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1.
Autism Res ; 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38828663

RESUMEN

The visual processing differences seen in autism often impede individuals' visual perception of the social world. In particular, many autistic people exhibit poor face recognition. Here, we sought to determine whether autistic adults also show impaired perception of dyadic social interactions-a class of stimulus thought to engage face-like visual processing. Our focus was the perception of interpersonal distance. Participants completed distance change detection tasks, in which they had to make perceptual decisions about the distance between two actors. On half of the trials, participants judged whether the actors moved closer together; on the other half, whether they moved further apart. In a nonsocial control task, participants made similar judgments about two grandfather clocks. We also assessed participants' face recognition ability using standardized measures. The autistic and nonautistic observers showed similar levels of perceptual sensitivity to changes in interpersonal distance when viewing social interactions. As expected, however, the autistic observers showed clear signs of impaired face recognition. Despite putative similarities between the visual processing of faces and dyadic social interactions, our results suggest that these two facets of social vision may dissociate.

2.
PLoS Biol ; 22(6): e3002652, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38870319

RESUMEN

Difficulties in reasoning about others' mental states (i.e., mentalising/Theory of Mind) are highly prevalent among disorders featuring dopamine dysfunctions (e.g., Parkinson's disease) and significantly affect individuals' quality of life. However, due to multiple confounding factors inherent to existing patient studies, currently little is known about whether these sociocognitive symptoms originate from aberrant dopamine signalling or from psychosocial changes unrelated to dopamine. The present study, therefore, investigated the role of dopamine in modulating mentalising in a sample of healthy volunteers. We used a double-blind, placebo-controlled procedure to test the effect of the D2/D3 antagonist haloperidol on mental state attribution, using an adaptation of the Heider and Simmel (1944) animations task. On 2 separate days, once after receiving 2.5 mg haloperidol and once after receiving placebo, 33 healthy adult participants viewed and labelled short videos of 2 triangles depicting mental state (involving mentalistic interaction wherein 1 triangle intends to cause or act upon a particular mental state in the other, e.g., surprising) and non-mental state (involving reciprocal interaction without the intention to cause/act upon the other triangle's mental state, e.g., following) interactions. Using Bayesian mixed effects models, we observed that haloperidol decreased accuracy in labelling both mental and non-mental state animations. Our secondary analyses suggest that dopamine modulates inference from mental and non-mental state animations via independent mechanisms, pointing towards 2 putative pathways underlying the dopaminergic modulation of mental state attribution: action representation and a shared mechanism supporting mentalising and emotion recognition. We conclude that dopaminergic pathways impact Theory of Mind, at least indirectly. Our results have implications for the neurochemical basis of sociocognitive difficulties in patients with dopamine dysfunctions and generate new hypotheses about the specific dopamine-mediated mechanisms underlying social cognition.


Asunto(s)
Haloperidol , Receptores de Dopamina D2 , Receptores de Dopamina D3 , Humanos , Receptores de Dopamina D2/metabolismo , Masculino , Adulto , Haloperidol/farmacología , Femenino , Receptores de Dopamina D3/metabolismo , Método Doble Ciego , Adulto Joven , Teoría de la Mente , Dopamina/metabolismo , Antagonistas de Dopamina/farmacología , Mentalización
3.
Curr Biol ; 34(10): 2265-2271.e4, 2024 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-38697110

RESUMEN

Popular accounts of mind and brain propose that the brain continuously forms predictions about future sensory inputs and combines predictions with inputs to determine what we perceive.1,2,3,4,5,6 Under "predictive processing" schemes, such integration is supported by the hierarchical organization of the cortex, whereby feedback connections communicate predictions from higher-level deep layers to agranular (superficial and deep) lower-level layers.7,8,9,10 Predictions are compared with input to compute the "prediction error," which is transmitted up the hierarchy from superficial layers of lower cortical regions to the middle layers of higher areas, to update higher-level predictions until errors are reconciled.11,12,13,14,15 In the primary visual cortex (V1), predictions have thereby been proposed to influence representations in deep layers while error signals may be computed in superficial layers. Despite the framework's popularity, there is little evidence for these functional distinctions because, to our knowledge, unexpected sensory events have not previously been presented in human laminar paradigms to contrast against expected events. To this end, this 7T fMRI study contrasted V1 responses to expected (75% likely) and unexpected (25%) Gabor orientations. Multivariate decoding analyses revealed an interaction between expectation and layer, such that expected events could be decoded with comparable accuracy across layers, while unexpected events could only be decoded in superficial laminae. Although these results are in line with these accounts that have been popular for decades, such distinctions have not previously been demonstrated in humans. We discuss how both prediction and error processes may operate together to shape our unitary perceptual experiences.


Asunto(s)
Imagen por Resonancia Magnética , Humanos , Masculino , Percepción Visual/fisiología , Adulto , Femenino , Corteza Visual Primaria/fisiología , Adulto Joven , Corteza Visual/fisiología
4.
Cortex ; 170: 57-63, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38104029

Asunto(s)
Percepción , Humanos
5.
J Cogn Neurosci ; 35(7): 1133-1143, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-37083997

RESUMEN

Perceivers can use past experiences to make sense of ambiguous sensory signals. However, this may be inappropriate when the world changes and past experiences no longer predict what the future holds. Optimal learning models propose that observers decide whether to stick with or update their predictions by tracking the uncertainty or "precision" of their expectations. However, contrasting theories of prediction have argued that we are prone to misestimate uncertainty-leading to stubborn predictions that are difficult to dislodge. To compare these possibilities, we had participants learn novel perceptual predictions before using fMRI to record visual brain activity when predictive contingencies were disrupted-meaning that previously "expected" events became objectively improbable. Multivariate pattern analyses revealed that expected events continued to be decoded with greater fidelity from primary visual cortex, despite marked changes in the statistical structure of the environment, which rendered these expectations no longer valid. These results suggest that our perceptual systems do indeed form stubborn predictions even from short periods of learning-and more generally suggest that top-down expectations have the potential to help or hinder perceptual inference in bounded minds like ours.


Asunto(s)
Aprendizaje , Corteza Visual Primaria , Humanos , Imagen por Resonancia Magnética
6.
Q J Exp Psychol (Hove) ; 76(12): 2854-2864, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36872641

RESUMEN

It is often assumed that the recognition of facial expressions is impaired in autism. However, recent evidence suggests that reports of expression recognition difficulties in autistic participants may be attributable to co-occurring alexithymia-a trait associated with difficulties interpreting interoceptive and emotional states-not autism per se. Due to problems fixating on the eye-region, autistic individuals may be more reliant on information from the mouth region when judging facial expressions. As such, it may be easier to detect expression recognition deficits attributable to autism, not alexithymia, when participants are forced to base expression judgements on the eye-region alone. To test this possibility, we compared the ability of autistic participants (with and without high levels of alexithymia) and non-autistic controls to categorise facial expressions (a) when the whole face was visible, and (b) when the lower portion of the face was covered with a surgical mask. High-alexithymic autistic participants showed clear evidence of expression recognition difficulties: they correctly categorised fewer expressions than non-autistic controls. In contrast, low-alexithymic autistic participants were unimpaired relative to non-autistic controls. The same pattern of results was seen when judging masked and unmasked expression stimuli. In sum, we find no evidence for an expression recognition deficit attributable to autism, in the absence of high levels of co-occurring alexithymia, either when participants judge whole-face stimuli or just the eye-region. These findings underscore the influence of co-occurring alexithymia on expression recognition in autism.


Asunto(s)
Trastorno del Espectro Autista , Trastorno Autístico , Reconocimiento Facial , Humanos , Síntomas Afectivos/etiología , Síntomas Afectivos/psicología , Trastorno Autístico/complicaciones , Trastorno Autístico/psicología , Expresión Facial , Máscaras , Emociones
7.
Cognition ; 232: 105356, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36502600

RESUMEN

Forming expectations about what we are likely to perceive often facilitates perception. We forge such expectations on the basis of strong statistical relationships between events in our environment. However, due to our ever-changing world these relationships often subsequently degrade or even disappear, yet it is unclear how these altered statistics influence perceptual expectations. We examined this question across two studies by training participants in perfect relationships between actions (index or little finger abductions) and outcomes (clockwise or counter-clockwise gratings), before degrading the predictive relationship in a test phase - such that 'expected' events followed actions on 50-75% of trials and 'unexpected' events ensued on the remainder. Perceptual decisions about outcomes were faster and less error prone on expected than unexpected trials when predictive relationships remained high and reduced as the relationship diminished. Drift diffusion modelling indicated that these effects are explained by shifting the starting point in the evidence accumulation process as well as biasing the rate of evidence accumulation - with the former reflecting biases from statistics within the training session and the latter those of the test session. These findings demonstrate how perceptual expectations are updated as statistical certainty diminishes, with interacting influences speculatively dependent upon learning consolidation. We discuss how underlying mechanisms optimise the interaction between learning and perception - allowing our experiences to reflect a nuanced, ever-changing environment.


Asunto(s)
Aprendizaje , Motivación , Humanos
8.
Neurosci Biobehav Rev ; 145: 105012, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36565943

RESUMEN

For decades, classic theories of action control and action awareness have been built around the idea that the brain predictively 'cancels' expected action outcomes from perception. However, recent research casts doubt over this basic premise. What do these new findings mean for classic accounts of action? Should we now 'cancel' old data, theories and approaches generated under this idea? In this paper, we argue 'No'. While doubts about predictive cancellation may urge us to fundamentally rethink how predictions shape perception, the wider pyramid using these ideas to explain action control and agentic experiences can remain largely intact. Some adaptive functions assigned to predictive cancellation can be achieved through quasi-predictive processes, that influence perception without actively tracking the probabilistic structure of the environment. Other functions may rely upon truly predictive processes, but not require that these predictions cancel perception. Appreciating the role of these processes may help us to move forward in explaining how agents optimise their interactions with the external world, even if predictive cancellation is cancelled from theory.


Asunto(s)
Encéfalo , Humanos , Desempeño Psicomotor
9.
Cortex ; 155: 347-356, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36087432

RESUMEN

Healthy aging is associated with decline in social, emotion, and identity perception, which is frequently attributed to deterioration of structures involved in social inference. It is believed that this decline is unlikely to be a result of perceptual aberrations due to intact (corrected) visual acuity. Nevertheless, the present studies examine whether more particular perceptual aberrations may be present in healthy aging, that could in principle contribute to such difficulties. The present study examined the possibility that particular deficits in configural processing impair the perception of faces in healthy aging. Across two signal detection experiments, we required a group of healthy older adults and matched younger adults to detect changes in images of faces that could differ either at the local, featural level, or in configuration of these features. In support of our hypothesis, older adults were particularly impaired in detecting configural changes, relative to detecting changes in features. The impairments were found for both upright and inverted faces and were similar in a task with images of inanimate objects (houses). Drift diffusion modelling suggested that this decline related to reduced evidence accumulation rather than a tendency to make configural judgments based on less evidence. These findings indicate that domain-general problems processing configural information contribute to the difficulties with face processing in healthy aging, and may in principle contribute to a range of higher-level social difficulties - with implications also for other groups exhibiting similar patterns in perception and understanding.


Asunto(s)
Reconocimiento Facial , Envejecimiento Saludable , Anciano , Emociones , Humanos , Juicio , Reconocimiento Visual de Modelos
10.
Curr Biol ; 32(1): R13-R17, 2022 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-35015984

RESUMEN

In this My word, Press et al. tackle the 'theory crisis' in cognitive science. Using examples of good and not-so-good theoretical practice, they distinguish theories from effects, predictions, hypotheses, typologies, and frameworks in a self-help checklist of seven questions to guide theory construction, evaluation, and testing.


Asunto(s)
Conductas Relacionadas con la Salud
11.
Psychol Sci ; 33(1): 48-59, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34878943

RESUMEN

It is widely believed that predicted tactile action outcomes are perceptually attenuated. The present experiments determined whether predictive mechanisms necessarily generate attenuation or, instead, can enhance perception-as typically observed in sensory cognition domains outside of action. We manipulated probabilistic expectations in a paradigm often used to demonstrate tactile attenuation. Adult participants produced actions and subsequently rated the intensity of forces on a static finger. Experiment 1 confirmed previous findings that action outcomes are perceived less intensely than passive stimulation but demonstrated more intense perception when active finger stimulation was removed. Experiments 2 and 3 manipulated prediction explicitly and found that expected touch during action is perceived more intensely than unexpected touch. Computational modeling suggested that expectations increase the gain afforded to expected tactile signals. These findings challenge a central tenet of prominent motor control theories and demonstrate that sensorimotor predictions do not exhibit a qualitatively distinct influence on tactile perception.


Asunto(s)
Percepción del Tacto , Tacto , Adulto , Dedos , Humanos , Tacto/fisiología , Percepción del Tacto/fisiología
12.
J Exp Psychol Gen ; 150(6): 1225-1236, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33289575

RESUMEN

We predict how our actions will influence the world around us. Prevailing models in the action control literature propose that we use these predictions to suppress or "cancel" perception of expected action outcomes, to highlight more informative surprising events. However, contrasting normative Bayesian models in sensory cognition suggest that we are more, not less, likely to perceive what we expect-given that what we expect is more likely to occur. Here we adjudicated between these models by investigating how expectations influence perceptual decisions about action outcomes in a signal detection paradigm. Across three experiments, participants performed one of two manual actions that were sometimes accompanied by brief presentation of expected or unexpected visual outcomes. Contrary to dominant cancellation models but consistent with Bayesian accounts, we found that observers were biased to report the presence of expected action outcomes. There were no effects of expectation on sensitivity. Computational modeling revealed that the action-induced bias reflected a sensory bias in how evidence was accumulated rather than a baseline shift in decision circuits. Expectation effects remained in Experiments 2 and 3 when orthogonal cues indicated which finger was more likely to be probed (i.e. task-relevant). These biases toward perceiving expected action outcomes are suggestive of a mechanism that would enable generation of largely veridical representations of our actions and their consequences in an inherently uncertain sensory world. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Asunto(s)
Señales (Psicología) , Teorema de Bayes , Sesgo , Humanos , Incertidumbre
13.
Clin Nutr ESPEN ; 40: 320-326, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33183557

RESUMEN

BACKGROUND & AIMS: Prolonged temporary tube feeding places pediatric patients at risk of tube dependency. This chart audit aimed to identify current temporary tube feeding practice within an Australian tertiary hospital, risk factors of prolonged temporary tube feeding, and the likelihood of high risk patients receiving tube dependency preventative practices. METHODS: A retrospective chart audit was conducted of the medical records of 187 pediatric inpatients who had temporary feeding tubes placed in an Australian tertiary hospital between November 2014 and March 2017. Information was collected on patient demographics and tube feeding practices. The Kaplan Meier estimate, Cox regression and logistic regression were used to determine the median time until feeding tube removal, predictors of prolonged temporary tube feeding, and the relationship between these predictors and utilization of preventative practices. RESULTS: The Kaplan Meier estimate of median tube feeding duration was 6.43 months (95% CI: 5.17-7.90). Predictors of prolonged tube feeding were prematurity (p = 0.003), feeding difficulties requiring speech pathology referral (p = 0.002), and referral for long-term feeding tubes (p = 0.002). There was a low prevalence of preventative clinical practices including documentation of tube exit plans (5.3%, n = 10) and referral for long-term feeding tubes (27.3%, n = 51). Exhibiting risk factors for prolonged tube feeding did not increase the likelihood of receiving preventative clinical practices. CONCLUSIONS: The prolonged duration of temporary tube feeding within this sample highlights the need for improved utilization of tube dependency preventative practices within high risk groups.


Asunto(s)
Nutrición Enteral , Intubación Gastrointestinal , Australia/epidemiología , Niño , Humanos , Intubación Gastrointestinal/efectos adversos , Estudios Retrospectivos , Factores de Riesgo
14.
Cognition ; 205: 104429, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32949908

RESUMEN

We frequently experience feelings of agency over events we do not objectively influence - so-called 'illusions of control'. These illusions have prompted widespread claims that we can be insensitive to objective relationships between actions and outcomes, and instead rely on grandiose beliefs about our abilities. However, these illusory biases could instead arise if we are highly sensitive to action-outcome correlations, but attribute agency when such correlations emerge simply by chance. We motion-tracked participants while they made agency judgements about a cursor that could be yoked to their actions or follow an independent trajectory. A combination of signal detection analysis, reverse correlation methods and computational modelling indeed demonstrated that 'illusions' of control could emerge solely from sensitivity to spurious action-outcome correlations. Counterintuitively, this suggests that illusions of control could arise because agents have excellent insight into the relationships between actions and outcomes in a world where causal relationships are not perfectly deterministic.


Asunto(s)
Ilusiones , Deluciones , Humanos , Juicio
16.
J Exp Psychol Hum Percept Perform ; 46(7): 657-666, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32584128

RESUMEN

Research with adults suggests that we interpret the internal states of others from kinematic cues, using models calibrated to our own action experiences. Changes in action production that occur during adolescence may therefore have implications for adolescents' understanding of others. Here we examined whether, like adults, adolescents use velocity cues to determine others' emotions and whether any differences in emotion perception would be those predicted based on differences in action production. We measured preferred walking velocity in groups of early (11-12 years old), middle (13-14 years old), and late (16-18 years old) adolescents, as well as adults, and recorded their perception of happy, angry, and sad "point-light walkers." Preferred walking velocity decreased across age, and ratings of emotional stimuli with manipulated velocity demonstrated that all groups used velocity cues to determine emotion. Importantly, the relative intensity ratings of different emotions also differed across development in a manner that was predicted based on the group differences in walking velocity. Further regression analyses demonstrated that emotion perception was predicted by participants' own movement velocity, rather than age or pubertal stage per se. These results suggest that changes in action production across adolescence are indeed accompanied by corresponding changes in how emotions are perceived from velocity. These findings indicate the importance of examining differences in action production across development when interpreting differences in how individuals understand others. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Asunto(s)
Fenómenos Biomecánicos , Reconocimiento Facial , Psicología del Adolescente , Velocidad al Caminar , Adolescente , Adulto , Factores de Edad , Niño , Señales (Psicología) , Femenino , Humanos , Masculino , Desarrollo de la Personalidad
17.
Trends Cogn Sci ; 24(4): 260-261, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32160560

Asunto(s)
Aprendizaje , Humanos
18.
Trends Cogn Sci ; 24(1): 13-24, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31787500

RESUMEN

From the noisy information bombarding our senses, our brains must construct percepts that are veridical - reflecting the true state of the world - and informative - conveying what we did not already know. Influential theories suggest that both challenges are met through mechanisms that use expectations about the likely state of the world to shape perception. However, current models explaining how expectations render perception either veridical or informative are mutually incompatible. While the former propose that perceptual experiences are dominated by events we expect, the latter propose that perception of expected events is suppressed. To solve this paradox we propose a two-process model in which probabilistic knowledge initially biases perception towards what is likely and subsequently upweights events that are particularly surprising.


Asunto(s)
Encéfalo , Conocimiento , Humanos
19.
Curr Biol ; 29(15): R751-R753, 2019 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-31386853

RESUMEN

Prior knowledge shapes what we perceive. A new brain stimulation study suggests that this perceptual shaping is achieved by changes in sensory brain regions before the input arrives, with common mechanisms operating across different sensory areas.


Asunto(s)
Mapeo Encefálico , Motivación , Encéfalo
20.
J Exp Psychol Hum Percept Perform ; 45(6): 803-811, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30945906

RESUMEN

A range of processes are required for recognizing others' affective states. It is particularly important that we process the perceptual cues providing information about these states. These experiments tested the hypothesis that difficulties with affective state identification in older adults (OAs) arise, at least partly, from deficits in perceptual processing. To this end we presented "point light display" whole body stimuli to healthy OAs and comparison younger adults (YAs) in 3 signal detection experiments. We examined the ability of OAs to recognize visual bodily information-posture and kinematics-and whether impaired recognition of affective states can be explained by deficits in processing these cues. OAs exhibited reduced sensitivity to postural cues (Experiment 1) but not to kinematic cues (Experiment 2) in affectively neutral stimuli. Importantly, they also exhibited reduced sensitivity only to affective states conveyed predominantly through posture (Experiment 3) -that is, the cue they were impaired in perceiving. These findings highlight how affective state identification difficulties in OAs may arise from problems in perceptual processing and demonstrate more widely how it is essential to consider the contribution of perceptual processes to emotion recognition. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Asunto(s)
Envejecimiento/fisiología , Emociones/fisiología , Postura/fisiología , Reconocimiento en Psicología/fisiología , Percepción Social , Adulto , Anciano , Fenómenos Biomecánicos , Señales (Psicología) , Femenino , Humanos , Masculino , Adulto Joven
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