Interference Control In Elderly Bilinguals: Appearances Can Be Misleading Ana Inés Ansaldo 1,2 , Ladan Ghazi-Saidi 1 , and Daniel Adrover-Roig 3 1 Centre de Recherche de l’institut Universitaire de Gériatrie de Montréal, Montreal, QC, Canada 2 École d’Orthophonie et d’Audiologie, Faculté de Médecine, Université de Montréal, Montreal, QC, Canada 3 Departamento de Pedagogía Aplicada y Psicología de la Educación, la Universidad de las Islas Baleares, Palma de Mallorca, Spain (Received 6 June 2014; accepted 18 November 2014) Bilingualism has been associated with successful aging. In particular, research on the cognitive advantages of bilingualism suggests that it can enhance control over interference and help delay the onset of dementia signs. However, the evidence on the so-called cognitive advantage is not unanimous; furthermore, little is known about the neural basis of this supposed cognitive advantage in bilingual as opposed to monolingual elderly populations. In this study, elderly bilingual and monolingual participants performed a visuospatial interference control task during functional magnetic resonance imaging (fMRI) scanning. Response times and accuracy rates were calculated for congruent and incongruent conditions of the Simon task, and the neurofunctional correlates of performance on the Simon task were examined. The results showed equivalent performance on the Simon task across groups but different underlying neural substrates in the two groups. With incongruent trials, monolinguals activated the right middle frontal gyrus, whereas bilinguals relied upon the left inferior parietal lobule. These results show that elderly bilinguals and monolinguals have equivalent interference control abilities, but relay on different neural substrates. Thus, while monolinguals show a classical PASA (posterior–anterior shift in aging) effect, recruiting frontal areas, bilinguals activate visuospatial processing alone and thus do not show this posterior–anterior shift. Moreover, a modulation of frontal activity with task-dynamic control of interference, observed in the elderly bilingual group alone, suggests that elderly bilinguals deal with interference control without recruiting a circuit that is particularly vulnerable to aging. Keywords: Bilingualism; Elderly; Executive function; Cognitive control; Neural substrate; Functional magnetic resonance imaging. The cognitive advantages of bilingualism, particu- larly lifelong bilingualism, have been the focus of many studies in recent years. While some authors report no cognitive advantages related to speaking more than one language, most agree that bilingu- alism can boost cognitive capacities in general, and executive functions in particular. Furthermore, some studies have shown that the cognitive advan- tage of bilingualism may exist regardless of confounding variables such as socioeconomic status, education, culture, immigration status, and proficiency (Bialystok & Viswanathan, 2009; de Abreu, Cruz-Santos, Tourinho, Martin, & Bialystok, 2012). Nevertheless, some authors have argued that the effect of bilingualism on cognitive reserve may be influenced by factors such as immi- gration status, education, age of onset, second lan- guage (L2) proficiency, language pairs, and frequency of language use (Guzmán-Vélez & Tranel, 2014), as well as age of acquisition of L2. For example, neurocognitive differences between early and late bilinguals represent a controversial topic in the literature on bilingualism. These differ- ences of opinion concern common (Chee, Tan, & Thiel, 1999; Klein, Milner, Zatorre, Meyer, & Evans, 1995; Perani et al., 1996; Perani et al., 1998) Address correspondence to: Ana Inés Ansaldo, Centre de Recherche de l’institut Universitaire de Gériatrie de Montréal, 4565 Queen-Mary Road, Montreal, Quebec, H3W 1W5, Canada (E-mail: ana.ines.ansaldo@umontreal.ca). Journal of Clinical and Experimental Neuropsychology, 2015 http://dx.doi.org/10.1080/13803395.2014.990359 © 2015 Taylor & Francis Downloaded by [Daniel Adrover Roig] at 04:18 07 February 2015