The interoceptive inference framework suggests that our brain continuously anticipates future states of our body and aims to avoid events that might counteract homeostasis by minimizing prediction errors through activ...
详细信息
The interoceptive inference framework suggests that our brain continuously anticipates future states of our body and aims to avoid events that might counteract homeostasis by minimizing prediction errors through active inference;e.g. appropriate actions. If predicted interoceptive models are inaccurate, behavior inconsistent with our long-term homeostatic goals may result;e.g. in failures in self-control. Using a within-subject design including an inspiratory breathing-load task to examine the prediction of aversive interoceptive perturbation and a craving-regulation for palatable foods task, we examined the relationship between self-control and aversive interoceptive predictive models. Those individuals (n = 51 healthy individuals from the general population) who were more accurate in predicting their interoceptive state with respect to anticipated versus experienced dyspnea were significantly more effective in the down-regulation of craving using negative future-thinking strategies. These individuals also scored higher on a measure of trait self-control, i.e. self-regulation to achieve long-term goals. Thus, individuals with more accurate predictive interoceptive models are better able to modulate cravings and thus exert better self-control.
Auditory verbal hallucinations (AVHs)-or hearing voices-occur in clinical and non-clinical populations, but their mechanisms remain unclear. predictive processing models of psychosis have proposed that hallucinations ...
详细信息
Auditory verbal hallucinations (AVHs)-or hearing voices-occur in clinical and non-clinical populations, but their mechanisms remain unclear. predictive processing models of psychosis have proposed that hallucinations arise from an over-weighting of prior expectations in perception. It is unknown, however, whether this reflects (i) a sensitivity to explicit modulation of prior knowledge or (ii) a pre-existing tendency to spontaneously use such knowledge in ambiguous contexts. Four experiments were conducted to examine this question in healthy participants listening to ambiguous speech stimuli. In experiments 1a (n = 60) and 1b (n = 60), participants discriminated intelligible and unintelligible sine-wave speech before and after exposure to the original language templates (i.e. a modulation of expectation). No relationship was observed between top-down modulation and two common measures of hallucination-proneness. Experiment 2 (n = 99) confirmed this pattern with a different stimulus-sine-vocoded speech (SVS)-that was designed to minimize ceiling effects in discrimination and more closely model previous top-down effects reported in psychosis. In Experiment 3 (n = 134), participants were exposed to SVS without prior knowledge that it contained speech (i.e. naive listening). AVH-proneness significantly predicted both pre-exposure identification of speech and successful recall for words hidden in SVS, indicating that participants could actually decode the hidden signal spontaneously. Altogether, these findings support a pre-existing tendency to spontaneously draw upon prior knowledge in healthy people prone to AVH, rather than a sensitivity to temporary modulations of expectation. We propose a model of clinical and non-clinical hallucinations, across auditory and visual modalities, with testable predictions for future research.
The predictive processing framework includes a broad set of ideas, which might be articulated and developed in a variety of ways, concerning how the brain may leverage predictive models when implementing perception, c...
详细信息
The predictive processing framework includes a broad set of ideas, which might be articulated and developed in a variety of ways, concerning how the brain may leverage predictive models when implementing perception, cognition, decision-making, and motor control. This article provides an up-to-date introduction to the two most influential theories within this framework: predictive coding and active inference. The first half of the paper (Sections 2-5) reviews the evolution of predictive coding, from early ideas about efficient coding in the visual system to a more general model encompassing perception, cognition, and motor control. The theory is characterized in terms of the claims it makes at Marr's computational, algorithmic, and implementation levels of description, and the conceptual and mathematical connections between predictive coding, Bayesian inference, and variational free energy (a quantity jointly evaluating model accuracy and complexity) are explored. The second half of the paper (Sections 6-8) turns to recent theories of active inference. Like predictive coding, active inference models assume that perceptual and learning processes minimize variational free energy as a means of approximating Bayesian inference in a biologically plausible manner. However, these models focus primarily on planning and decision-making processes that predictive coding models were not developed to address. Under active inference, an agent evaluates potential plans (action sequences) based on their expected free energy (a quantity that combines anticipated reward and information gain). The agent is assumed to represent the world as a partially observable Markov decision process with discrete time and discrete states. Current research applications of active inference models are described, including a range of simulation work, as well as studies fitting models to empirical data. The paper concludes by considering future research directions that will be important for further devel
We argue that prediction success maximization is a basic objective of cognition and cortex, that it is compatible with but distinct from prediction error minimization, that neither objective requires subtractive codin...
详细信息
Developmental science is increasingly interested in investigating the early ontogeny of the socalled implicit self. It is supposed to be a non-conceptual form of self including the experiences of agency and bodily own...
详细信息
Developmental science is increasingly interested in investigating the early ontogeny of the socalled implicit self. It is supposed to be a non-conceptual form of self including the experiences of agency and bodily ownership. Several theories have been proposed to account for the development of an implicit self and have inspired lines of empirical investigations. However, comparing these theories is difficult because the extent to which they rely on similar concepts is unclear, which in turn prevents systematic evaluation. This paper aims to provide an overview of currently influential theories on the development of the implicit self. It advances the debate by classifying the theories as either positing a unified implicit self, multiple implicit selves, or no self at all. The core assumptions of each theory are derived based on a comprehensive set of criteria, and evaluated using current empirical research. This overview proposes research directions that would enable further theoretical understanding of the ontogeny of the implicit self.
When we watch movies, we consider the characters' mental states in order to understand and predict the narrative. Recent work in functional magnetic resonance imaging (fMRI) uses movie-viewing paradigms to measure...
详细信息
When we watch movies, we consider the characters' mental states in order to understand and predict the narrative. Recent work in functional magnetic resonance imaging (fMRI) uses movie-viewing paradigms to measure functional responses in brain regions recruited for such mental state reasoning (the theory of mind ["ToM"] network). Here, two groups of young children (n = 30 3-4 years old, n = 26 6-7 years old) viewed a short animated movie twice while undergoing fMRI. As children get older, ToM brain regions were recruited earlier in time during the second presentation of the movie. This "narrative anticipation" effect is specific: there was no such effect in a control network of brain regions that responds just as robustly to the movie (the "Pain Matrix"). These results complement prior studies in adults that suggest that ToM brain regions play a role not just in inferring, but in actively predicting, other people's thoughts and feelings, and provide novel evidence that as children get older, their ToM brain regions increasingly make such predictions.
Research suggests that at the core of paranormal belief formation is a tendency to attribute meaning to ambiguous stimuli. But it is unclear whether this tendency reflects a difference in perceptual sensitivity or a d...
详细信息
Research suggests that at the core of paranormal belief formation is a tendency to attribute meaning to ambiguous stimuli. But it is unclear whether this tendency reflects a difference in perceptual sensitivity or a decision bias. Using a two-alternative forced choice task, we tested the relationship between paranormal belief and perceptual sensitivity. Participants were shown two stimuli presented in temporal succession. In one interval an ambiguous Mooney Face (i.e., signal) was presented, in the other interval a scrambled version of the image (i.e., noise) was presented. Participants chose in which of the two intervals the face appeared. Our results revealed that participants with stronger beliefs in paranormal phenomena were less sensitive to discriminating signal from noise. This finding builds on previous research using "yes/no" tasks, but importantly disentangles perceptual sensitivity from response bias and suggests paranormal believers perceive things differently.
作者:
Zarkali, AngelikiAdams, Rick A.Psarras, StamatiosLeyland, Louise-AnnRees, GeraintWeil, Rimona S.UCL
Dementia Res Ctr 8-11 Queen Sq London WC1N 3AR England UCL
Max Planck Ctr Computat Psychiat & Aging Res 10-12 Russell Sq London WC1B 5EH England UCL
Dept Comp Sci Gower St London WC1E 6BT England UCL
Space Syntax Lab 14 Upper Woburn Pl London WC1H 0NN England UCL
Inst Cognit Neurosci 17-19 Queen Sq London WC1N 3AR England UCL
Welcome Ctr Human Neuroimaging 12 Queen Sq London WC1N 3AR England
Hallucinations are a common and distressing feature of many psychiatric and neurodegenerative conditions. In Lewy body disease, visual hallucinations are a defining feature, associated with worse outcomes;yet their me...
详细信息
Hallucinations are a common and distressing feature of many psychiatric and neurodegenerative conditions. In Lewy body disease, visual hallucinations are a defining feature, associated with worse outcomes;yet their mechanisms remain unclear and treatment options are limited. Here, we show that hallucinations in Lewy body disease are associated with altered integration of top-down predictions with incoming sensory evidence, specifically with an increased relative weighting of prior knowledge. We tested 37 individuals with Lewy body disease, 17 habitual hallucinators and 20 without hallucinations, and 20 age-matched healthy individuals. We employed an image-based learning paradigm to test whether people with Lewy body disease and visual hallucinations show higher dependence on prior knowledge. We used two-tone images that are difficult to disambiguate without any prior information but generate a strong percept when information is provided. We measured discrimination sensitivity before and after this information was provided. We observed that in people with Lewy body disease who experience hallucinations, there was greater improvement in discrimination sensitivity after information was provided, compared to non-hallucinators and controls. This suggests that people with Lewy body disease and hallucinations place higher relative weighting on prior knowledge than those who do not hallucinate. Importantly, increased severity of visual hallucinations was associated with an increased effect of prior knowledge. Together these findings suggest that visual hallucinations in Lewy body disease are linked to a shift towards top-down influences on perception and away from sensory evidence, perhaps due to an increase in sensory noise. This provides important mechanistic insights to how hallucinations develop in Lewy body disease, with potential for revealing new therapeutic targets.
We typically distinguish between V1 as an egocentric perceptual map and the hippocampus as an allocentric cognitive map. In this article, we argue that V1 also functions as a post-perceptual egocentric cognitive map. ...
详细信息
We typically distinguish between V1 as an egocentric perceptual map and the hippocampus as an allocentric cognitive map. In this article, we argue that V1 also functions as a post-perceptual egocentric cognitive map. We argue that three well-documented functions of V1, namely (i) the estimation of distance, (ii) the estimation of size, and (iii) multisensory integration, are better understood as post-perceptual cognitive inferences. This argument has two important implications. First, we argue that V1 must function as the neural correlates of the visual perception/cognition distinction and suggest how this can be accommodated by V1's laminar structure. Second, we use this insight to propose a low-level account of visual consciousness in contrast to mid-level accounts (recurrent processing theory;integrated information theory) and higher-level accounts (higher-order thought;global workspace theory). Detection thresholds have been traditionally used to rule out such an approach, but we explain why it is a mistake to equate visibility (and therefore the presence/absence of visual experience) with detection thresholds.
暂无评论