Rodriguez-Sanchez, Julia;
Oloye, Hope;
Martin, Ingrid M;
Hauke, Daniel J;
(2023)
Evidence for a Primary Prior Deficit as a Mechanism of Auditory Hallucinations.
The Journal of Neuroscience
, 43
(50)
pp. 8579-8581.
10.1523/JNEUROSCI.1601-23.2023.
Preview |
Text
8579.full.pdf - Published Version Download (507kB) | Preview |
Abstract
Schizophrenia is a severe mental illness characterized by hallucinations and other perceptual distortions. These symptoms are most common in the auditory domain, with ∼75% of patients with schizophrenia experiencing auditory hallucinations. They are associated with increased suicidal ideation, and they persist despite antipsychotic treatment in ∼25% of cases. Despite decades of research, our understanding of the underlying mechanisms remains limited. One possible cause of hallucinations is overreliance on prior beliefs. Indeed, it has become increasingly clear that perception, far from being a passive reception of sensory information, is a complex process influenced by our expectations, which can be formally described as Bayesian inference (Corlett et al., 2019). In Bayesian models, perceptions arise from the optimal integration of sensory evidence (likelihood), which is often noisy and ambiguous, with prior expectations (Fig. 1A). How these two sources of information are integrated is influenced by their relative precision (inverse of the variance). If prior expectations are more precise (less uncertain) than the sensory evidence, they will dominate the inference process and exert an excessive influence on perception. This occurs, for instance, when sensory input is weak: in a cloud of moving dots with low coherence of motion, the direction in which the dots are perceived to be moving will be biased by the individual's expectation. In extreme cases, this may lead to the emergence of perceptions driven by prior expectations, even in the absence of corresponding external stimuli, that is, hallucinations.
Archive Staff Only
 |
View Item |
