III. Past and future in animal life: remembering, updating and anticipation

..And suddenly the memory returns. The taste was that of the little crumb of madeline which on Sunday mornings at Cambray my aunt Leonie used to give me, dipping it first in her own cup of real of time-flower tea... Once I had recognise the test all the flowers in our garden and in M.Swann’s park, and all the water lilies on the Vivonne and the good folk of the village and their little dwellings and the parish crunch and the whole of Cambray sprang into being.

Remembrance of Things Past

By Marcel Proust

The epigraph illustrates what this mysterious storage and retrieval system that we call memory. A gap does still exist between what we call memory referring to pure private events and what we mean by memory on its relation to learning and reasoning. In recent animal studies “learning” is concisely defined as the acquisition of a skill, while “memory” is the ability to retain that skill. In this Part we will consider experimental ways to solve a problem of how animals gain new skills and “ideas” from experience, retain them over time and use for prediction of some events in the future.

For many years explorers of animal behaviour are trying to clear the question of how organisms represent the external world. In particular, it is a very intriguing problem whether animals can operate with internal representations of stimuli received earlier, or they can only react on a real thing on sight. It is intuitively clear that when a dog returns to a place where it had buried a bone, it deals with an “idea” of that bone. When leaving that bone alone, the dog could not see or smell this desirable thing, nevertheless the dog can dig the bone up many hours later. A Russian writer Anton Chekhov vividly described this in his novel Kashtanka. The dog Kashtanka “knew exactly” that there is a dry chicken pad behind a sofa in the next closed room, and she definitely intended to pick it up the first thing in the morning when her owner opens the door (Fig. III-1). Just like cognitive ethologists many years after him, the novelist used the mental state properties such as belief, desire and intention to describe dog’s mental capabilities.

Recent studies in animal social life have shown that in many species rapid learning of socially relevant information allow them not only to remember value entries over long periods of time, but also to consider the future and plan ahead (see details in Part X). Many animals adjust their foraging strategies according to circumstances so as to optimise returns and this implies that time and quantity are being calculated (Gallistel, 1990). Albeit it is still necessary to clarify the level of mental sophistication these strategic adjustments require, all these results in sum lead us away from monopolising cognitive capabilities, in particular analytical skills based on recollecting memory and prediction.

8. WHAT MEMORY IS FOR AN INTELLIGENT ANIMAL?