Cognitive and neuropsychological underpinnings of relational and conjunctive working memory binding across age

Abstract

The ability to form associations (i.e., binding) is critical for memory formation. Recent studies suggest that aging specifically affects relational binding (associating separate features) but not conjunctive binding (integrating features within an object). Possibly, this dissociation may be driven by the spatial nature of the studies so far. Alternatively, relational binding may simply require more attentional resources. We assessed relational and conjunctive binding in three age groups and we included an interfering task (i.e., an articulatory suppression task). Binding was examined in a working memory (WM) task using non-spatial features: shape and colour. Thirty-one young adults (mean age = 22.35), 30 middle-aged adults (mean age = 54.80) and 30 older adults (mean age = 70.27) performed the task. Results show an effect of type of binding and an effect of age but no interaction between type of binding and age. The interaction between type of binding and interference was significant. These results indicate that aging affects relational binding and conjunctive binding similarly. However, relational binding is more susceptible to interference than conjunctive binding, which suggests that relational binding may require more attentional resources. We suggest that a general decline in WM resources associated with frontal dysfunction underlies age-related deficits in WM binding.

Keywords:

• Working memory
• Binding
• Aging
• Relational memory

We thank Karina Burger, Lieke van Lieshout, Iris Wensink and Marloes de Jonge for their assistance in collecting the data.

This work was supported by a VIDI innovational grant from the Netherlands Organisation for Scientific Research under NWO [grant number 452-008-005], awarded to the last author. The second author is supported by Alzheimer’s Society [grant number AS-R42303]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

We thank Karina Burger, Lieke van Lieshout, Iris Wensink and Marloes de Jonge for their assistance in collecting the data.

This work was supported by a VIDI innovational grant from the Netherlands Organisation for Scientific Research under NWO [grant number 452-008-005], awarded to the last author. The second author is supported by Alzheimer’s Society [grant number AS-R42303]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.