In categorical proof theory, propositions and proofs are presented as objects and arrows in a category. It thus embodies the strong constructivist paradigms of propositions-as-types and proofs-as-constructions , which lie in the foundation of computational logic. Moreover, in the categorical setting, a third paradigm arises, not available elsewhere: logical-operations-as-adjunctions. It ooers a...

Event memories are stored in hippocampal-cortical networks. In this issue of Neuron, two studies, Cowansage et al. (2014) and Tanaka et al. (2014), tag active cells during memory encoding and optogenetically manipulate the activity of these "engram" cells during subsequent recall to reveal how hippocampal and cortical cell ensembles interact during retrieval.

Cryptography is a theory of secret functions. Category theory is a general theory of functions. Cryptography has reached a stage where its structures often take several pages to define, and its formulas sometimes run from page to page. Category theory has some complicated definitions as well, but one of its specialties is taming the flood of structure. Cryptography seems to be in need of high l...

Natural Horsemanship is popular among many amateur and professional trainers and as such, has been the subject of recent scientific enquiry. One method commonly adopted by Natural Horsemanship (NH) trainers is that of round pen training (RPT). RPT sessions are usually split into a series of bouts; each including two phases: chasing/flight and chasing offset/flight offset. However, NH training s...

In mammalian cerebrum there exist two distinct types of interneurons expressing nitric oxide synthase (NOS). Type I neurons are large in size and exhibit heavy nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) histochemical reaction, while type II cells are small with light NADPH-d reactivity. The time of origin of these cortical neurons relative to corticogenesis remains largely...