The representations of reach endpoints in posterior parietal cortex depend on which hand does the reaching

Neurons in the parietal reach region (PRR) have been implicated in the sensory-to-motor transformation required for reaching toward visually defined targets. The neurons in each cortical hemisphere might be specifically involved in planning movements of just one limb, or the PRR might code reach endpoints generically, independent of which limb will actually move. Previous work has shown that the preferred directions of PRR neurons are similar for right and left limb movements but that the amplitude of modulation may vary greatly. We now test the hypothesis that frames of reference and eye and hand gain field modulations will, like preferred directions, be independent of which hand moves. This was not the case. Many neurons show clear differences in both the frame of reference as well as in direction and strength of gain field modulations, depending on which hand is used to reach. The results suggest that the information that is conveyed from the PRR to areas closer to the motor output (the readout from the PRR) is different for each limb and that individual PRR neurons contribute either to controlling the contralateral-limb or else bimanual-limb control.

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TMS over right posterior parietal cortex induces neglect in a scene-based frame of reference

Neuropsychologia ◽

10.1016/j.neuropsychologia.2005.10.004 ◽

2006 ◽

Vol 44 (7) ◽

pp. 1222-1229 ◽

Cited By ~ 52

Author(s):

Neil G. Muggleton ◽

Peggy Postma ◽

Karolina Moutsopoulou ◽

Ian Nimmo-Smith ◽

Anthony Marcel ◽

...

Keyword(s):

Parietal Cortex ◽

Posterior Parietal Cortex ◽

Frame Of Reference ◽

Posterior Parietal

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Ipsilateral-Dominant Control of Limb Movements in Rodent Posterior Parietal Cortex

Journal of Neuroscience ◽

10.1523/jneurosci.1584-18.2018 ◽

2018 ◽

Vol 39 (3) ◽

pp. 485-502 ◽

Cited By ~ 7

Author(s):

Shogo Soma ◽

Junichi Yoshida ◽

Shigeki Kato ◽

Yukari Takahashi ◽

Satoshi Nonomura ◽

...

Keyword(s):

Parietal Cortex ◽

Posterior Parietal Cortex ◽

Limb Movements ◽

Posterior Parietal

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A study of parietal-motor connectivity by intraoperative dual cortical stimulation

10.1101/747337 ◽

2019 ◽

Cited By ~ 2

Author(s):

Luigi Cattaneo ◽

Davide Giampiccolo ◽

Pietro Meneghelli ◽

Vincenzo Tramontano ◽

Francesco Sala

Keyword(s):

Motor Cortex ◽

Parietal Cortex ◽

Posterior Parietal Cortex ◽

Primary Motor Cortex ◽

Premotor Cortex ◽

Short Latency ◽

Motor Output ◽

Cortical Motor ◽

Sensorimotor Transformations ◽

Posterior Parietal

Abstractthe function of the primate’s posterior parietal cortex in sensorimotor transformations is well-established, though in humans its complexity is still challenging. Well-established models indicate that the posterior parietal cortex influences motor output indirectly, by means of connections to the premotor cortex, which in turn is directly connected to the motor cortex. The possibility that the posterior parietal cortex could be at the origin of direct afferents to M1 has been suggested in humans but has never been confirmed directly. In the present work we assessed during intraoperative monitoring of the corticospinal tract in brain tumour patients the existence of short-latency effects of parietal stimulation on corticospinal excitability to the upper limb. We identified several foci within the inferior parietal lobule that drove short-latency influences on cortical motor output. Active foci were distributed along the postcentral gyrus and clustered around the anterior intraparietal area and around the parietal operculum. For the first time in humans, the present data show direct evidence in favour of a distributed system of connections from the posterior parietal cortex to the ipsilateral primary motor cortex.

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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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