Neuropsychological Test Performance Among Native and Non-Native Swedes: Second Language Effects

Area of Science:

• Neuropsychology
• Psycholinguistics
• Cognitive Science

Background:

• Neuropsychological (NP) assessments are vital for evaluating cognitive function.
• The influence of bilingualism and second language acquisition on NP test performance is not fully understood.
• Accurate NP test interpretation is essential for clinical diagnosis and research.

Purpose of the Study:

• To investigate the effects of second language acquisition on neuropsychological test performance.
• To compare the NP test scores of native and non-native Swedish speakers.
• To explore factors influencing non-native speakers' NP test outcomes, including age of arrival, linguistic background, and language proficiency.

Main Methods:

• Administered a comprehensive NP test battery in Swedish to 322 healthy adults (237 native, 85 non-native Swedish speakers).
• Compared NP scores between native and non-native speakers.
• Analyzed the impact of age of arrival, majority language family of the birth country, and Swedish language proficiency (assessed via the Boston Naming Test) on NP scores in non-native speakers.

Main Results:

• Native Swedish speakers outperformed non-native speakers on NP tasks with a verbal component.
• No significant differences were observed on purely nonverbal tasks (e.g., Rey Complex Figure).
• For non-native speakers, earlier age of arrival, shared or linguistically similar language backgrounds, and higher proficiency (indicated by Boston Naming Test scores) correlated with better NP performance.

Conclusions:

• Second language effects can lead to the misclassification of non-native individuals' cognitive abilities.
• Conversational fluency may not accurately reflect language proficiency for NP testing.
• Incorporating language proficiency assessments, such as the Boston Naming Test, can enhance the interpretation of NP test results for non-native speakers.