Evidence and implications of abnormal predictive coding in dementia
Open Access
- 8 July 2021
- journal article
- research article
- Published by Oxford University Press (OUP) in Brain
- Vol. 144 (11), 3311-3321
- https://doi.org/10.1093/brain/awab254
Abstract
The diversity of cognitive deficits and neuropathological processes associated with dementias has encouraged divergence in pathophysiological explanations of disease. Here, we review an alternative framework that emphasizes convergent critical features of cognitive pathophysiology. Rather than the loss of ‘memory centres’ or ‘language centres’, or singular neurotransmitter systems, cognitive deficits are interpreted in terms of aberrant predictive coding in hierarchical neural networks. This builds on advances in normative accounts of brain function, specifically the Bayesian integration of beliefs and sensory evidence in which hierarchical predictions and prediction errors underlie memory, perception, speech and behaviour. We describe how analogous impairments in predictive coding in parallel neurocognitive systems can generate diverse clinical phenomena, including the characteristics of dementias. The review presents evidence from behavioural and neurophysiological studies of perception, language, memory and decision-making. The reformulation of cognitive deficits in terms of predictive coding has several advantages. It brings diverse clinical phenomena into a common framework; it aligns cognitive and movement disorders; and it makes specific predictions on cognitive physiology that support translational and experimental medicine studies. The insights into complex human cognitive disorders from the predictive coding framework may therefore also inform future therapeutic strategies.Keywords
Funding Information
- Dementias Platform UK and Alzheimer’s Research UK (RG94383, RG89702)
- Wellcome Trust (103838)
- Medical Research Council (SUAG/051 G101400)
- National Institute for Health Research Cambridge Biomedical Research Centre
- Wellcome Trust (103838)
- European Union’s Horizon 2020 Research and Innovation Programme
- Marie Skłodowska-Curie (798971)
This publication has 200 references indexed in Scilit:
- Active inference, sensory attenuation and illusionsCognitive Processing, 2013
- How tightly are production and comprehension interwoven?Frontiers in Psychology, 2013
- Predictions not commands: active inference in the motor systemBrain Structure and Function, 2012
- Temporal Predictive Codes for Spoken Words in Auditory CortexCurrent Biology, 2012
- Increased fMRI signal with age in familial Alzheimer's disease mutation carriersNeurobiology of Aging, 2012
- Conduction aphasia, sensory-motor integration, and phonological short-term memory – An aggregate analysis of lesion and fMRI dataBrain and Language, 2011
- Apathy Symptom Profile and Behavioral Associations in Frontotemporal Dementia vs Dementia of Alzheimer TypeArchives of Neurology, 2009
- Neurodegenerative Diseases Target Large-Scale Human Brain NetworksNeuron, 2009
- Specific auditory memory induced by nucleus basalis stimulation depends on intrinsic acetylcholineNeurobiology of Learning and Memory, 2008
- The functional anatomy of the MMN: A DCM study of the roving paradigmNeuroImage, 2008