Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

ORCID 0000-0002-9685-4101

Date of Graduation


Document Type


Degree Name

Master of Arts (MA)


Department of Graduate Psychology


Bernice Marcopulos

Yu Bao

Kethera Fogler

David Libon


Mild cognitive impairment (MCI) is abnormal cognitive decline that may be indicative of an insidious process such as dementia. Individuals with MCI are largely independent in their daily functioning but are at risk of further decline. To more deeply understand the working memory deficits associated with age-related cognitive decline, Lamar and colleagues developed a working memory task with no discontinuation rule: the Backwards Digit Task (BDT). Prior BDT research has demonstrated that individuals with mild cognitive impairment have lower overall scores on this task, and that different subtypes of MCI are more prone to certain errors. Research has not been done to examine if individuals with different MCI subtypes perform differently on individual trials. This current study examined the variability in any- and serial-order sequencing difficulty in the 5-span BDT trials across different levels of cognitive impairment (i.e., cognitively normal, subtle cognitive impairment, amnestic MCI, and mixed/dysexecutive MCI). Results indicated that the mixed/dysexecutive MCI group had significantly lower serial-order sequencing difficulty on all trials and lower any-order sequencing difficulty on trials 15 and 17. A positive effect of education was seen on trials 15, 20, and 21 when utilizing serial-order sequencing difficulty. Furthermore, more capture and transposition errors were made in the mixed/dysexecutive MCI group. These results highlight the diagnostic utility of process approach data collection in differentiating MCI subtypes. Additional implications for future clinical practice and research are discussed.



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