Control by Sample Location in Pigeons' Matching to Sample

Abstract

Three experiments assessed the impact of sample location in pigeons' matching to sample. Experiments 1 and 2 demonstrated that after line or hue identity matching was acquired to high levels of accuracy with center-key samples, varying sample location across the three keys disrupted performances. The drop in accuracy occurred following both zero-delay and simultaneous training and was mostly confined to trials in which the sample appeared on a side key. Experiment 3 attempted to diminish control by location by training birds to match samples that could appear in any location prior to center-key sample training and moving-sample testing with another set of stimuli. In testing, all birds performed accurately on center-sample trials and on side-key sample trials in which the matching choice appeared on the center key. Accuracy was below chance, however, on side-key sample trials in which the matching choice appeared on the other side key. One implication of the persistent control by sample location in the three-key paradigm is that it precludes the possibility of symmetry because symmetry tests require a change in the locations at which samples and comparisons appear.

Sample and comparison location as factors in matching acquisition, transfer, and acquired equivalence

“…These results are less surprising, however, on the assumption that in the absence of any special training (Lionello-DeNolf & Urcuioli, 2000), a visual stimulus appearing at one location is a functionally different stimulus for pigeons than the same stimulus appearing at another location (Lionello & Urcuioli, 1998). From this perspective, the left-versus right-sample contingencies for location-relevant group were not conflicting.…”

“…Previous research has shown that location is a controlling feature of the nominal conditional and discriminative stimuli in tasks such as matching-to-sample (Iversen, 1997;Iversen, Sidman, & Carrigan, 1986;Lionello & Urcuioli, 1998). For instance, Lionello and Urcuioli (1998) trained pigeons to high levels of accuracy on twosample, two-comparison matching tasks with a typical configuration of stimuli: samples on the center key and comparison stimuli on the adjacent (left and right) side keys.…”

“…For instance, Lionello and Urcuioli (1998) trained pigeons to high levels of accuracy on twosample, two-comparison matching tasks with a typical configuration of stimuli: samples on the center key and comparison stimuli on the adjacent (left and right) side keys. When pigeons were later tested with the familiar samples appearing on one or the other side key and the familiar comparisons appearing on the remaining two keys, performances were close to chance (50% accuracy).…”

INTERFERÊNCIA DE CONTROLE PELA POSIÇÃO DO ESTÍMULO EM TREINO DE DISCRIMINAÇÕES CONDICIONAIS ARBITRÁRIAS EM MACACO-PREGO (Sapajus sp.)

“…É provável que o estabelecimento de relações de controle de estímulo incoerentes com o planejamento experimental, como relatado aqui, explique boa parte dos resultados inconsistentes já obtidos em trabalhos buscando a demonstração de identidade generalizada (Iversen, 1997) e a formação de classes de equivalência em não-humanos e humanos com desenvolvimento severamente atrasado (Devany, Hayes, & Nelson, 1986;Lionello & Urcuioli, 1998;Lionello-DeNolf & Urcuioli, 2002;Sidman & cols., 1982).…”

“…A interferência do controle não programado pela posição dos estímulos já foi claramente documentada em procedimentos de treino de relações condicionais com sujeitos não-humanos (Iversen, 1997;Iversen, Sidman, & Carrigan, 1986;Lionello & Urcuioli, 1998;Sidman, 1992). Usualmente, um treino de emparelhamento ao modelo por identidade ocorre com o estímulo modelo sendo apresentado numa janela central e dois estímulos de comparação em duas janelas laterais.…”