A novel theoretical framework for simultaneous measurement of excitatory and inhibitory conductances

The firing of neurons throughout the brain is determined by the precise relations between excitatory and inhibitory inputs, and disruption of their balance underlies many psychiatric diseases. Whether or not these inputs covary over time or between repeated stimuli remains unclear due to the lack of experimental methods for measuring both inputs simultaneously. We developed a new analytical framework for instantaneous and simultaneous measurements of both the excitatory and inhibitory neuronal inputs during a single trial under current clamp recording. This can be achieved by injecting a current composed of two high frequency sinusoidal components followed by analytical extraction of the conductances. We demonstrate the ability of this method to measure both inputs in a single trial under realistic recording constraints and from morphologically realistic CA1 pyramidal model cells. Future experimental implementation of our new method will facilitate the understanding of fundamental questions about the health and disease of the nervous system.

A novel theoretical framework for simultaneous measurement of excitatory and inhibitory conductances

Firing of neurons throughout the brain is determined by the precise relations between excitatory and inhibitory inputs and disruption of their balance underlies many psychiatric diseases. Whether or not these inputs covary over time or between repeated stimuli remains unclear due to the lack of experimental methods for measuring both inputs simultaneously. We developed a new analytical framework for instantaneous and simultaneous measurements of both the excitatory and inhibitory neuronal inputs during a single trial under current clamp recording. This can be achieved by injecting a current composed of two high frequency sinusoidal components followed by analytical extraction of the conductances. We demonstrate the ability of this method to measure both inputs in a single trial under realistic recording constraints and from morphologically realistic CA1 pyramidal model cells. Experimental implementation of our new method will facilitate the understanding of fundamental questions about the health and disease of the nervous system.

Simulations reveal how M-currents and memory-based inputs from CA3 enable single neuron mismatch detection for EC3 inputs to the CA1 subfield of hippocampus

Hippocampal region CA1 operates as an associative mismatch detector, comparing predictive signals from CA3 with signals from EC3 reflecting sensory inputs. This new CA1 pyramidal model shows that biophysical features enable these comparators to switch output between brief bursts for matches and tonic spiking for mismatches. This suggests that cognitive learning models (e.g., predictive coding) may require much less match/mismatch circuitry than commonly assumed. Additional simulations illuminate deficits seen in psychiatric disorders and drug-induced states.

Democratic Centralisms—Plural? A Comparative Analysis of Functional Communism in the French and Italian Communist Party Federations of Var and Gorizia, 1956

Democratic centralism was the Leninist-Bolshevik pyramidal model of internal organization in operation in all communist parties for most of the 20th century. Thus far, the question of whether it functioned consistently across the non-ruling parties has not been addressed explicitly or systematically. This article examines the implementation of this essential internal dynamic in a French and an Italian communist party federation in the early postwar period. Drawing on new personal testimonies from more than 50 informants, and inedita archival evidence, this analysis reveals not only similarities but also clear functional disparities between the two cases.

Strengthening Sustainability Through the Lenses of Corporate Social Responsibility Concept

The term “Corporate Social Responsibility” has gained lot of momentum in the last few decades. Carroll's pyramidal model has made significant contribution to the debate by categorizing corporate social responsibility into four broad dimensions: Economic, Legal, Ethical and Philanthropic. This paper looks into different dimensions of corporate social responsibility and tries to deconstruct its primary motive. Through the scanning of literatures on the definitions of corporate social responsibility concept, this paper tries to understand the focus of such an attempt. It then takes the help of qualitative in-depth interview methodology to understand what the corporate managers in India across sectors feel about corporate social responsibility. This leads to convergence of literature review and in-depth interview findings benefiting both academic and corporate world. The findings suggest that although companies seem to accomplish such responsibility for societal purposes, the ultimate objective is an economically viable model which leads to the sustainability of a corporate organization.