Selective attention, positive and negative priming in a sequence of dichotic listening trials

In the early years of my Ph.D., I wanted to do an ERP study of my basic primed dichotic listening paradigm. My supervisor Kenneth Hugdahl and my collaborator (and unofficial supervisor) Tom Eichele wanted me to do an ERP study of a standard dichotic listening task first, so we went ahead with that. Participants sat in a comfy chair with electrodes pasted on their scalp and did sequences of dichotic listening trials for 40 minutes. A short beep at the beginning of every trial directed attention to the left, right or both ears, then two different syllables were played at the same time, one in each ear, and the participants were to indicate what they had heard. However, when the results came in, we weren't able to make sense of the results. The EEG results didn't show the lateralized effects we had expected, and the behavioural effects of attending to the instructed side were not as clear as we had expected, so we eventually abandoned the study.

Some years later, after developing my ideas about priming using other behavioural studies, I wanted to test whether I could design a study to show both positive and negative priming effects to interact with instructed attention. I would need a largish dataset in terms of number of participants and trials order to tease out what could be rather weak effects. It then occurred to me that I already had such a dataset sitting on my hard drive, so I picked up the behavioural data from the ERP dataset, and applied analyses to it according to the new theoretical model.

The results section is somewhat complex as it tests for five different hypotheses. Basically this paper reproduces some of the effects shown in previous papers (overall inhibitory selection effects of repetition, negative priming of decreased likelihood to select a recently ignored stimulus, and priming effects interact with instructed attention), as well as showing some novel effects predicted by the model (positive priming effect of increased likelihood to select a recently attended stimulus, interaction between priming and instructed attention is demonstrated in a sequential dichotic listening task). As opposed to what competing theoretical models of priming would have predicted, the selection criteria on the prime trial did not influence the priming effect.

Sætrevik (2012) Facilitating and inhibiting effects of priming and selection criteria in a sequence of DL trials - SJoP