Forms of prediction in the nervous system

Abstract

The idea that predictions shape how we perceive and comprehend the world has become increasingly influential in the field of systems neuroscience. It also forms an important framework for understanding neuropsychiatric disorders, which are proposed to be the result of disturbances in the mechanisms through which prior information influences perception and belief, leading to the production of sub-optimal models of the world. There is a widespread tendency to conceptualize the influence of predictions exclusively in terms of 'top-down' processes, whereby predictions generated in higher-level areas exert their influence on lower-level areas within an information-processing hierarchy. However, this excludes from consideration the predictive information embedded in the 'bottom-up' stream of information processing. We describe evidence for the importance of this distinction and argue that it is critical for the development of the predictive processing framework and, ultimately, for an understanding of the perturbations that drive the emergence of neuropsychiatric symptoms and experiences.

Aberrant perceptual judgements on speech-relevant acoustic features in hallucination-prone individuals

“…In a predictive processing framework, the current results pose new evidence for changes to prior expectations in hallucination proneness 14,43 : The data support an account of an increased precision or decreased variance in individual perceptual priors 6,44 . The statistical model of single-trial confidence judgements in their own choices (“which [sound] is the more speech-like one?”) here provides important evidence.…”

Low-level, prediction-based sensory and motor processes are unimpaired in Autism

“…The predictive processing framework accounts for how we deal optimally with ambiguous signals from our environment using prediction-based optimisation of inference (Teufel and Fletcher [1], Friston and Kiebel [2]). While initially developed as a framework to understand healthy brain function, this account also offers potential insights into the processes underlying psychiatric disorders (Moore [3], Adams et al [4], Barrett et al [5], Sterzer et al [6], Gadsby and Hohwy [7], Teufel and Fletcher [8], Corlett and Fletcher [9], Friston et al [10], Kube et al [11,12], Fineberg et al [13]).…”

Predictive processing: Is the future just a memory?

“…Defining what counts as a prediction is a conceptual issue with important implications for PP and the concept of prediction has been continuously extended. For example, models of PP tended to focus on predictions conveyed by top‐down projections with inhibitory effect, suppressing predicted signals and leaving only prediction errors to go forward (Teufel & Fletcher, 2020). But this is not the only form predictions can take.…”