We report the results of a study to record vestibular evoked potentials (VsEPs) of cortical origin produced by impulsive acceleration (IA). In a sample of 12 healthy participants, evoked potentials recorded by 70 channel electroencephalography were obtained by IA stimulation at the nasion and compared with evoked potentials from the same stimulus applied to the forefingers. The nasion stimulation gave rise to a series of positive and negative deflections in the latency range of 26–72 ms, which were dependent on the polarity of the applied IA. In contrast, evoked potentials from the fingers were characterised by a single N50/P50 deflection at about 50 ms and were polarity invariant. Source analysis confirmed that the finger evoked potentials were somatosensory in origin, i.e. were somatosensory evoked potentials, and suggested that the nasion evoked potentials plausibly included vestibular midline and frontal sources, as well as contributions from the eyes, and thus were likely VsEPs. These results show considerable promise as a new method for assessment of the central vestibular system by means of VsEPs produced by IA applied to the head.

The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. AbstractIt is often unclear which course of action gives the best outcome. We can reduce this uncertainty by gathering more information; but gathering information always comes at a cost. For example, a sports player waiting too long to judge a ball's trajectory will run out of time to intercept it. Efficient samplers must therefore optimize a trade-off:when the costs of collecting further information exceed the expected benefits, they should stop sampling and start acting. In visually guided tasks, adults can make these trade-offs efficiently, correctly balancing any reductions in visuomotor uncertainty against cost factors associated with increased sampling. To investigate how this ability develops during childhood, we tested 6-11 year-olds, adolescents, and adults on a visual localization task in which the costs and benefits of sampling were formalized in a quantitative framework. This allowed us to compare participants to each other, and to an ideal observer who maximizes expected reward. Visual sampling became substantially more efficient between 6-11 years, converging onto adult performance in adolescence. Younger children systematically under-sampled information relative to the ideal observer and varied their sampling strategy more. Further analyses suggested that young children used a suboptimal decision rule that insufficiently accounted for the chance of task failure, in line with a late developing ability to compute with probabilities and costs. We therefore propose that late development of efficient information sampling, a crucial element of real-world decision-making under risk, may form an important component of sub-optimality in child perception, action, and decision-making.

The use of prior knowledge to guide perception is fundamental to human vision, especially under challenging viewing circumstances. Underpinning current theories of predictive coding, prior knowledge delivered to early sensory areas via cortical feedback connections can reshape perception of ambiguous stimuli, such as 'two-tone' images. Despite extensive interest and ongoing research into this process of perceptual reorganisation in the adult brain, it is not yet fully understood how or when the efficient use of prior knowledge for visual perception develops. Here we show for the first time that adult-like levels of perceptual reorganisation do not emerge until late childhood. We used a behavioural two-tone paradigm to isolate the effects of prior knowledge on visual perception in children aged 4 - 12 years and adults, and found a clear developmental progression in the perceptual benefit gained from informative cues. Whilst photo cueing reliably triggered perceptual reorganisation of two-tones for adults, 4- to 9-year-olds' performed significantly poorer immediately after cueing than within-subject benchmarks of recognition. Young childens' behaviour revealed perceptual biases towards local image features, as has been seen in image classification neural networks. We tested three such models (AlexNet, CorNet and NASNet) on two-tone classification, and while we found that network depth and recurrence may improve recognition, the best-performing network behaved similarly to young children. Our results reveal a prolonged development of prior-knowledge-guided vision throughout childhood, a process which may be central to other perceptual abilities that continue developing throughout childhood. This highlights the importance of effective reconciliation of signal and prediction for robust perception in both human and computational vision systems.

No abstract

No abstract