Retrieval of memory in the pigeon by context manipulations

Abstract

In Experiment I, 12 pigeons were given eight sessions of VI single stimulus training with a color in a particular context followed by eight sessions of similar training with a line angle in another context. On the next day, half of the subjects were tested for wavelength and angularity generalization in each of the two contexts, a procedure that was thus consistent with training for one dimension and inconsistent for the other. The subjects made significantly more responses to each training stimulus under the consistent context condition, but there was no difference in absolute or relative generalization slopes. In Experiment 2, 12 pigeons were trained as in Experiment I, but during generalization testing they were exposed to both contexts sequentially. Under the consistent context condition, the subjects responded more to the two training stimuli and yielded sharper absolute and relative wavelength generalization gradients: Under the inconsistent context condition, responding to the training wavelength was substantially disrupted. Thus, under appropriate testing conditions, contextual control over both the amount and the selectivity of responding can be demonstrated.Spear (1971, 1978) has proposed that success at retrieval of a memory is a function of the extent to which the subject notices, during retention testing, ambient contextual stimuli that were present but inconsequential to the target learning task and were stored as attributes of the target memory. The role of contextual retrieval cues in human memory has frequently been demonstrated. Rand and Wapner (1967) reported that the retention of a list of nonsense syllables was better when the subject was tested in the same postural position as during original learning (i.e., standing up or lying down). Greenspoon and Ranyard (1957) found that the color and location of the experimental room functioned as retrieval cues in a similar manner.A typical example from the animal memory literature is a proactive interference (PI) experiment reo ported by Spear (1971). Rats trained on a passive avoidance task followed by an active avoidance task typically showed recency in a delayed test, behaving in accordance with the active avoidance contingency.

Sensitization to apomorphine in pigeons: unaffected by latent inhibition but still due to classical conditioning

“…This phenomenon would provide the basis for a state-dependent learning effect, in the sense that the LI acquired in the undrugged state could not be retrieved while under the influence of the drug (Mackintosh 1974;Overton 1991). This state-dependent retrieval can be considered as a special instance of the more general phenomenon that the ready recall of a given memory content is substantially dependant on the precise reinstatement of the corresponding conditioning context (Thomas and McKelvie 1982;Bouton 1993;McLaren et al 1994).…”

The influence of olfactory context on Pavlovian conditioning and its expression in preweanling (16-day-old) and adult rats

“…Third, contextual influences on learning and memory constitute a significant area of study. Yet despite substantial analytical advances in other respects (Bouton & King, 1986;Bouton & Swartzentruber, 1986;Gordon, 1983;Thomas & McKelvie, 1982;Thomas, McKelvie, & Mah, 1986;Thomas, McKelvie, Ranney, & Moye, 1981), the probable dependence of such contextual influences on individual differences such as those associated with ontogeny has been largely ignored (for reviews, see Balsam & Tomie, 1985;Spear, 1978Spear, , 1981.…”

Exemplar Learning and Schematization in Language Development

“…Expressed as a "relative gradient," generalization between the training and test stimulus increased somewhat with a context change, even in the absence of an explicit perceptual learning manipulation. These results conceptually are the same as those found by Thomas and McKelvie (1982) who showed, in a completely within-subjects design with pigeons (Thomas and McKelvie 1982, Experiment 2), that generalization of responding to a particularly colored disk also increased with a context change when responding to the test stimulus was expressed relative to the training stimulus. …”

“…Accordingly, the passage of time between training and testing has been shown to increase generalization in many cases, though the effect is slight (see Bouton et al 1999, for review). Most often, what occurs in these tests is what was observed by Thomas and McKelvie (1982) with a physical context change: Responding to the cue that was initially trained is reduced more than responding to the similar test cues. Thus, as a percentage of the responding elicited by the initially trained stimulus, generalization appears to have increased.…”