Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 72
Filtrar
Mais filtros

Bases de dados
Tipo de documento
Intervalo de ano de publicação
1.
Doc Ophthalmol ; 132(2): 83-99, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26868825

RESUMO

PURPOSE: To explore early findings that individuals with autism spectrum disorder (ASD) have reduced scotopic ERG b-wave amplitudes. METHODS: Light-adapted (LA) and dark-adapted (DA) ERGs were produced by a range of flash strengths that included and extended the ISCEV standard from two subject groups: a high-functioning ASD group N = 11 and a Control group N = 15 for DA and N = 14 for LA ERGs who were matched for mean age and range. Flash strengths ranged from DA -4.0 to 2.3 log phot cd s m(-2) and LA -0.5 to 1.0 log phot cd s m(-2), and Naka-Rushton curves were fitted to DA b-wave amplitude over the first growth limb (-4.0 to -1.0 log phot cd s m(-2)). The derived parameters (V max, K m and n) were compared between groups. Scotopic 15-Hz flicker ERGs (14.93 Hz) were recorded to 10 flash strengths presented in ascending order from -3.0 to 0.5 log Td s to assess the slow and fast rod pathways, respectively. LA 30-Hz flicker ERGs, oscillatory potentials (OPs) and the responses to prolonged 120-ms ON-OFF stimuli were also recorded. RESULTS: The ISCEV LA b-wave amplitude produced by 0.5 log phot cd s m(-2) was lower in the ASD group (p < 0.001). Repeated measures ANOVA for the LA b-wave amplitude series forming the photopic hill was significantly (p = 0.01) different between groups. No group differences were observed for the distributions of the time to peaks of LA a-wave, b-wave or the photopic negative responses (phNR) (p > 0.08) to the single flash stimuli, but there was a significant difference in the distribution for the LA b-wave amplitudes (corrected p = 0.006). The prolonged 120-ms ON responses were smaller in the ASD group (corrected p = 0.003), but the OFF response amplitude (p > 0.6) and ON and OFF times to peaks (p > 0.4) were similar between groups. The LA OPs showed an earlier bifurcation of OP2 in the younger ASD participants; however, no other differences were apparent in the OPs or 30-Hz flicker waveforms. DA b-wave amplitudes fell below the control 5th centile of the controls for some individuals including four ASD participants (36 %) at the 1.5 log phot cd s m(-2) flash strength and two (18%) ASD participants at the lower -2 log phot cd s m(-2) flash strength. However, across the 13 flash strengths, there were no significant group differences for b-wave amplitude's growth (repeated measures ANOVA p = 0.83). Nor were there any significant differences between the groups for the Naka-Rushton parameters (p > 0.09). No group differences were observed in the 15-Hz scotopic flicker phase or amplitude (p > 0.1), DA ERG a-wave amplitude or time to peak (p > 26). The DA b-wave time to peak at 0.5 log phot cd s m(-2) was longer in the ASD group (p = 0.04). CONCLUSION: Under LA conditions, the b-wave is reduced across the ASD group, along with the ON response of the prolonged flash ERG. Some ASD individuals also show subnormal DA ERG b-wave amplitudes. These exploratory findings suggest there is altered cone-ON bipolar signalling in ASD.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Retina/fisiopatologia , Adolescente , Adulto , Criança , Adaptação à Escuridão/fisiologia , Eletrorretinografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Visão Noturna/fisiologia , Estimulação Luminosa , Receptores Ionotrópicos de Glutamato/fisiologia , Receptores de Glutamato Metabotrópico/fisiologia , Células Bipolares da Retina/fisiologia , Células Fotorreceptoras Retinianas Cones/fisiologia , Adulto Jovem
2.
Memory ; 22(6): 669-78, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23815188

RESUMO

Considerable evidence suggests that the episodic memory system operates abnormally in autism spectrum disorder (ASD) whereas the functions of the semantic memory system are relatively preserved. Here we show that the same dissociation also applies to the domain of order memory. We asked adult participants to order the names of famous historical figures either according to their chronological order in history (probing semantic memory) or according to a random sequence shown once on a screen (probing episodic memory). As predicted, adults with ASD performed less well than age- and IQ-matched comparison individuals only on the episodic task. This observation is of considerable importance in the context of developmental theory because semantic and episodic order memory abilities can be dissociated in typically developing infants before they reach the age at which the behavioural markers associated with ASD are first apparent. This raises the possibility that early emerging memory abnormalities play a role in shaping the developmental trajectory of the disorder. We discuss the broader implications of this possibility and highlight the urgent need for greater scrutiny of memory competences in ASD early in development.


Assuntos
Transtornos Globais do Desenvolvimento Infantil/complicações , Transtornos da Memória/etiologia , Memória Episódica , Rememoração Mental , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nomes , Testes Neuropsicológicos , Psicometria , Semântica , Adulto Jovem
3.
Memory ; 21(2): 157-66, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22901078

RESUMO

Recent research has revealed that episodic memory (remembering past experiences) and episodic future thinking (imagining future experiences) rely on the same underlying neuro-cognitive system. Consistent with this suggestion, individuals with autism spectrum disorder (ASD) have been shown to experience difficulties in both domains. In the present study 18 adults with ASD and 18 typical adults performed sentence completion tasks assessing the ability to generate past and future events. Contrary to previous research findings, results demonstrated that adults with ASD performed at an equivalent level to typical adults when generating both past and future events; generating a higher number of specific events when recalling past (relative to simulating future) events, and a higher number of semantic associates when simulating future (relative to recalling past) events. Results are discussed with respect to methodological factors affecting task performance in ASD including the social nature of the research, the need to verbalise memories to the experimenter, and whether or not the specific memory request is explicit.


Assuntos
Transtorno Autístico/psicologia , Imaginação , Memória Episódica , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Rememoração Mental , Desempenho Psicomotor , Semântica
4.
Mol Autism ; 14(1): 2, 2023 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-36627713

RESUMO

The long-described atypicalities of memory functioning experienced by people with autism have major implications for daily living, academic learning, as well as cognitive remediation. Though behavioral studies have identified a robust profile of memory strengths and weaknesses in autism spectrum disorder (ASD), few works have attempted to establish a synthesis concerning their neural bases. In this systematic review of functional neuroimaging studies, we highlight functional brain asymmetries in three anatomical planes during memory processing between individuals with ASD and typical development. These asymmetries consist of greater activity of the left hemisphere than the right in ASD participants, of posterior brain regions-including hippocampus-rather than anterior ones, and presumably of the ventral (occipito-temporal) streams rather than the dorsal (occipito-parietal) ones. These functional alterations may be linked to atypical memory processes in ASD, including the pre-eminence of verbal over spatial information, impaired active maintenance in working memory, and preserved relational memory despite poor context processing in episodic memory.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Humanos , Transtorno Autístico/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Neuroimagem Funcional , Mapeamento Encefálico/métodos
5.
Autism Res ; 16(1): 99-105, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36317823

RESUMO

In a recent study on visual episodic memory (Desaunay, Clochon, et al., 2020), we have shown event-related potentials (ERPs) differences associated with priming (150-300 msec), familiarity (350-470 msec), and recollection (600-700 msec), in young people with autism spectrum disorders (ASD) compared with typical development (TD). To go further into the study of the processes of storage and retrieval of the memory trace, we re-analyzed Desaunay, Clochon, et al's data using time-frequency analysis, that is, event-related synchronization and desynchronization (ERS/ERD). This allows a decomposition of the spectral power within frequency bands associated with these ERPs. We focused both on the same time windows and the same regions of interest as previously published. We mainly identified, in ASD compared with TD, reduced ERS in low-frequencies (delta, theta) in early time-windows, and non-significant differences in ERD in higher frequencies (alpha, beta1) in all time-windows. Reduced ERS during recognition confirmed previously reported diminution of priming effects and difficulties in manipulation and retrieval of both semantic and episodic information. Conversely, preserved ERD corroborates a preservation of memory storage processes. These observations are consistent with a cognitive model of memory in ASD, that suggests difficulties in cognitive operations or executive demand at retrieval, subsequent to successful long-term storage of information. LAY SUMMARY: We assessed the EEG synchronization and desynchronization, during visual episodic recognition. We observed, in youth with Autism, reduced synchronization in low-frequencies (delta, theta), suggesting reduced access to and manipulation of long-term stored information. By contrast, non-significant differences in desynchronization at higher frequencies (alpha, beta frequency bands), that support long-term stored semantic and episodic information, suggested preserved memory traces.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Adolescente , Humanos , Eletroencefalografia , Sincronização Cortical , Transtorno do Espectro Autista/complicações , Memória/fisiologia
6.
Neurosci Biobehav Rev ; 154: 105430, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37871780

RESUMO

A central question in understanding cognition and pathology-related cognitive changes is how we process time. However, time processing difficulties across several neurological and psychiatric conditions remain seldom investigated. The aim of this review is to develop a unifying taxonomy of time processing, and a neuropsychological perspective on temporal difficulties. Four main temporal judgments are discussed: duration processing, simultaneity and synchrony, passage of time, and mental time travel. We present an integrated theoretical framework of timing difficulties across psychiatric and neurological conditions based on selected patient populations. This framework provides new mechanistic insights on both (a) the processes involved in each temporal judgement, and (b) temporal difficulties across pathologies. By identifying underlying transdiagnostic time-processing mechanisms, this framework opens fruitful avenues for future research.


Assuntos
Transtornos Mentais , Percepção do Tempo , Humanos , Transtornos Mentais/psicologia , Cognição , Julgamento , Percepção Auditiva
7.
Doc Ophthalmol ; 125(3): 219-27, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22918709

RESUMO

PURPOSE: Autism spectrum disorder (ASD) is a condition in which visual perception to both static and moving stimuli is altered. The aim of this study was to investigate the early cortical responses of subjects with ASD to simple patterns and moving radial rings using visual evoked potentials (VEPs). METHODS: Male ASD participants (n = 9) and typically developing (TD) individuals (n = 7) were matched for full, performance and verbal IQ (p > 0.263). VEPs were recorded to the pattern reversing checks of 50' side length presented with Michelson contrasts of 98 and 10 % and to the onset of motion-either expansion or contraction of low-contrast concentric rings (33.3 % duty cycle at 10 % contrast). RESULTS: There were no significant differences between groups in the VEPs elicited by pattern reversal checkerboards of high (98 %) or low (10 %) contrast. The ASD group had a significantly larger N160 peak (1.85 x) amplitude to motion onset VEPs elicited by the expansion of radial rings (p = 0.001). No differences were evident in contraction VEP peak amplitudes nor in the latencies of the motion onset N160 peaks. There was no evidence of a response that could be associated with adaptation to the motion stimulus in the interstimulus interval following an expansion or contraction phase of the rings. CONCLUSION: These data support a difference in processing of motion onset stimuli in this adult high-functioning ASD group compared to the TD group.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Potenciais Evocados Visuais/fisiologia , Percepção de Movimento/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Córtex Visual/fisiologia , Adulto , Sensibilidades de Contraste/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
Dev Psychopathol ; 24(1): 225-39, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22293006

RESUMO

Evidence regarding the use of inner speech by individuals with autism spectrum disorder (ASD) is equivocal. To clarify this issue, the current study employed multiple techniques and tasks used across several previous studies. In Experiment 1, participants with and without ASD showed highly similar patterns and levels of serial recall for visually presented stimuli. Both groups were significantly affected by the phonological similarity of items to be recalled, indicating that visual material was spontaneously recoded into a verbal form. Confirming that short-term memory is typically verbally mediated among the majority of people with ASD, recall performance among both groups declined substantially when inner speech use was prevented by the imposition of articulatory suppression during the presentation of stimuli. In Experiment 2, planning performance on a tower of London task was substantially detrimentally affected by articulatory suppression among comparison participants, but not among participants with ASD. This suggests that planning is not verbally mediated in ASD. It is important that the extent to which articulatory suppression affected planning among participants with ASD was uniquely associated with the degree of their observed and self-reported communication impairments. This confirms a link between interpersonal communication with others and intrapersonal communication with self as a means of higher order problem solving.


Assuntos
Síndrome de Asperger/psicologia , Transtorno Autístico/psicologia , Memória de Curto Prazo/fisiologia , Pensamento/fisiologia , Adulto , Feminino , Humanos , Masculino , Rememoração Mental/fisiologia , Pessoa de Meia-Idade , Testes Neuropsicológicos
9.
Front Psychol ; 13: 741213, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36081725

RESUMO

Background: Poor mental health is known to adversely affect functional abilities, social isolation, and quality of life (QoL). It is, therefore, crucial to consider the long-term impacts of mental health conditions as autistic adults grow older. Objectives: To explore, in a group of community-based autistic adults, the extent of: (i) autistic traits, co-occurring physical and mental health conditions; (ii) age-related differences in those conditions, and changes over time; and (iii) their impact on everyday living and QoL. Method: About Sixty-eight autistic adults (aged 19-80 years) participated in the first study (T1); 49 participants from T1 took part in a follow-up at T2 (mean retest interval 2.4 years). Standardised self-report measures of autistic traits, mental health, and QoL were completed at both time points. Results: Over two-thirds (71%) of autistic adult participants experienced at least one co-occurring condition, and over a third (37%) met the criteria for three or more co-occurring conditions. Mental and physical health difficulties were related to autistic traits and difficulties in everyday life and were consistent predictors of poor QoL at T1 and T2. Conclusion: Mental health difficulties in autism persisted into older age and did not improve over time. These findings have important implications for mental health provision for autistic adults in older age.

10.
Autism Res ; 15(9): 1609-1620, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35906845

RESUMO

Recently, we have shown that pupil dilation during a recognition memory task can serve as an index of memory retrieval difficulties in autism. At the time of publication, we were unaware of specific data-analysis methods that can be used to shed further light on the origins of such memory related pupil dilation. Specifically, by distinguishing "tonic" from "phasic" changes in pupil dilation and considering their temporal progression, it is possible to draw inferences about the functional integrity of a locus coeruleus-norepinephrine system (LC-NE) that is known to play a key role in regulating memory encoding and retrieval processes. We therefore apply these analyses to our previously published eye-tracking data of adults with ASD (N = 24) and neurotypical development (TD, N = 30) during the recognition memory task. In this re-analysis, we related pupil dilation during encoding and retrieval to recognition accuracy in a per-trial analysis of linear mixed models. In ASD, we replicated attenuated recognition accuracy, which was accompanied by attenuated pupil dilation during encoding and retrieval. Group differences in pupil dilation during retrieval occurred late during the trial (after 1.75 s) and indicated an altered top-down processing like attenuated attribution of semantic salience in response to previously encoded stimuli. In addition, only in the ASD group were higher pupil dilation during encoding and lower pupil dilation during retrieval associated with decreased recognition accuracy. This supports altered modulation of memory encoding and retrieval in ASD, with LC-NE phasic activity as promising underlying mechanism. LAY SUMMARY: We investigated the changes of pupil size during memory testing in autism spectrum disorder. Adults with ASD remembered fewer items correctly than neurotypical individuals (TD). This reduced memory was related to increased pupillary responses at study and decreased pupil dilation at test only for adults with ASD indicating a different modulation of memory by the locus coeruleus.


Assuntos
Transtorno do Espectro Autista , Adulto , Nível de Alerta/fisiologia , Transtorno do Espectro Autista/complicações , Humanos , Locus Cerúleo , Pupila/fisiologia , Reconhecimento Psicológico
11.
Autism Res ; 14(6): 1237-1251, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33570261

RESUMO

The Intra-Extra-dimensional set shift task (IEDS) is a widely used test of learning and attention, believed to be sensitive to aspects of executive function. The task proceeds through a number of stages, and it is generally claimed that patterns of errors across stages can be used to discriminate between reduced attention switching and more general reductions in rates of learning. A number of papers have used the IEDS task to argue for specific attention shifting difficulties in Autism Spectrum Disorder (ASD) and Schizophrenia, however, it remains unclear how well the IEDS really differentiates between reduced attention shifting and other causes of impaired performance. To address this issue, we introduce a simple computational model of performance in the IEDS task, designed to separate the competing effects of attention shifting and general learning rate. We fit the model to data from ASD and comparison individuals matched on age and IQ, as well as to data from four previous studies which used the IEDS task. Model fits do not show consistent evidence for reductions in attention shifting rates in ASD and Schizophrenia. Instead, we find performance is better explained by differences in learning rate, particularly from punishment, which we show correlates with IQ. We, therefore, argue that the IEDS task is not a good measure of attention shifting in clinical groups. LAY SUMMARY: The Intra-Extra-Dimensional Set shift task (IEDS) is often given to autistic individuals, who tend to make more errors relative to comparison groups. This higher error rate is taken to mean that autistic individuals struggle with attention control. Our computational model of the IEDS shows that the performance of ASD and some other clinical groups can be explained instead by differences in learning rate, rather than differences in attention control.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Esquizofrenia , Atenção , Função Executiva , Humanos
12.
Front Psychol ; 12: 622462, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33967890

RESUMO

Autism spectrum disorder (ASD) is characterized by atypical perception, including processing that is biased toward local details rather than global configurations. This bias may impact on memory. The present study examined the effect of this perception on both implicit (Experiment 1) and explicit (Experiment 2) memory in conditions that promote either local or global processing. The first experiment consisted of an object identification priming task using two distinct encoding conditions: one favoring local processing (Local condition) and the other favoring global processing (Global condition) of drawings. The second experiment focused on episodic (explicit) memory with two different cartoon recognition tasks that favored either local (i.e., processing specific details) or a global processing (i.e., processing each cartoon as a whole). In addition, all the participants underwent a general clinical cognitive assessment aimed at documenting their cognitive profile and enabling correlational analyses with experimental memory tasks. Seventeen participants with ASD and 17 typically developing (TD) controls aged from 10 to 16 years participated to the first experiment and 13 ASD matched with 13 TD participants were included for the second experiment. Experiment 1 confirmed the preservation of priming effects in ASD but, unlike the Comparison group, the ASD group did not increase his performance as controls after a globally oriented processing. Experiment 2 revealed that local processing led to difficulties in discriminating lures from targets in a recognition task when both lures and targets shared common details. The correlation analysis revealed that these difficulties were associated with processing speed and inhibition. These preliminary results suggest that natural perceptual processes oriented toward local information in ASD may impact upon their implicit memory by preventing globally oriented processing in time-limited conditions and induce confusion between explicit memories that share common details.

13.
Autism Res ; 13(4): 627-640, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31858750

RESUMO

This study investigated the pupil Old/New effect in individuals with Autism Spectrum Disorder (ASD) and typical development (TD). Participants studied verbal and visual meaningful and meaningless materials in black and white on a computer screen. Pupil sizes were measured while participants performed a Remember (episodic memory with context)/Know (semantic memory, no context) recognition memory test. ASD compared to TD individuals showed significantly reduced recognition rates for all materials. Both groups showed better memory for visual compared to verbal (picture superiority effect) and meaningful compared to meaningless materials. A pupil size ratio (pupil size for test item divided by baseline) for old (studied) and new (unstudied) materials indicated larger pupils for old compared to new materials only for the TD but not the ASD group. Pupil size in response to old versus new items was positively related to recognition accuracy, confirming that the pupil Old/New effect reflects a memory phenomenon in the ASD group. In addition, this study suggests an involvement of the noradrenergic neurotransmitter system in the abnormal hippocampal functioning in ASD. Implications of these findings, as well as their underlying neurophysiology, will be discussed in relation to current theories of memory in ASD. Autism Res 2020, 13: 627-640. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Most measures of memory in Autism Spectrum Disorder (ASD) depend on verbal answers. In addition to these verbal answers, this study measured the size of the participants' pupil in response to studied and unfamiliar materials revealing memory difficulties in ASD. Measuring pupil size works nonverbally, outside of conscious awareness and forms the basis of studies on less verbal persons with ASD. Mechanisms and brain regions underlying memory differences in ASD are discussed.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Pupila/fisiologia , Reconhecimento Psicológico/fisiologia , Estimulação Acústica/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa/métodos
14.
Autism Res ; 13(11): 1970-1984, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32926571

RESUMO

This study tested whether adults with autism spectrum disorder (ASD) show the same pattern of difficulties and absence of age-related differences in short-term memory (STM) as those that have been reported in episodic long-term memory (LTM). Fifty-three adults with ASD (age range: 25-65 years) were compared to 52 age-, biological sex-, and intelligence-matched typically developing (TD; age range: 21-67 years) adults on three STM span tasks, which tested STM performance for letters (Verbal), grid locations (Visuospatial), or letters in grid locations (Multimodal). A subsample of 34 TD and 33 ASD participants ranging in age from 25 to 64 years completed a fourth Multimodal Integration task. We also administered the Color Trails Test as a measure of executive function. ASD participants' accuracy was lower than that of the TD participants on the three span tasks (Cohen's d: 0.26-0.50). The Integration task difference was marginally significant (p = .07) but had a moderate effect size (Cohen's d = 0.50). Regression analyses confirmed reduced STM performance only for older TD participants. Analyses also indicated that executive processes played a greater role in the ASD group's performance. The demonstration of similar difficulties and age-related patterning of STM in ASD to those documented for LTM and the greater recruitment of executive processes by older ASD participants on the Integration task suggest a compensatory role of frontal processes both as a means of achieving undiminished task performance and as a possible protection against older age cognitive decline in ASD. Longitudinal research is needed to confirm this. Autism Res 2020, 13: 1970-1984. © 2020 The Authors. Autism Research published by International Society for Autism Research and Wiley Periodicals LLC. LAY SUMMARY: Little is known about short-term memory (STM) in younger and older adults with autism spectrum disorder (ASD). This study tested different kinds of STM and showed that ASD adults remembered shorter sequences of letters, crosses, or letters in grid cells less well than matched participants with typical development. However, older ASD individuals performed similarly to younger ASD individuals, nor showing the reduction in performance usually seen with older age. The data suggest that ASD individuals use different underlying mechanisms when performing the tasks and that this might help protect their memory as they grow older.


Assuntos
Transtorno do Espectro Autista , Memória de Curto Prazo , Adulto , Idoso , Transtorno do Espectro Autista/complicações , Cognição , Função Executiva , Humanos , Memória de Longo Prazo , Pessoa de Meia-Idade , Adulto Jovem
15.
Autism Res ; 13(11): 1947-1958, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32207566

RESUMO

Two experiments tested the hypothesis that a plausible contributory factor of structural language impairment in Autism Spectrum Disorder (ASD) is impaired declarative memory. We hypothesized that familiarity and recollection (subserving semantic and episodic memory, respectively) are both impaired in autistic individuals with clinically significant language impairment and learning disability (ASDLI/LD ); whereas recollection is selectively impaired in autistic individuals with typical language (ASDTL ). Teenagers with ASDLI/LD (n = 19) and primary school age children with ASDTL (n = 26) were compared with teenagers with learning disability (LD) (n = 26) without autism, and primary school aged typically developing (TD) children (n = 32). Both experiments provided strong support for the hypothesized links between declarative memory processes and lexical-semantic facets of language in the two autistic groups, but not in the TD group. Additional findings of interest were that declarative memory processes and lexical-semantic knowledge were also linked in the LD group and that the ASD groups-and to a lesser extent the LD group-may have compensated for declarative memory impairments using spared visual-perceptual abilities, a finding with potential educational implications. Relative difficulties with familiarity and recollection in ASDLI/LD and LD may help explain structural language impairment, as investigated here, but also the broader learning disabilities found in these populations. Autism Res 2020. © 2020 International Society for Autism Research, Wiley Periodicals, Inc. Autism Res 2020, 13: 1947-1958. © 2020 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Language impairment and learning disability affect 45% of the autistic population yet the factors that may be contributing to them is remarkably under-researched. To date there are no explanations of the lexical semantic (word meaning) abnormalities observed in ASD. We found that declarative memory is associated with lexical semantic knowledge in autism and learning disability but not in typical development. Difficulties with declarative memory may also be compensated for using visual-perceptual abilities by autistic and learning-disabled adolescents, which has positive implications for educationalists.


Assuntos
Transtorno do Espectro Autista , Transtornos do Desenvolvimento da Linguagem , Adolescente , Transtorno do Espectro Autista/complicações , Criança , Humanos , Deficiências da Aprendizagem , Semântica
16.
Autism Res ; 13(11): 1929-1946, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32864896

RESUMO

In the domain of memory, autism is characterized by difficulties in explicitly remembering the specific order of stimuli, whereas implicit serial order memory appears to be preserved. This pattern is of considerable interest because serial order memory is known to play a critical role in children's language development. Currently, however, few paradigms exist that can effectively probe serial order memory across heterogeneous groups of children, including those who are minimally verbal. We present two experiments, involving 39 adults (20 ASD; 19 TD) and 130 children (86 ASD; 44 TD), that address this issue using an eye-tracking paradigm, which simply required participants to "watch out for a bunny" that appeared in repeating sequences of screen locations. The adults in Experiment 1 all had normative IQs, whereas Experiment 2 included children with and without substantial language and intellectual difficulties. In both experiments gaze latencies and anticipatory fixations to the bunny indicated reliable repetition learning effects in the TD but not the ASD groups. Importantly, we were able to acquire reliable data from around half of the children with significant language impairments in Experiment 2, indicating that the paradigm can shed light on important learning processes in this underrepresented group. We discuss the implications of these findings for theories of memory in ASD as well as for the utility of eye-tracking technology to probe repetition learning effects in autism. Autism Res 2020, 13: 1929-1946. © 2020 The Authors. Autism Research published by International Society for Autism Research and Wiley Periodicals LLC. LAY SUMMARY: Remembering the specific order of stimuli plays an important role in language development and is thought to be a source of difficulty for autistic individuals. Research in this area, however, rarely includes autistic participants who are minimally verbal. Here we develop an eye-tracking paradigm that demonstrates serial order learning difficulties across the autism spectrum. We discuss the implications of these findings for our understanding of the role of memory difficulties in the varied language profiles across the autism spectrum.


Assuntos
Transtorno do Espectro Autista , Adulto , Transtorno do Espectro Autista/complicações , Criança , Tecnologia de Rastreamento Ocular , Humanos , Aprendizagem
17.
Autism Res ; 13(11): 1998-2016, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32918532

RESUMO

Behavioral data on episodic recollection in autism spectrum disorders (ASD) point limited relational memory functioning. However, the involvement of successive memory processes in the profile of episodic memory in ASD needs more study. Here, we used event-related potentials (ERP) to investigate the time course of episodic recollection with an associative recognition paradigm with picture pairs. Twenty-two participants with ASD and 32 with typical development (TD), all right-handed, were included. Behavioral results confirmed difficulties in correctly recognizing identical pairs in the ASD relative to TD group. We found an unexpected amplitude decrement on the P2 (220-270 msec) and FN400 (350-470 msec) potentials, suggesting diminished priming and familiarity effects in the ASD relative to TD group. However, ERP data revealed that the recognition of associative information relies on the same electrophysiological process (old/new effect in the 600-700-msec late positive component) in ASD participants as in TD ones, with a parietal extension in the ASD group. These results suggest that the electrophysiological processes of associative recognition are qualitatively similar in individuals with and without ASD but may differ quantitatively. This difference may be driven by the reduced early processing of picture pairs that may in turn lead to their diminished integration into the semantic memory system, being partially compensated by a greater involvement of associative memory during the recollection process. Other studies would be useful to go further in identifying these cognitive processes involved in atypical recognition in ASD and their neural substrates. Autism Res 2020, 13: 1998-2016. © 2020 International Society for Autism Research and Wiley Periodicals LLC LAY SUMMARY: We identified diminished performance on the associative recognition of picture pairs in adolescents and young adults with autism when compared to typical development. Electrophysiological data revealed qualitative similarities but quantitative differences between-group, with diminished priming and familiarity processes partially compensated by an enhanced parietal recollection process.


Assuntos
Transtorno do Espectro Autista , Adolescente , Potenciais Evocados , Humanos , Rememoração Mental , Reconhecimento Psicológico , Adulto Jovem
18.
Psychol Bull ; 146(5): 377-410, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32191044

RESUMO

To address inconsistencies in the literature on memory in autism spectrum disorder (ASD), we report the first ever meta-analysis of short-term memory (STM) and episodic long-term memory (LTM) in ASD, evaluating the effects of type of material, type of retrieval and the role of interitem relations. Analysis of 64 studies comparing individuals with ASD and typical development (TD) showed greater difficulties in ASD compared with TD individuals in STM (Hedges' g = -0.53, 95% CI [-0.90, -0.16], p = .005, I² = 96%) compared with LTM (g = -0.30, 95% CI [-0.42, -0.17], p < .00001, I² = 24%), a small difficulty in verbal LTM (g = -0.21, p = .01), contrasting with a medium difficulty for visual LTM (g = -0.41, p = .0002) in ASD compared with TD individuals. We also found a general diminution in free recall compared with cued recall and recognition (LTM, free recall: g = -0.38, p < .00001, cued recall: g = -0.08, p = .58, recognition: g = -0.15, p = .16; STM, free recall: g = -0.59, p = .004, recognition: g = -0.33, p = .07). We discuss these results in terms of their relation to semantic memory. The limited diminution in verbal LTM and preserved overall recognition and cued recall (supported retrieval) may result from a greater overlap of these tasks with semantic long-term representations which are overall preserved in ASD. By contrast, difficulties in STM or free recall may result from less overlap with the semantic system or may involve additional cognitive operations and executive demands. These findings highlight the need to support STM functioning in ASD and acknowledge the potential benefit of using verbal materials at encoding and broader forms of memory support at retrieval to enhance performance. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Memória de Longo Prazo/fisiologia , Memória de Curto Prazo/fisiologia , Rememoração Mental/fisiologia , Reconhecimento Psicológico/fisiologia , Transtorno do Espectro Autista/complicações , Disfunção Cognitiva/etiologia , Humanos
19.
Autism ; 24(4): 867-883, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32267168

RESUMO

LAY ABSTRACT: Anxiety in autism is an important target for psychological therapies because it is very common and because it significantly impacts upon quality of life and well-being. Growing evidence suggests that cognitive behaviour therapies and mindfulness-based therapies can help autistic individuals learn to manage feelings of anxiety but access to such therapies remains problematic. In the current pilot study, we examined whether existing online cognitive behaviour therapy and mindfulness-based therapy self-help tools can help reduce anxiety in autistic adults. Specifically, 35 autistic adults were asked to try either an existing online cognitive behaviour therapy (n = 16) or mindfulness-based therapy (n = 19) programme while a further 19 autistic adults served as a waitlist comparison group. A first important finding was that 23 of the 35 (66%) participants who tried the online tools completed them, suggesting that such tools are, in principle, acceptable to many autistic adults. In addition, adults in the cognitive behaviour therapy and mindfulness-based therapy conditions reported significant decreases in anxiety over 3 and to some extent also 6 months that were less apparent in the waitlist group of participants. On broader measures of mental health and well-being, the benefits of the online tools were less apparent. Overall, the results suggest that online self-help cognitive behaviour therapy and mindfulness-based therapy tools should be explored further as a means of providing cost-effective mental health support to at least those autistic individuals who can engage effectively with such online tools.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Atenção Plena , Adulto , Ansiedade/terapia , Transtorno Autístico/terapia , Cognição , Humanos , Projetos Piloto , Qualidade de Vida
20.
Neuropsychologia ; 46(9): 2336-43, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18440037

RESUMO

Since the earliest descriptions of individuals with autism spectrum disorders (ASDs) abnormalities in affective behaviours have been considered a prominent feature in their clinical manifestations. What remains unclear, however, is whether these altered emotional behaviours are a mere facet of abnormalities in socio-cognitive processes or whether they constitute a primary feature of the condition. A number of studies now indicate that emotional processing atypicalities in ASD extend to domains outside the broader context of social cognition leading us to suggest that the disorder may be characterised by basic abnormalities in how psychophysiological and cognitive emotional responses modulate one another [Gaigg, S. B. & Bowler, D. M. (2007). Differential fear conditioning in Asperger's syndrome: Implications for an amygdala theory of autism. Neuropsychologia, 45, 2125-2134]. In the current study, we show that although individuals with ASD, like typical individuals, exhibit a free recall advantage for emotionally arousing and semantically related neutral as compared to unrelated neutral words, they do not show reduced forgetting rates for arousing stimuli as do typical individuals. These observations provide further support for the view that psychophysiological emotional responses do not modulate cognitive processes normally in ASD and further implicate abnormalities of amygdala connectivity (in particular with the hippocampus) in the neuropathology underlying this disorder.


Assuntos
Afeto/fisiologia , Transtorno Autístico/fisiopatologia , Transtorno Autístico/psicologia , Idioma , Rememoração Mental/fisiologia , Retenção Psicológica/fisiologia , Adulto , Tonsila do Cerebelo/fisiopatologia , Análise de Variância , Aprendizagem por Associação/fisiologia , Estudos de Casos e Controles , Condicionamento Clássico/fisiologia , Discriminação Psicológica/fisiologia , Emoções/fisiologia , Feminino , Hipocampo/fisiopatologia , Humanos , Masculino , Testes Neuropsicológicos , Semântica , Comportamento Social , Escalas de Wechsler , Redação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA