled trial. We report results for this period and profile the effect of the period 2 crossover. RESULTS: Period 1 results revealed significant improvement in naming and repetition only in the speech-first group. The sham-first group displayed improvement in speech production after speech intervention in period 2. Significant improvement of treated words was found in both naming and repetition, with little generalization to structurally similar and dissimilar untreated words. Speech gains were largely maintained after withdrawal of intervention. There was a significant relationship between treatment dose and response. However, average self-administered dose was modest for both groups. Future software design would benefit from incorporation of social and gaming components to boost motivation. CONCLUSIONS: Single-word production can be improved in chronic apraxia of speech with behavioral intervention. Self-administered computerized therapy is a promising method for delivering high-intensity speech/language rehabilitation. CLINICAL TRIAL REGISTRATION: URL: http://orcid.org/0000-0002-1278-0601. Unique identifier: ISRCTN88245643.

The impact of ageing on the health and wellbeing of people with thalidomide embryopathy: a comparison of the health impact with the general population.

PURPOSE: As people living with thalidomide embryopathy (TE) are now entering their seventh decade, we examine the impact of ageing and the prevalence of comorbid health conditions reported in holistic needs assessments (HNAs) by individuals with TE, compare it with an age-matched sample of the general population, and explore the relationship between comorbidities and TE pattern of impairment. MATERIALS AND METHODS: The HNA categories were mapped and compared to those of the Health Survey for England (HSE) and analysed across four impairment groups (A-D). RESULTS: 94% (392/415) of individuals with TE residing in the UK participated in the HNA and consented to a secondary analysis of the data. Less than 2% (5/392) reported no comorbidities; 94% reported nervous system problems; including pain, pins and needles and numbness. Individuals with TE reported a significantly greater number of health comorbidities, including musculoskeletal problems, than the age-matched HSE population. CONCLUSIONS: Individuals with TE report significantly more health and well-being concerns than the general population of a similar age. Long-term monitoring is needed to ensure that support and rehabilitation services can meet their evolving needs.

People living with thalidomide's teratogenic effects are now entering their seventh decade.As they age, these individuals experience the long-term consequences linked to over-use of certain joints, including musculoskeletal and neuropathic pain.An understanding of the lived experience of TE with increasing age has the potential to inform the planning and provision of adequate and appropriate rehabilitation services moving forward.Adoption of a holistic approach to rehabilitation could help people living with TE to maintain functional independence as they enter their seventh decade.

COS-PPA: protocol to develop a core outcome set for primary progressive aphasia.

INTRODUCTION: The term primary progressive aphasia (PPA) describes a group of language-led dementias. Disease-modifying treatments that delay, slow or reverse progression of PPA are currently lacking, though a number of interventions to manage the symptoms of PPA have been developed in recent years. Unfortunately, studies exploring the effectiveness of these interventions have used a variety of different outcome measures, limiting comparability. There are more constructs, apart from word retrieval, that are important for people with PPA that have not received much attention in the research literature. Existing core outcome sets (COS) for dementia and non-progressive aphasia do not meet the needs of people with PPA, highlighting a need to develop a specific COS for PPA. METHODS AND ANALYSIS: This protocol describes a three-stage study to identify a COS for PPA interventions in research and clinical practice. The stage 1 systematic review will identify existing speech, language and communication measures used to examine the effectiveness of interventions for PPA in the research literature. Employing a nominal group technique, stage 2 will identify the most important outcomes for people with PPA and their families. The data collected in stages 1 and 2 will be jointly analysed with the project PPI group and will inform the stage 2 modified Delphi consensus study to identify a core outcome measurement set for PPA among a range of research disciplines undertaking intervention studies for people with PPA. ETHICS AND DISSEMINATION: Ethical approval for stage 2 of the study has been sought individually in each country at collaborating institutions and is stated in detail in the manuscript. Stage 3 has been granted ethical approval by the Chairs of UCL Language and Cognition Department Ethics, Project ID LCD-2023-06. Work undertaken at stages 1, 2 and 3 will be published in open-access peer-reviewed journal articles and presented at international scientific conferences. PROSPERO REGISTRATION NUMBER: CRD42022367565.

Differentiating core and co-opted mechanisms in calculation: the neuroimaging of calculation in aphasia.

The role of language in exact calculation is the subject of debate. Some behavioral and functional neuroimaging investigations of healthy participants suggest that calculation requires language resources. However, there are also reports of individuals with severe aphasic language impairment who retain calculation ability. One possibility in resolving these discordant findings is that the neural basis of calculation has undergone significant reorganization in aphasic calculators. Using fMRI, we examined brain activations associated with exact addition and subtraction in two patients with severe agrammatic aphasia and retained calculation ability. Behavior and brain activations during two-digit addition and subtraction were compared to those of a group of 11 healthy, age-matched controls. Behavioral results confirmed that both patients retained calculation ability. Imaging findings revealed individual differences in processing, but also a similar activation pattern across patients and controls in bilateral parietal cortices. Patients differed from controls in small areas of increased activation in peri-lesional regions, a shift from left fronto-temporal activation to the contralateral region, and increased activations in bilateral superior parietal regions. Our results suggest that bilateral parietal cortex represents the core of the calculation network and, while healthy controls may recruit language resources to support calculation, these mechanisms are not mandatory in adult cognition.

Verbal ability in postmenopausal women in relation to age, cognitive and reproductive factors.

Word-finding difficulties have been associated with age and, in women, lowered sex hormone levels following menopause. However, there is limited understanding of the ways that specific aspects of word-finding are shaped by women's age, reproductive histories, and background factors such as education. The current study investigated the effects of age, cognitive and reproductive factors on word-finding abilities in 53 healthy postmenopausal women aged 48-79. A questionnaire was used to gather demographic information and reproductive history. A battery of verbal fluency, continuous series, and naming tasks was designed to assess word-finding across different sensory modalities and cognitive demands. Category and letter fluency were quantified as total number of correct words produced on each task. For continuous series, switch rates and switch costs were computed. For the naming tasks, accuracy and latency measures were used. There were three key findings. Firstly, there was a consistent positive association between education and all word-finding measures, i.e., verbal fluency, continuous series, and naming. Secondly, age-related declines were seen on tasks heavily dependent on working memory such as the continuous series task. Thirdly, reproductive factors across the lifespan such as age at menarche and reproductive years showed subtle effects on naming abilities, but not on verbal fluency or continuous series. The results highlight that word-finding abilities in healthy postmenopausal women are shaped by factors associated with their early years (education, age at menarche) and later adult life (age, reproductive years). The study also distinguished between the more global effects of education, and the more task-specific associations with age and reproductive variables, on verbal task performance after menopause.

Benefit of visual speech information for word comprehension in post-stroke aphasia.

Aphasia is a language disorder that often involves speech comprehension impairments affecting communication. In face-to-face settings, speech is accompanied by mouth and facial movements, but little is known about the extent to which they benefit aphasic comprehension. This study investigated the benefit of visual information accompanying speech for word comprehension in people with aphasia (PWA) and the neuroanatomic substrates of any benefit. Thirty-six PWA and 13 neurotypical matched control participants performed a picture-word verification task in which they indicated whether a picture of an animate/inanimate object matched a subsequent word produced by an actress in a video. Stimuli were either audiovisual (with visible mouth and facial movements) or auditory-only (still picture of a silhouette) with audio being clear (unedited) or degraded (6-band noise-vocoding). We found that visual speech information was more beneficial for neurotypical participants than PWA, and more beneficial for both groups when speech was degraded. A multivariate lesion-symptom mapping analysis for the degraded speech condition showed that lesions to superior temporal gyrus, underlying insula, primary and secondary somatosensory cortices, and inferior frontal gyrus were associated with reduced benefit of audiovisual compared to auditory-only speech, suggesting that the integrity of these fronto-temporo-parietal regions may facilitate cross-modal mapping. These findings provide initial insights into our understanding of the impact of audiovisual information on comprehension in aphasia and the brain regions mediating any benefit.

The role of number words: the phonological length effect in multidigit addition.

We explored the role of phonological representations of number words in exact calculation. The reaction times and accuracy of responses in multidigit addition problems were compared across three groups of participants (young healthy, older healthy, and 3 patients with severe aphasia) and two types of addition problems: phonologically long in English (containing the bisyllabic number word "seven") and short in English (monosyllabic number words-e.g., "six"). Older healthy participants were significantly faster and more accurate in calculation than younger healthy participants. The older participants showed no evidence of a phonological length effect. However this effect was apparent in the younger adults, with longer reaction times on phonologically long problems. Furthermore, there was an association between the presence of a phonological length effect and the overall speed of response, suggesting that less proficient calculators were more reliant on phonological mediation of performance. The aphasic participants retained the ability to complete multidigit additions and were as accurate as the younger healthy group, although the response times of two of the 3 patients were slow. The aphasic participants varied with regard to the presence of a phonological length effect. Two participants showed no evidence of phonological mediation, while 1 displayed a phonological length effect. The results suggest that language resources are not mandatory for exact addition, although they may be used to scaffold math performance in less competent calculators. Evidence of phonological mediation of performance in aphasic participants may provide insight into the integrity or otherwise of inner speech in severe aphasia.

Error reduction therapy in reducing struggle and grope behaviours in apraxia of speech.

We report an intervention study focused on the speech production difficulties present in acquired apraxia of speech (AOS). The intervention was a self-administered computer therapy that targeted whole word production and incorporated error reduction strategies. The effectiveness of the therapy was contrasted to that of a visuospatial sham computer program, and performance across treated words, and two sets of matched words, was assessed. Two groups of participants completed the study which employed a two-phase cross-over treatment design. Participants were randomly assigned to a speech first or sham first condition. Treatments were administered for six weeks, with a four week rest between interventions. Participants were assessed five times in total; twice at baseline, once following each of the intervention phases, and once following a lapse of eight weeks after the end of the second phase of intervention. The occurrence of accurate word production and speech characterised by struggle and groping behaviours was recorded on a repetition task. Participants showed significant gains in speech accuracy and fluency, and reductions in articulatory groping and struggle behaviours following the use of the speech program. These gains were largely maintained once the therapy was withdrawn.

Determiner primes as facilitators of lexical retrieval in English.

Gender priming studies have demonstrated facilitation of noun production following pre-activation of a target noun's grammatical gender. Findings provide support for models in which syntactic information relating to words is stored within the lexicon and activated during lexical retrieval. Priming effects are observed in the context of determiner plus noun phrase production. Few studies demonstrate gender priming effects in bare noun production (i.e., nouns in isolation). We investigated the effects of English determiner primes on bare mass and count noun production. In two experiments, participants named pictures after exposure to primes involving congruent, incongruent and neutral determiners. Facilitation of noun production by congruent and neutral determiner primes was found in both experiments. The results suggest that noun phrase syntax is activated in lexical retrieval, even when not explicitly required for production. Post hoc analysis of the relative frequency of congruent and incongruent prime-target pairs provides support for a frequency-based interpretation of the data.

The role of iconic gestures and mouth movements in face-to-face communication.

Human face-to-face communication is multimodal: it comprises speech as well as visual cues, such as articulatory and limb gestures. In the current study, we assess how iconic gestures and mouth movements influence audiovisual word recognition. We presented video clips of an actress uttering single words accompanied, or not, by more or less informative iconic gestures. For each word we also measured the informativeness of the mouth movements from a separate lipreading task. We manipulated whether gestures were congruent or incongruent with the speech, and whether the words were audible or noise vocoded. The task was to decide whether the speech from the video matched a previously seen picture. We found that congruent iconic gestures aided word recognition, especially in the noise-vocoded condition, and the effect was larger (in terms of reaction times) for more informative gestures. Moreover, more informative mouth movements facilitated performance in challenging listening conditions when the speech was accompanied by gestures (either congruent or incongruent) suggesting an enhancement when both cues are present relative to just one. We also observed (a trend) that more informative mouth movements speeded up word recognition across clarity conditions, but only when the gestures were absent. We conclude that listeners use and dynamically weight the informativeness of gestures and mouth movements available during face-to-face communication.

Individual behavior in learning of an artificial grammar.

Artificial grammar learning (AGL) is a widely used experimental paradigm that investigates how syntactic structures are processed. After a familiarization phase, participants have to distinguish strings consistent with a set of grammatical rules from strings that violate these rules. Many experiments report performance solely at a group level and as the total number of correct judgments. This report describes a systematic approach for investigating individual performance and a range of different behaviors. Participants were exposed to strings of the nonfinite grammar A( n )B( n ). To distinguish grammatical from ungrammatical strings, participants had to pay attention to local dependencies while comparing the number of stimuli from each class. Individual participants showed substantially different behavioral patterns despite exposure to the same stimuli. The results were replicated across auditory and visual sensory modalities. It is suggested that an analysis that looks at individual differences grants new insights into the processes involved in AGL. It also provides a solid basis from which to investigate sequence-processing abilities in special populations, such as patients with neurological lesions.