An emergent temporal basis set robustly supports cerebellar time-series learning

Learning plays a key role in the function of many neural circuits. The cerebellum is considered a learning machine essential for time interval estimation underlying motor coordination and other behaviors. Theoretical work has proposed that the cerebellar input recipient structure, the granule cell layer (GCL), performs pattern separation of inputs that facilitates learning in Purkinje cells (P-cells). However, the relationship between input reformatting and learning outcomes has remained debated, with roles emphasized for pattern separation features from sparsification to decorrelation. We took a novel approach by training a minimalist model of the cerebellar cortex to learn complex time-series data from naturalistic inputs, in contrast to traditional classification tasks. The model robustly produced temporal basis sets from naturalistic inputs, and the resultant GCL output supported learning of temporally complex target functions. Learning favored surprisingly dense granule cell activity, yet the key statistical features in GCL population activity that drove learning differed from those seen previously for classification tasks. Moreover, different cerebellar tasks were supported by diverse pattern separation features that matched the demands of the tasks. These findings advance testable hypotheses for mechanisms of temporal basis set formation and predict that population statistics of granule cell activity may differ across cerebellar regions to support distinct behaviors.

Appraisal of Drought Indices based on Climatic Variability using DrinC Software for Potwar Region in Punjab Pakistan during 1981–2019

Drought is treated as a key natural disaster that affects numerous segments of the natural environment and economy throughout the world. Drought indices (DIs) were computed for Potwar region (PR) in Punjab-Pakistan, using DrinC software which are deciles, Standard Precipitation Index (SPI) and Reconnaissance Drought Index (RDI). Drought situation of 12, 9, 6 and 3 months was estimated on temporal basis. DIs obtained by deciles technique showed that for the last 39 years, 8-years are with drought severity in a cycle and are occurring every 2 to 7-years just the once repetitively. The RDI and SPI index showed the analogous trends as of deciles. Though, for RDI and SPI, the extremely dry and severely dry class was merely two years and rest of the drought affected years with respect to deciles were normally and intermediately dry. SPI is better as compared to deciles as the severity is better understood in the context of SPI. Regression analysis revealed that the RDI and SPI indices are mutually interrelated and if first 3 month precipitation is obtainable one can forecast yearly RDI. This investigation is valuable to devise future development plans to contest vulnerable drought incidents, its mitigation and impacts on socio-economic sectors.

A probabilistic evaluation of human activity space for proactive approach behavior of a social robot

Intelligent robot companions contribute significantly to improve the living standards of people in the modern society. Therefore, humanlike decision-making skills are sought after during the design of such robots. On the one hand, such features enable the robot to be easily handled by its human user. On the other hand, the robot will have the capability of dealing with humans without disturbing them by its behavior. Perception of Behavioral Ontology prior to an interaction is an important aspect in this regard. Furthermore, humans make an instant evaluation of task-related movements of others before approaching them. In this article, we present a mechanism to monitor how the activity space is utilized by a particular user on a temporal basis as an ontological assessment of the situation and then determine an appropriate approach behavior for a proactive robot to initiate an interaction with its user. This evaluation was then used to determine appropriate proxemic behavior to approach that person. The usage of activity space varies depending on the task of an individual. We used a probabilistic approach to find the areas that are the most and least likely to be occupied within the activity space of a particular individual during various tasks. As the robot approaches its subject after analyzing the spatial behavior of the subject within his/her activity space, spatial constraints occurred as a result of which robot’s movement could be demolished. Hence, a more socially acceptable spatial behavior could be observed from the robot. In other words, an etiquette based on approach behavior is derived considering the user’s activity space. Experiment results used to validate the system are presented, and critical observations during the study and implications are discussed.

No time to waste – How the social practices of temporal organisation change in the transition from work to retirement

In contemporary societies, chronological age is widely used as a temporal basis for regulating and organising social processes. A strong system of chrononormativity provides orientation on, for example, the appropriate time range to start working, have children, or to retire. This contribution explores the multiple temporal organisations of the life course by focussing on the transition from work to retirement as the beginning of ‘old age’. It asks how people get to become ‘old’ through temporal normalities at two scales: first, the life course scale at which temporal normalities are institutionalised; and second, the everyday life scale at which temporal normalities are routinised; and how these two scales are mutually related. The paper is structured as follows: first, I outline the implications of a practice theory perspective on time and the temporal organisation of social practices across the life course; second, I discuss two concepts in order to grasp this temporal organisation, namely chrononormativity and norma-/temporality ; third, I present empirical material on assessments of the ‘right’ timing to retire, the re-structuration of everyday time in the retirement transition, and the re-negotiation of ‘wasting time’ in retirement. Results suggest the assessment of certain practices as time ‘well spent’ or ‘wasted’. And it is exactly in this assessment that links chrononormativity to norma-/temporality in retirement: Based on an increased awareness of one’s location at the latter part of the life course, the question regarding how the (limited and decreasing) time left is spent gains a completely new significance and can, hence, become a strong marker of distinction. However, the ambivalence in participants’ account suggests a potential for ‘queering’ time and age as a set of practices that resist and destabilise temporal rhythms.

Metrical Experimentation

A fundamental characteristic of Dave Brubeck’s Time Out album is that it eschews common meter, which had long formed the temporal basis for jazz. This chapter takes stock of this central aspect of Time Out. A judicious appraisal of Brubeck’s work with unusual meters and rhythms must be informed by several considerations. First, by 1959 Brubeck had been interested in metrical experimentation for more than two decades. Second, Brubeck’s fascination with the temporal aspects of jazz continued in four additional albums during the 1960s. Finally, Brubeck’s enduring legacy rests on his unique ability to pursue this progressive musical agenda while simultaneously achieving broad popular appeal.