The effects of ordinal load on incidental temporal learning

ABSTRACT

How can we grasp the temporal structure of events? A few studies have indicated that representations of temporal structure are acquired when there is an intention to learn, but not when learning is incidental. Response-to-stimulus intervals, uncorrelated temporal structures, unpredictable ordinal information, and lack of metrical organization have been pointed out as key obstacles to incidental temporal learning, but the literature includes piecemeal demonstrations of learning under all these circumstances. We suggest that the unacknowledged effects of ordinal load may help reconcile these conflicting findings, ordinal load referring to the cost of identifying the sequence of events (e.g., tones, locations) where a temporal pattern is embedded. In a first experiment, we manipulated ordinal load into simple and complex levels. Participants learned ordinal-simple sequences, despite their uncorrelated temporal structure and lack of metrical organization. They did not learn ordinal-complex sequences, even though there were no response-to-stimulus intervals nor unpredictable ordinal information. In a second experiment, we probed learning of ordinal-complex sequences with strong metrical organization, and again there was no learning. We conclude that ordinal load is a key obstacle to incidental temporal learning. Further analyses showed that the effect of ordinal load is to mask the expression of temporal knowledge, rather than to prevent learning.

KEYWORDS:

• Temporal structure
• Sequence learning
• Incidental learning
• Ordinal information
• Serial recall

Acknowledgements

We are grateful to Fredrik Ullén for the stimulating discussion on a previous version of this manuscript.

ORCID

Susana Silva http://orcid.org/0000-0003-2240-1828

Karl Magnus Petersson http://orcid.org/0000-0002-8245-0392

São Luís Castro http://orcid.org/0000-0002-1487-3596

Additional information

Funding

This work was supported by Fundação para a Ciência e a Tecnologia [grant number PTDC/PSI/66641/2006], [grant number PEst-C/PSI/IU0050/2011], [grant number PEst-OE/EQB/LA0023/2011], [grant number PEst-OE/EQB/LA0023/2013], [grant number PTDC/PSI-PCO/110734/2009], [grant number UID/BIM/04773/2013 CBMR 1334], and [grant number UID/PSI/00050/2013].