Coordinated population activity underlying texture discrimination in rat barrel cortex

Rodents can robustly distinguish fine differences in texture using their whiskers, a capacity that depends on neuronal activity in primary somatosensory “barrel” cortex. Here we explore how texture was collectively encoded by populations of three to seven neuronal clusters simultaneously recorded from barrel cortex while a rat performed a discrimination task. Each cluster corresponded to the single-unit or multiunit activity recorded at an individual electrode. To learn how the firing of different clusters combines to represent texture, we computed population activity vectors across moving time windows and extracted the signal available in the optimal linear combination of clusters. We quantified this signal using receiver operating characteristic analysis and compared it to that available in single clusters. Texture encoding was heterogeneous across neuronal clusters, and only a minority of clusters carried signals strong enough to support stimulus discrimination on their own. However, jointly recorded groups of clusters were always able to support texture discrimination at a statistically significant level, even in sessions where no individual cluster represented the stimulus. The discriminative capacity of neuronal activity was degraded when error trials were included in the data, compared to only correct trials, suggesting a link between the neuronal activity and the animal's performance. These analyses indicate that small groups of barrel cortex neurons can robustly represent texture identity through synergistic interactions, and suggest that neurons downstream to barrel cortex could extract texture identity on single trials through simple linear combination of barrel cortex responses.This work was supported by the Human Frontier Science Program (Project RG0041/2009-C); European Research Council Advanced Grant CONCEPT (Project 294498); European Union FET Grants BIOTACT (Project 215910), CORONET (Project 269459), and SICODE (Project 284553); the Compagnia San Paolo; Spanish Ministry of Science and Innovation Grants BFU2008-03017/BFI and Consolider CSD2007-00023 (cofunded by the European Fund for Regional Development); and Valencia Regional Government Grants PROMETEO/2011/086 and ACOMP2010/199.Peer reviewe

Assessing the responsiveness of Spanish policymakers to the priorities of their citizens

This article analyses how well Spanish political elites have responded to the issues signalled as priorities preferred by Spanish citizens from the early 1990s to the present, and to what extent the degree of correspondence between citizens" and policymakers" priorities is related to elections, type of government, issue jurisdiction and institutional friction. To measure this the authors rely on Most Important Problem surveys and several databases on laws, bills, oral questions and annual speeches, coded according to the comparative agendas project. They argue that the prioritisation of issues by political elites better matches public preferences at the agenda-setting stage than at the decisionmaking stage, and that correspondence of public and policymakers" priorities is inversely related to institutional friction. The evidence also illustrates that policymakers are more responsive to public priorities on those issues without shared jurisdiction, when the executive governs without a majority and immediately after elections

Emotion in Cervantes and Shakespeare

Early modern thought found in emotion a key to explaining human behaviour, highlighting the powerful way in which it can influence and disturb human life. Shakespeare’s and Cervantes’s treatment of emotion includes a full acknowledgement of its mental and bodily aspects and functions. But emotion rarely comes in a pure state. Character and emotion interact and their responses are often contradictory. Since emotions are sentiments that we feel and actions that we perform, it is worth inquiring into how, in Cervantes and Shakespeare, emotion affects their characters in different ways