Among a sample of 82 highly bicultural HIV+ Caribbean Latina/o adults, both correlational and multivariate analyses showed that higher U.S. acculturation scores were associated with better global NP, verbal fluency, and processing speed, as well as attention/working memory (at the trend level). Correlational analyses showed that lower Latina/o acculturation was associated with better executive function and learning (at the trend level), while higher Latina/o acculturation was associated with better memory performance. Multivariate analyses also showed that lower Latina/o acculturation predicted better executive function and motor function (at the trend level).
These findings were consistent with prior work highlighting the impact of acculturation on neuropsychological test performance among Latina/o adults (Arnold et al., 1994
; Coffey et al., 2005
; Rosselli & Ardila, 2003
). It is particularly notable that many of the measures associated with neuropsychological performance in this study are often considered to be “culture-free” because they are non-verbal (i.e., Digit Symbol, Symbol Search, etc.). However, they were significantly associated with acculturation.
One of the most important findings of the current study is that both
non-linguistic cultural factors were significantly associated with neuropsychological functioning among HIV+ Latina/o adults. This further reinforces the theory that the influence of acculturation extends beyond the effects of language. It is also notable that self-reported English language competence (based on AMAS subscale) was significantly associated with NP test performance. Consistent with the larger U.S. Latina/o population, 68% of our sample was U.S. born (~60% of U.S. Latinas/os are U.S.-born; Passel & Cohn, 2008
). Our participants were English-dominant and highly bicultural (i.e., endorsed high identification to and competence in both U.S. and Latina/o culture). However, self-reported language competence still exerted an independent influence on neuropsychological test performance. These findings suggest that acculturation is a critical factor for consideration in neuropsychological test performance of Latina/o individuals, even among those who are highly acculturated to U.S culture.
While language functioning may be an important, other cultural factors were also associated with NP test performance. Additionally, U.S. and Latina/o acculturation scores were associated with distinct and separate NP scores. For example, only non-linguistic factors (i.e., U.S. Cultural Competence and U.S. Cultural Identity) were associated with Attention/Working Memory. These results suggest that the effects of acculturation are not consistent across neuropsychological domains. While this inconsistency has been demonstrated in prior research with healthy Mexican and Mexican-American individuals (Arnold et al., 1994
), this is the first study to do so in a clinical, Caribbean Latina/o sample.
The associations between U.S. acculturation and performance on processing speed and attention/working memory are particularly intriguing. Some researchers contend that processing speed and attention/working memory mediate general cognitive abilities, including fluid intelligence (Jaeggi, Buschkuehl, Jonides, & Perrig, 2008
; Salthouse, 1996
). Therefore, it is possible that acculturation to U.S. culture could actually improve selective cognitive skills (i.e., processing speed and attention/working memory) that in turn could enhance more general neurocognitive abilities or fluid intelligence. It is possible that Westernized cultures (including U.S. culture), which place a strong cultural value on time and speed (Stewart & Bennett, 1991
) may actually promote faster processing speed and better performance on attention/working memory tasks (which are often timed). The associations in this study between U.S. acculturation with processing speed and attention/working memory may serve as a potential mechanism to help us understand how cultural values and/or experience might alter neuropsychological test performance. Specifically, evidence suggests that cognition is not static and that it interacts with the surrounding environment and culture (Al-Namlah, Fernyhough, Meins, 2006
; Luria, 1976
; Vygotsky, 1981
; Wertsch, 1994
). Alternatively, it is also possible that better processing speed and attention/working memory might facilitate acculturation, perhaps through more efficient or rapid processing of environmental information. This could be examined in future research by prospectively following recent immigrants and assessing their acculturation levels and NP performance longitudinally.
Prior research has shown that higher U.S. acculturation is significantly, positively associated with executive function (Arnold et al., 1994
; Boone et al., 2007
; Coffey et al., 2005
). However, this is the first study that we are aware of to report that lower Latina/o
acculturation and cultural competence are related to better
performance on measures of executive function. This finding may help to explain prior results (Rivera Mindt et al., 2008
), which found that HIV+ Latina/o adults performed significantly worse only in the domain of executive function when compared to HIV+ non-Hispanic white adults on a comprehensive neuropsychological evaluation. This also highlights the important role of culture in performance on problem solving and conceptual reasoning tests (Luria, 1976
; Vygotsky, 1981
Interestingly, we found that greater
Latina/o cultural identity was significantly associated with better memory performance. This finding contradicted our hypotheses, as well as the results reported in a previous study among Mexican/Mexican Americans, in which memory was not associated with acculturation (Arnold et al., 1994
). To our knowledge, this is first time such a finding has been reported in the literature, and its implications are unclear. More research is needed to clarify this finding.
When acculturation was examined in a series of multiple regression analyses, total U.S. acculturation significantly predicted 11–14% of the variance in global NP, verbal fluency, and processing speed. Total Latina/o acculturation predicted 8% of the variance in executive function and 6% of the variance in motor function, reaching trend level. This may be due in part to inadequate norms, to the cultural biases inherent in tests, or perhaps to the cognitive demands of shifting cultural roles. Regardless, acculturation appears to a significant contributor to neuropsychological test performance, and may be a key factor driving previously reported discrepancies in test performance between Latina/o and non-Hispanic white individuals (e.g., Rivera Mindt et al., 2008
; Wojna et al., 2006
These findings also suggest that higher U.S. acculturation is associated with better NP performance and is more salient than acculturation to the non-dominant (Latina/o) culture. This is logical given that the neuropsychological tests used in this study (and ubiquitously in the field) were developed and normed within U.S./Western majority culture. Thus, it is also not surprising that lower Latina/o acculturation, including lower Spanish language competence, was significantly correlated with worse learning and executive functioning performance (as well as motor function in the multivariate analyses). The extant literature on language functioning reports that bilingualism can sometimes cause interference since the non-active language must be suppressed (Rivera Mindt et al., 2008
). Given that our participants, on average, reported being highly fluent in both English and Spanish, their Spanish language proficiency may cause cognitive interference or competition when performing English language neuropsychological tests. For example, allocating cognitive resources to suppressing the non-active language (i.e., Spanish) may require diverting resources away from the target task. Therefore, in order to assess this more directly, future acculturation research might also examine the impact of language proficiency on neuropsychological functioning through objective language assessment.
In sum, many components of acculturation to both the dominant and non-dominant cultures—including language competence, cultural competence, and cultural identity—affect neuropsychological test performance differentially. These results support the idea that acculturation should be examined as a multidimensional construct using validated measures such as the AMAS (Zea et al., 2003
). Equally important, acculturation to the dominant U.S. culture appears to be a much stronger predictor of neuropsychological performance than Latina/o acculturation, which may reflect cultural biases in tests, and therefore may be more salient for neuropsychological test interpretation (Helms, 1992
). Our results further suggest that considering the impact of acculturation on neuropsychological test performance would likely improve interpretation of neuropsychological test results within this population. Even in our English-dominant, highly bicultural sample, acculturation scores accounted for a significant amount of the variance (11–14%) in global neuropsychological performance, verbal fluency, and processing speed, as well as trends in executive and motor function. These effects may have been even stronger in a less bicultural or less U.S. acculturated sample. Therefore, acculturation should be formally assessed and considered when working with Latina/o individuals, even those who are highly acculturated to U.S. culture.
Our study had several limitations. First, our acculturation measure relied on self-report. However, the acculturation measure used in this study is well-validated and previously published research has successfully utilized this measure with a similar patient population (Zea et al., 2003
; Zea et al., 2004
). Second, the high level of acculturation to both U.S. and Latina/o culture may have reduced the variability and restricted the range in AMAS scores, thus limiting potential associations with the neuropsychological measures. Given the relationship between acculturation and neuropsychological functioning observed in this sample, it is likely that these effects would be even stronger in less acculturated samples (as mentioned above). The relative impact of different aspects of acculturation may also vary depending on acculturation level. Third, the possible influence of substance abuse should also be considered, as this is often comorbid in HIV+ samples (Byrd et al., 2011
). Although participants who met criteria for current substance abuse disorder did not differ on AMAS or neuropsychological performance in our sample, future research should examine this more thoroughly. Finally, our analyses did not control for multiple comparisons, and therefore the possibility of type I error is inflated. Future research should explore the relationships between acculturation and neuropsychological test performance in healthy control groups, as these relationships may differ in HIV+ individuals and other clinical samples.
Furthermore, research should be extended to other neurological and medical populations, as well as other racial/ethnic groups. There is a great need for this type of research as ethnic minority populations, including Latinas/os, are at greater risk for numerous diseases and disorders that impact cognition, including HIV/AIDS. Future research should also extend the current results by exploring whether or not U.S. and Latina/o acculturation levels significantly attenuate differences observed in neuropsychological test performance between Latina/o and non-Hispanic white adults. Finally, research is also needed to replicate the current findings with regard to the relationships between executive function and memory (respectively) with Latina/o acculturation. In this regard, qualitative methods may be especially useful in order to better understand these associations.
Despite its limitations, this is the first study to systematically examine the associations between distinct facets of acculturation (to both the dominant and non-dominant culture) and neuropsychological test performance using a validated, multidimensional acculturation measure within a well-characterized, clinical (i.e., HIV+) sample of Caribbean Latina/o adults. Our findings support the importance of examining acculturation to both the dominant and non-dominant cultures using a multidimensional acculturation measure, and suggest that both linguistic and non-linguistic cultural factors have separate and distinct effects on neuropsychological functioning. It is notable that acculturation significantly impacted neuropsychological test performance even among highly bicultural (including highly U.S. acculturated) individuals. Our sample is likely to reflect the large and growing segment of the U.S. Latina/o population who identify as bicultural. Currently, research suggests that 39% of U.S. Latinas/os self-identify as bicultural (Horowitz Associates, 2011
). Therefore, our findings are more likely to be generalizable to these Latinas/os, and therefore clinically relevant for their neuropsychological assessment. Overall, this study highlights the multifaceted nature of acculturation and its relationship with neuropsychological functioning. In order to increase diagnostic accuracy and to improve the interpretation of neuropsychological test performance, our findings suggest that acculturation should be measured and considered when assessing culturally diverse individuals, particularly within clinical populations.