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1.
PLoS One ; 16(3): e0242754, 2021.
Article in English | MEDLINE | ID: mdl-33661954

ABSTRACT

In language, stored semantic representations of lexical items combine into an infinitude of complex expressions. While the neuroscience of composition has begun to mature, we do not yet understand how the stored representations evolve and morph during composition. New decoding techniques allow us to crack open this very hard question: we can train a model to recognize a representation in one context or time-point and assess its accuracy in another. We combined the decoding approach with magnetoencephalography recorded during a picture naming task to investigate the temporal evolution of noun and adjective representations during speech planning. We tracked semantic representations as they combined into simple two-word phrases, using single words and two-word lists as non-combinatory controls. We found that nouns were generally more decodable than adjectives, suggesting that noun representations were stronger and/or more consistent across trials than those of adjectives. When training and testing across contexts and times, the representations of isolated nouns were recoverable when those nouns were embedded in phrases, but not so if they were embedded in lists. Adjective representations did not show a similar consistency across isolated and phrasal contexts. Noun representations in phrases also sustained over time in a way that was not observed for any other pairing of word class and context. These findings offer a new window into the temporal evolution and context sensitivity of word representations during composition, revealing a clear asymmetry between adjectives and nouns. The impact of phrasal contexts on the decodability of nouns may be due to the nouns' status as head of phrase-an intriguing hypothesis for future research.


Subject(s)
Brain/physiology , Semantics , Adult , Female , Humans , Magnetoencephalography , Male , Psycholinguistics
2.
Autism ; 23(7): 1793-1804, 2019 10.
Article in English | MEDLINE | ID: mdl-30823851

ABSTRACT

Autism spectrum disorder is characterized by difficulties with social communication, with a preponderance in males. Evidence supports a relationship between metacognitive executive functions (e.g. planning, working memory) and social communication in autism spectrum disorder, yet relationships with specific metacognitive executive functions and how gender alters the expression of these relationships require further study. We used multiple regression to examine relationships between informant-based measures of metacognitive executive function and social communication in intellectually able (IQ ⩾ 85) female (n = 111; mean age = 10.2 ± 2.8; 31 autism spectrum disorder) and male youth (n = 310; mean age = 10.5 ± 1.9; 146 autism spectrum disorder) with and without autism spectrum disorder from the Autism Brain Imaging Data Exchange-II database. Executive function-social communication relationships were different in females and males with autism spectrum disorder. Relationships between the entire metacognitive index and social communication were stronger in males with autism spectrum disorder than without; this pattern was also observed for metacognitive sub-indices 'monitor' and 'working memory'. These patterns were not observed in females. Relationships between executive function and social communication appear different for female and male youth with an autism spectrum disorder diagnosis. To better understand the nature of metacognitive contributions to social communication in autism spectrum disorder, future work should investigate the co-development of monitoring, working memory and social communication, while taking gender into account.


Subject(s)
Autism Spectrum Disorder/psychology , Communication , Executive Function , Interpersonal Relations , Social Behavior , Case-Control Studies , Child , Child Behavior/psychology , Female , Humans , Male , Metacognition , Psychological Tests , Sex Factors
3.
Infant Behav Dev ; 54: 1-12, 2019 02.
Article in English | MEDLINE | ID: mdl-30508782

ABSTRACT

Online testing of infants by recording video with a webcam has the potential to improve the replicability of developmental studies by facilitating larger sample sizes and by allowing methods (including recruitment) to be specified in code. However, the recorded video still needs to be manually scored. This labour-intensive process puts downward pressure on sample sizes and requires subjective judgements that may not be reproducible in a different laboratory. Here we present the first fully automatic pipeline, using a face analysis software-as-a-service and a discriminant-analysis classifier to score infant videos acquired online. We compare human and machine performance for looking time and preferential looking paradigms; machine performance demonstrates a promising proof of principle for looking time and is above chance in classifying preferential looking. Additionally, we studied the characteristics of the video and the child that influenced automated scoring, so that future studies can acquire data that maximises the performance of automatic gaze coding and/or focus on improving automatic coding for particularly challenging data. We believe this technology has great promise for developmental science.


Subject(s)
Biometric Identification/methods , Facial Recognition/physiology , Infant Behavior/physiology , Video Recording/methods , Discriminant Analysis , Female , Humans , Infant , Infant Behavior/psychology , Intention , Male , Software
4.
Neuroscience ; 361: 19-33, 2017 Oct 11.
Article in English | MEDLINE | ID: mdl-28802915

ABSTRACT

Because of their difficulties with figurative language in conversation, it is commonly thought that individuals with autism spectrum disorder (ASD) do not understand figurative meaning. However, recent research indicates that individuals with and without ASD are similar in the first two stages of metaphor comprehension, up to and including successful generation of the figurative meaning. In the current study, we used a sentence decision task to evaluate the subsequent stage of metaphor comprehension, the selection stage, which requires suppression/inhibition of the unintended meaning as part of selecting the intended meaning. fMRI activation and functional connectivity were used to compare the selection stage of metaphor comprehension between high-functioning individuals with ASD and carefully matched controls. Cortical and subcortical regions of interest were selected based on the basal-ganglia model of cognitive control. Compared to controls, individuals with ASD recruited greater activation in regions related to verbal memory (thalamus), semantic associations (medial temporal gyrus), and basic visual processing (middle occipital gyrus). Functional connectivity analysis revealed fewer overall connections and cortical-subcortical connections in the ASD group compared to controls. There was a novel finding of maintenance of subcortical-subcortical connectivity in the ASD group, specific to the selection condition, despite differences in cortically involved connections. Reduced cortical-subcortical connectivity in the ASD group compared to controls may reflect a more global impairment in cognitive control pathways, while consistent subcortical-subcortical connectivity may reflect systemic inflexibility or preserved subcortical function and dissociation between subcortical and cortical systems. Further investigation is required.


Subject(s)
Autism Spectrum Disorder/physiopathology , Comprehension/physiology , Language , Metaphor , Adolescent , Adult , Brain Mapping , Female , Humans , Language Tests , Male , Middle Aged , Neurologic Examination/methods , Reaction Time/physiology , Young Adult
5.
Hum Brain Mapp ; 38(9): 4413-4429, 2017 09.
Article in English | MEDLINE | ID: mdl-28580693

ABSTRACT

Eight children (3 females; 8-16 years) with motor speech disorders secondary to cerebral palsy underwent 4 weeks of an intensive neuroplasticity-principled voice treatment protocol, LSVT LOUD® , followed by a structured 12-week maintenance program. Children were asked to overtly produce phonation (ah) at conversational loudness, cued-phonation at perceived twice-conversational loudness, a series of single words, and a prosodic imitation task while being scanned using fMRI, immediately pre- and post-treatment and 12 weeks following a maintenance program. Eight age- and sex-matched controls were scanned at each of the same three time points. Based on the speech and language literature, 16 bilateral regions of interest were selected a priori to detect potential neural changes following treatment. Reduced neural activity in the motor areas (decreased motor system effort) before and immediately after treatment, and increased activity in the anterior cingulate gyrus after treatment (increased contribution of decision making processes) were observed in the group with cerebral palsy compared to the control group. Using graphical models, post-treatment changes in connectivity were observed between the left supramarginal gyrus and the right supramarginal gyrus and the left precentral gyrus for the children with cerebral palsy, suggesting LSVT LOUD enhanced contributions of the feedback system in the speech production network instead of high reliance on feedforward control system and the somatosensory target map for regulating vocal effort. Network pruning indicates greater processing efficiency and the recruitment of the auditory and somatosensory feedback control systems following intensive treatment. Hum Brain Mapp 38:4413-4429, 2017. © 2017 Wiley Periodicals, Inc.


Subject(s)
Brain/physiopathology , Cerebral Palsy/physiopathology , Cerebral Palsy/rehabilitation , Voice Training , Adolescent , Analysis of Variance , Brain/diagnostic imaging , Cerebral Palsy/diagnostic imaging , Child , Female , Humans , Magnetic Resonance Imaging , Male , Neuronal Plasticity/physiology , Phonation , Treatment Outcome , Voice
6.
Healthc Q ; 19(4): 74-80, 2017.
Article in English | MEDLINE | ID: mdl-28130956

ABSTRACT

Children with autism spectrum disorder often develop persistent challenging behaviours. A previous study in this journal (Reynolds et al. 2011) reported effective implementation of strategies immediately following involvement in a comprehensive positive behaviour support workshop for parents/school personnel. The current study assessed long-term efficacy more than six months after workshop completion. Parent and school behaviour scores suggested maintained improvement in child behaviour. Parent responses to a verbal questionnaire revealed important perceptions of what made workshop participation beneficial. This study provides evidence for long-term benefits from this innovative approach for caregivers working with children with challenging behaviours.


Subject(s)
Autism Spectrum Disorder/psychology , Education/methods , Parents/education , Alberta , Child , Humans , Longitudinal Studies , Schools , Surveys and Questionnaires
7.
Am J Speech Lang Pathol ; 25(3): 269-89, 2016 08 01.
Article in English | MEDLINE | ID: mdl-27537490

ABSTRACT

PURPOSE: Magnetic resonance imaging (MRI), an influential experimental approach, provides valuable information about clinical disorders that can be used to select and/or refine speech and language interventions. Functional MRI (fMRI) in particular is becoming a widespread methodological tool for investigating speech and language. However, because MRI is relatively new and complex, potential consumers need to be able to critically assess the methods used in order to appraise results and conclusions. The authors offer a tutorial that (a) relays foundational knowledge related to the collection and analysis of MRI data in general and fMRI data specifically and (b) presents strategies for evaluating studies that utilize fMRI methods. METHOD: This tutorial outlines methodological considerations that should be addressed by fMRI researchers and noted by consumers of the research, including clinicians and behavioral researchers who work with neurogenic communication disorders. RESULTS: Readers will be able to evaluate a neuroimaging publication and identify the methodological strengths and weaknesses that potentially influence the integrity of reported findings and interpretations. CONCLUSION: This tutorial provides information and strategies that can be used to critically evaluate studies that collect, analyze, and interpret fMRI data. The tutorial concludes with a summary checklist to guide critical appraisal.


Subject(s)
Magnetic Resonance Imaging , Speech Disorders/diagnostic imaging , Humans , Language , Neuroimaging , Research , Speech
8.
Behav Brain Res ; 275: 157-65, 2014 Dec 15.
Article in English | MEDLINE | ID: mdl-25172183

ABSTRACT

Although rapid automatized naming (RAN) of letters, digits, and objects are popular tasks and have been used interchangeably to predict academic performance, it remains unknown if they tap into the same neural regions. Thus, the purpose of this study was to examine the neural overlap across different RAN tasks. Fifteen university students were assessed on RAN digits, letters, and objects using functional magnetic resonance imaging (fMRI). Results showed a common neural pattern that included regions related to motor planning (e.g., cerebellum), semantic access (middle temporal gyrus), articulation (supplementary motor association, motor/pre-motor, anterior cingulate cortex), and grapheme-phoneme mapping (ventral supramarginal gyrus). However, RAN digits and letters showed many unique regions of activation over and above RAN objects particularly in semantic and articulatory regions, including precuneus, bilateral supramarginal gyrus, nucleus accumbens and thalamus. The only region unique to RAN objects included bilateral fusiform, a region commonly implicated in object processing. Overall, our results provide the first neural evidence for a stronger relationship between RAN letters and digits than when either task is compared to RAN objects.


Subject(s)
Automatism , Brain/physiology , Neuropsychological Tests , Pattern Recognition, Visual/physiology , Reading , Adolescent , Adult , Brain/blood supply , Brain Mapping , Female , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male , Mathematics , Numerical Analysis, Computer-Assisted , Oxygen/blood , Statistics, Nonparametric , Young Adult
9.
Brain Lang ; 125(2): 203-14, 2013 May.
Article in English | MEDLINE | ID: mdl-22632813

ABSTRACT

Neurobiology of reading research has yet to explore whether reliance on the ventral-lexical stream during word reading can be enhanced by the instructed reading strategy, or whether it is impervious to such strategies. We examined Instructions: name all vs. name words (based on spelling), Word Type: regular words vs. exception words, and Word Frequency (WF) in print (log10 HAL WF) in an experiment while measuring fMRI BOLD and overt naming reaction time (RT) simultaneously. Instructions to name words increased overall reliance on the ventral-lexical stream, as measured by visible BOLD activation and the WF effect on RT, with regular words showing the greatest effects as a function of this reading strategy. Furthermore, the pattern of joint effects of these variables on RT supports the notion of cascaded, not parallel, processing. These results can be accommodated by dual-stream cascaded models of reading, and present a challenge to single-mechanism parallel processing models.


Subject(s)
Reaction Time/physiology , Reading , Verbal Behavior/physiology , Adult , Female , Humans , Magnetic Resonance Imaging , Male , Neuroimaging/methods , Semantics , Young Adult
10.
Brain Topogr ; 25(3): 293-307, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22124535

ABSTRACT

The aim of this study is to evaluate the data from a participant in a reading study who had a diagnosis of Meares-Irlen syndrome/visual stress (MISViS). MISViS is characterised by visual distortions and somatic issues, which are remediated using coloured filters. The authors present a case study providing descriptive neurobiological comparisons of MISViS versus a control group. The study involved eleven English language speakers who participated in behavioural and neuroimaging versions of a language experiment with varied proportions of regular and exception words. Behavioural measures included accuracy and response times. Neuroimaging was conducted using a 1.5T Siemens Sonata MRI. The MISViS participant's data were removed from the overall experiment and analysed as a case study. Impulse response functions (IRFs) and percentage of active voxels were extracted from four regions of interest: BAs 17, 18, 19, and the postcentral gyrus (PG) and two control regions (BA6 and left BA45). The results indicated that significant differences existed between the control group and the MISViS participant for IRF intensity in two regions (BA6 and PG) and percentage of active voxels in four regions (BA17, BA19, PG, and BA6). No significant differences occurred in left BA45 for either variable of interest. No significant differences were found for behavioural measures. In conclusion, our findings offer one of the first neurobiological descriptions of differences in IRF intensity and percentage of active voxels in visual and somatosensory cortex during a language experiment for a participant with MISViS in the absence of migraine compared to controls.


Subject(s)
Brain/physiopathology , Perceptual Disorders/physiopathology , Vision Disorders/physiopathology , Visual Perception , Adult , Brain Mapping , Case-Control Studies , Female , Functional Neuroimaging , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Perceptual Distortion , Reaction Time , Reading , Syndrome
11.
J Psycholinguist Res ; 40(5-6): 367-78, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21928093

ABSTRACT

The Frequency (high vs. low) × Regularity (regular vs. exception) interaction found on naming response times is often taken as evidence for parallel processing of sub-lexical and lexical systems. Using a Go/No-go naming task, we investigated the effect of nonword versus pseudohomophone foils on sub-lexical processing and the subsequent Frequency × Regularity interaction. We ran two experiments: (1) a Go/No-go naming task with nonword foils (e.g., bint) and (2) a Go/No-go naming task with pseudohomophone foils (e.g., pynt). Experiment 1 replicated the Frequency × Regularity interaction on naming response times supporting the notion of parallel sub-lexical and lexical processing. Experiment 2 eliminated the Frequency × Regularity interaction providing evidence for the modulation of sub-lexical information. These results indicate that using pseudohomophones in the Go/No-go naming task minimized information provided from sub-lexical processing and maximized information provided from the lexical system.


Subject(s)
Phonetics , Reaction Time , Reading , Semantics , Vocabulary , Female , Humans , Male , Young Adult
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