College of Life and Environmental Sciences, University of Exeter, Exeter, EX1 2LU, UK.
Centre for Applied Autism Research, Department of Psychology, University of Bath, Bath, BA2 7AY, UK.
Brain. 2020 Oct 1;143(10):3151-3163. doi: 10.1093/brain/awaa243.
Autism spectrum disorder has been characterized by atypicalities in how predictions and sensory information are processed in the brain. To shed light on this relationship in the context of sensorimotor control, we assessed prediction-related measures of cognition, perception, gaze and motor functioning in a large general population (n = 92; Experiment 1) and in clinically diagnosed autistic participants (n = 29; Experiment 2). In both experiments perception and action were strongly driven by prior expectations of object weight, with large items typically predicted to weigh more than equally-weighted smaller ones. Interestingly, these predictive action models were used comparably at a sensorimotor level in both autistic and neurotypical individuals with varying levels of autistic-like traits. Specifically, initial fingertip force profiles and resulting action kinematics were both scaled according to participants' pre-lift heaviness estimates, and generic visual sampling behaviours were notably consistent across groups. These results suggest that the weighting of prior information is not chronically underweighted in autism, as proposed by simple Bayesian accounts of the disorder. Instead, our results cautiously implicate context-sensitive processing mechanisms, such as precision modulation and hierarchical volatility inference. Together, these findings present novel implications for both future scientific investigations and the autism community.
自闭症谱系障碍的特点是大脑对预测和感官信息的处理方式异常。为了在感觉运动控制的背景下阐明这种关系,我们在一个大型普通人群中(n=92;实验 1)和临床诊断的自闭症参与者中(n=29;实验 2)评估了与预测相关的认知、感知、注视和运动功能的测量值。在这两个实验中,感知和动作都受到物体重量的先前期望的强烈驱动,通常较大的物体比同等重量的较小物体预测得更重。有趣的是,这些预测动作模型在具有不同自闭症特征水平的自闭症和神经典型个体中,在感觉运动水平上被类似地使用。具体而言,初始指尖力曲线和由此产生的动作运动学都根据参与者的预提升重物估计进行了缩放,并且通用的视觉采样行为在组间明显一致。这些结果表明,简单贝叶斯模型对该疾病的预测,自闭症中先前信息的权重并不是长期被低估的。相反,我们的结果谨慎地暗示了上下文敏感的处理机制,如精度调制和分层波动性推断。这些发现共同为未来的科学研究和自闭症社区提出了新的启示。