Working Memory: Flexible but Finite

Abstract

There are inherent trade-offs between the flexibility and the capacity of working memory, or the ability to temporarily hold information "in mind." In a recent issue of Neuron, Bouchacourt and Buschman (2019) present a new model of working memory that demonstrates how coordinated activity between specialized sensory networks and flexible higher-order networks may support these competing constraints.

Figure 1.. Holding Precise Memories in Mind

(A) Working memory is how we temporarily hold information in mind. For example, while hiking, we may spot a flower that we want to identify. When we look away from the desert scene to our flower guide, we can hold a precise representation of the flower’s color in mind. (B and C) In the coordinated network model, each item is input to a separate “sensory network.” When holding just one item in mind (B), we can remember it precisely, with few errors. When storing multiple items (C), representations begin to interfere in the random network. Thick gray lines represent excitatory connections; thin gray lines represent inhibitory. Note: this figure is illustrative and does not reproduce exact model parameters.