Time to rethink the neural mechanisms of learning and memory

Abstract

Most studies in the neurobiology of learning assume that the underlying learning process is a pairing – dependent change in synaptic strength that requires repeated experience of events presented in close temporal contiguity. However, much learning is rapid and does not depend on temporal contiguity which has never been precisely defined. These points are well illustrated by studies showing that temporal relationships between events are rapidly learned-even over long delays- and this knowledge governs the form and timing of behavior. The speed with which anticipatory responses emerge in conditioning paradigms is determined by the information that cues provide about the timing of rewards. The challenge for understanding the neurobiology of learning is to understand the mechanisms in the nervous system that encode information from even a single experience, the nature of the memory mechanisms that can encode quantities such as time, and how the brain can flexibly perform computations based on this information.

Learned response sequences in cerebellar Purkinje cells

“…33 for a discussion). The results are in better agreement with theories suggesting the existence of additional intracellular mechanisms for storage of temporal relations in associative learning and for response timing (34)(35)(36). However, the inadequacy of synaptic weight changes to account for temporal memory traces does not mean the learning is not synapse specific.…”

Prediction error and trace dominance determine the fate of fear memories after post-training manipulations

“…First, as previously suggested, time is encoded as a component of associative memories and critically determines the timing of conditioned responding, possibly through temporal predictions about the reinforcer onset (Savastano and Miller 1998;Gallistel and Balsam 2014). In addition, US temporal prediction-error determines the extent to which reactivation destabilizes a memory trace thus making it vulnerable to the effects of an amnestic agent (Díaz-Mataix et al 2013).…”

“…Animals are capable of learning when the US arrives based on CS duration (Savastano and Miller 1998;Balsam et al 2001;Gallistel and Balsam 2014). Indeed, temporally specific CRs have been observed in fear-potentiated startle after a single training experience (Davis et al 1989), and a similar temporal specificity as a function of training parameters has been replicated for different CRs in CFC (Bevins and Ayres 1995).The aim of Experiment 1 was to establish two different temporal predictions about US arrival, as a necessary step to test our hypotheses concerning the role of US temporal prediction error in memory destabilization-reconsolidation.…”

The necessity for the observer to examine the system from a first-person frame of reference to trace the path of generation of inner sensations

“…Even though some of these findings from certain levels can find inter-connectable explanations, several others fail. This poses tremendous challenges in solving the system 1,2 . Understanding the first-person property of perception can also influence other branches of science such as physics 3 .…”

“…Both Ervin Schrödinger and Niels Bohr knew about it very well and they have mentioned it in their papers (1,2). Recent attempts to incorporate the subject in the measurements (3) is a clear example of the need for understanding perception.…”