Common Neural Substrate for Processing Depth and Direction Signals for Reaching in the Monkey Medial Posterior Parietal Cortex

Making adaptive decisions often requires inferring unobservable states based on unreliable information. Bayesian logic prescribes that individuals form probabilistic beliefs about a state by integrating the likelihood of new evidence with their prior beliefs, but human neuroimaging studies on probability representations have not typically examined this integration process. We developed an inference fMRI task in which participants estimated the posterior probability of a hidden state while we parametrically modulated the prior probability of the state, the likelihood of the supporting evidence, and a monetary penalty for estimation inaccuracy. Consistent with a neural substrate for Bayesian integration, activation in left posterior parietal cortex tracked the estimated posterior probability of the solicited state and its components of prior probability and likelihood, all independently of expected value. This activation further reflected deviations in individual reports from objective probabilities. Thus, this region may provide a neural substrate for humans' ability to approximate Bayesian inference.

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A shared neural substrate for action verbs and observed actions in human posterior parietal cortex

Science Advances ◽

10.1126/sciadv.abb3984 ◽

2020 ◽

Vol 6 (43) ◽

pp. eabb3984

Author(s):

T. Aflalo ◽

C. Y. Zhang ◽

E. R. Rosario ◽

N. Pouratian ◽

G. A. Orban ◽

...

Keyword(s):

Parietal Cortex ◽

Posterior Parietal Cortex ◽

Visual Experience ◽

Multiple Views ◽

Statistical Sampling ◽

Cortical Areas ◽

Neural Substrate ◽

Posterior Parietal ◽

High Level ◽

Action Verbs

High-level sensory and motor cortical areas are activated when processing the meaning of language, but it is unknown whether, and how, words share a neural substrate with corresponding sensorimotor representations. We recorded from single neurons in human posterior parietal cortex (PPC) while participants viewed action verbs and corresponding action videos from multiple views. We find that PPC neurons exhibit a common neural substrate for action verbs and observed actions. Further, videos were encoded with mixtures of invariant and idiosyncratic responses across views. Action verbs elicited selective responses from a fraction of these invariant and idiosyncratic neurons, without preference, thus associating with a statistical sampling of the diverse sensory representations related to the corresponding action concept. Controls indicated that the results are not the product of visual imagery or arbitrary learned associations. Our results suggest that language may activate the consolidated visual experience of the reader.

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A shared neural substrate for action verbs and observed actions in human posterior parietal cortex

10.1101/2020.04.20.039529 ◽

2020 ◽

Cited By ~ 1

Author(s):

T. Aflalo ◽

C. Zhang ◽

E.R. Rosario ◽

N. Pouratian ◽

G.A. Orban ◽

...

Keyword(s):

Parietal Cortex ◽

Posterior Parietal Cortex ◽

Visual Experience ◽

Multiple Views ◽

Statistical Sampling ◽

Cortical Areas ◽

Neural Substrate ◽

Posterior Parietal ◽

High Level ◽

Action Verbs

AbstractHigh-level sensory and motor cortical areas are activated when processing the meaning of language, but it is unknown whether, and how, words share a neural substrate with corresponding sensorimotor representations. We recorded from single neurons in human posterior parietal cortex (PPC) while participants viewed action verbs and corresponding action videos from multiple views. We find that PPC neurons exhibit a common neural substrate for action verbs and observed actions. Further, videos were encoded with mixtures of invariant and idiosyncratic responses across views. Action verbs elicited selective responses from a fraction of these invariant and idiosyncratic neurons, without preference, thus associating with a statistical sampling of the diverse sensory representations related to the corresponding action concept. Controls indicated the results are not the product of visual imagery nor arbitrary learned associations. Our results suggest that language may activate the consolidated visual experience of the reader.

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Evidence for a Posterior Parietal Cortex Contribution to Spatial but not Temporal Numerosity Perception

Cerebral Cortex ◽

10.1093/cercor/bhy163 ◽

2018 ◽

Vol 29 (7) ◽

pp. 2965-2977 ◽

Cited By ~ 8

Author(s):

Seda Cavdaroglu ◽

André Knops

Keyword(s):

Parietal Cortex ◽

Posterior Parietal Cortex ◽

Pattern Analysis ◽

Cortical Circuits ◽

Multivoxel Pattern Analysis ◽

Differential Encoding ◽

Presentation Modes ◽

Neural Substrate ◽

Posterior Parietal ◽

Numerosity Perception

Abstract Posterior parietal cortex (PPC) is thought to encode and represent the number of objects in a visual scene (i.e., numerosity). Whether this representation is shared for simultaneous and sequential stimuli (i.e., mode independency) is debated. We tested the existence of a common neural substrate for the encoding of these modes using fMRI. While both modes elicited overlapping BOLD response in occipital areas, only simultaneous numerosities significantly activated PPC. Unique activation for sequential numerosities was found in bilateral temporal areas. Multivoxel pattern analysis revealed numerosity selectivity in PPC only for simultaneous numerosities and revealed differential encoding of presentation modes. Voxel-wise numerosity tuning functions for simultaneous numerosities in occipital and parietal ROIs revealed increasing numerosity selectivity along an occipito-to-parietal gradient. Our results suggest that the parietal cortex is involved in the extraction of spatial but not temporal numerosity and question the idea of commonly used cortical circuits for a mode-independent numerosity representation.

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Posterior parietal cortex mediates encoding processes in change blindness

PsycEXTRA Dataset ◽

10.1037/e520562012-977 ◽

2009 ◽

Author(s):

Philip Tseng ◽

Cassidy Sterling ◽

Adam Cooper ◽

Bruce Bridgeman ◽

Neil G. Muggleton ◽

...

Keyword(s):

Parietal Cortex ◽

Posterior Parietal Cortex ◽

Change Blindness ◽

Posterior Parietal

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The Grasp Cell Hypothesis: Near-miss effect points to common neurological machinery in posterior parietal cortex for controllable objects and concepts

10.31234/osf.io/4awrz ◽

2018 ◽

Author(s):

Imogen M Kruse

Keyword(s):

Parietal Cortex ◽

Posterior Parietal Cortex ◽

Near Miss ◽

Illusion Of Control ◽

Gambling Behaviour ◽

Drug Seeking ◽

Spatial Influence ◽

Reward Probability ◽

Posterior Parietal ◽

Action Value

The near-miss effect in gambling behaviour occurs when an outcome which is close to a win outcome invigorates gambling behaviour notwithstanding lack of associated reward. In this paper I postulate that the processing of concepts which are deemed controllable is rooted in neurological machinery located in the posterior parietal cortex specialised for the processing of objects which are immediately actionable or controllable because they are within reach. I theorise that the use of a common machinery facilitates spatial influence on the perception of concepts such that the win outcome which is 'almost complete' is perceived as being 'almost within reach'. The perceived realisability of the win increases subjective reward probability and the associated expected action value which impacts decision-making and behaviour. This novel hypothesis is the first to offer a neurological model which can comprehensively explain many empirical findings associated with the near-miss effect as well as other gambling phenomena such as the ‘illusion of control’. Furthermore, when extended to other compulsive behaviours such as drug addiction, the model can offer an explanation for continued drug-seeking following devaluation and for the increase in cravings in response to perceived opportunity to self-administer, neither of which can be explained by simple reinforcement models alone. This paper therefore provides an innovative and unifying perspective for the study and treatment of behavioural and substance addictions.

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