William Turner

All Publications

• No Evidence That Resting-State Individual Alpha Frequency Represents a Mechanism Underlying Motion-Position Illusions. The European journal of neuroscience Cottier, T., Turner, W., Chae, V. J., Holcombe, A. O., Hogendoorn, H. 2025; 62 (9): e70250

  Abstract

  Motion-position illusions (MPIs) involve the position of an object being misperceived in the context of motion (i.e., when the object contains motion, is surrounded by motion or is moving). A popular MPI is the flash-lag effect, where a static object briefly presented in spatiotemporal alignment with a moving object is perceived in a position behind the moving object. Recently, prior research has documented that there are stable individual differences in the magnitude of these illusions and possibly even their direction. To investigate the possible neural correlates of these individual differences, the present study explored whether a trait-like component of brain activity, individual alpha frequency (IAF), could predict individual illusion magnitude. Previous reports have found some correlations between IAF and perceptual tasks. Participants (N = 61) viewed the flash-lag effect (motion and luminance), Fröhlich effect, flash-drag effect, flash-grab effect, motion-induced position shift, twinkle-goes effect and the flash-jump effect. In a separate session, 5 min of eyes-closed resting state EEG data was recorded. Correlation analyses revealed no evidence for a correlation between IAF and the magnitude of any MPIs. Overall, these results suggest that IAF does not represent a mechanism underlying MPIs.

  View details for DOI 10.1111/ejn.70250

  View details for PubMedID 41178026

  View details for PubMedCentralID PMC12580576

• Rapid Reweighting of Sensory Inputs and Predictions in Visual Perception. Neural computation Turner, W., Kwon, O., Kim, M. J., Hogendoorn, H. 2025: 1-10

  Abstract

  A striking perceptual phenomenon has recently been described wherein people report seeing abrupt jumps in the location of a smoothly moving object ("position resets"). Here, we show that this phenomenon can be understood within the framework of recursive Bayesian estimation as arising from transient gain changes, temporarily prioritizing sensory input over predictive beliefs. From this perspective, position resets reveal a capacity for rapid adaptive precision weighting in human visual perception and offer a possible test bed within which to study the timing and flexibility of sensory gain control.

  View details for DOI 10.1162/neco.a.26

  View details for PubMedID 40811796

• Predictable motion is progressively extrapolated across temporally distinct processing stages in the human visual cortex. PLoS biology Turner, W., Sexton, C., Johnson, P. A., Wilson, E., Hogendoorn, H. 2025; 23 (5): e3003189

  Abstract

  Neural processing of sensory information takes time. Consequently, to estimate the current state of the world, the brain must rely on predictive processes-for example, extrapolating the motion of a ball to determine its probable present position. Some evidence implicates early (pre-cortical) processing in extrapolation, but it remains unclear whether extrapolation continues during later-stage (cortical) processing, where further delays accumulate. Moreover, the majority of such evidence relies on invasive neurophysiological techniques in animals, with accurate characterization of extrapolation effects in the human brain currently lacking. Here, we address these issues by demonstrating how precise probabilistic maps can be constructed from human EEG recordings. Participants (N = 18, two sessions) viewed a stimulus moving along a circular trajectory while EEG was recorded. Using linear discriminant analysis (LDA) classification, we extracted maps of stimulus location over time and found evidence of a forwards temporal shift occurring across temporally distinct processing stages. This accelerated emergence of position representations indicates extrapolation occurring at multiple stages of processing, with representations progressively shifted closer to real-time. We further show evidence of representational overshoot during early-stage processing following unexpected changes to an object's trajectory, and demonstrate that the observed dynamics can emerge without supervision in a simulated neural network via spike-timing-dependent plasticity.

  View details for DOI 10.1371/journal.pbio.3003189

  View details for PubMedID 40408464