The claim that phenotypic plasticity speeds up evolution towards a target phenotype is a recent incarnation of the Baldwin effect. To differentiate this theory from earlier interpretations of Baldwin's ideas, we name it the Baldwin expediting effect. Models that demonstrate this effect assume an extreme fitness scenario which bestows high fitness upon a single optimal phenotype and treats all o...

We postulate that a simple, three-state synaptic switch governs changes in synaptic strength at individual synapses. Under this switch rule, we show that a variety of experimental results on timing-dependent plasticity can emerge from temporal and spatial averaging over multiple synapses and multiple spike pairings. In particular, we show that a critical window for the interaction of pre- and p...

Morphine’s effects on learning and memory processes are well known to depend on synaptic plasticity in the hippocampus. Whereas the role of the hippocampus in morphine-induced amnesia and state-dependent learning is established, the biochemical and molecular mechanisms underlying these processes are poorly understood. The present study intended to investigate whether administration of morphine ...

In this article, it is demonstrated that current methods of modelling plasticity as the collective motion of discrete dislocations, such as two-dimensional discrete dislocation plasticity (DDP), are unsuitable for the simulation of very high strain rate processes (106 s−1 or more) such as plastic relaxation during shock loading. Current DDP models treat dislocations quasi-statically, ignoring t...

Introduction: Synaptic plasticity has been suggested as the primary physiological mechanism underlying memory formation. Many experimental approaches have been used to investigate whether the mechanisms underlying long-term potentiation (LTP) are activated during learning. Nevertheless, little evidence states that hippocampal-dependent learning triggers synaptic plasticity. In this study, we in...

A multiscale modeling methodology that combines the predictive capability of discrete dislocation plasticity and the computational efficiency of continuum crystal plasticity is developed. Single crystal configurations of different grain sizes modeled with periodic boundary conditions are analyzed using discrete dislocation plasticity (DD) to obtain grain size-dependent stress-strain predictions...

Correlated presynaptic and postsynaptic activity is the key factor in inducing Hebbian plasticity and memory. However, little is known about the physiological events that could mediate such coordination. Correlated cholinergic input induces spike timing-dependent plasticity-like hippocampal synaptic plasticity. Cholinergic receptors are localized to both presynaptic and postsynaptic glutamaterg...

In this work, the energetic formulation for rate-independent dissipative materials is extended to consider non-associative plasticity models. associative models, fulfilment of principle maximum dissipation naturally leads a variational evolution problem. This no longer true which are generally presented in literature non-variational form. However, recent studies have unveiled possibility recove...