Guanghan Ma
Pronouns: he/him/his
Research Mentor(s): Jonathan Reader
Co-Presenter:
Research Mentor School/College/Department: Michigan Alzheimer’s Disease Research Center / Medicine
Presentation Date: April 20
Presentation Type: Poster
Session: Session 6 – 4:40pm – 5:30 pm
Room: League Ballroom
Authors: Guanghan Ma, Allyson Gregoire, Jonathan Reader
Presenter: 20
Abstract
Introduction: Working and episodic memory are two key components of memory related to everyday functioning and individuals who have deficits in working memory demonstrate difficulty in performing tasks which require problem solving, planning, active listening skills, and tasks involving multitasking skills (Tulsky, Carlozzi, Chiaravalloti, Beaumont, Kisala, Mungas, et al., 2014). Working memory is frequently assessed with tasks such as the backward digit span test and letter number sequencing tasks that require simultaneous storage and processing of information (Tulsky et al., 2014; Oberauer et al., 2000). Working memory predicts higher level cognitive processes such as episodic memory (Tulsky et al., 2014). Episodic memory is one’s ability to recollect past experiences based on their content, location, and temporal occurrence (Dikmen, Baur, Weintraub, Mungas, Slotkin, Beaumont, et al., 2014; Pauls, Petermann, & Lepach, 2013). Deficits in episodic memory may reduce the integrity of one’s memory leading to restricted independent living (Dikmen et al. 2014). Episodic memory is best accessed via tests that require subjects to recall details of an event or a story such as in the Craft Story 21 memory test (Craft, Newcomer, Kanne, Dagogo-Jack, Cryer, Sheline, et al., 1995). The current study seeks to understand the relationship between working and episodic memory. Methods: Subjects for this study came from the National Alzheimer’s Coordinating Center (NACC) Uniform Data Set Version 3. Inclusion criteria employed for this analysis reduced the number of eligible participants from 42,661 to 13,620. Only participants’ who completed the Craft Story 21 (Craft et al. 1995) and Digit Span Memory Test (Weintraub, Besser, Dodge, Teylan, Ferris, Goldstein, et al., 2017) at their first recorded UDS Version 3 were included. Additionally, only individuals whose primary language was English and whose cognitive status was indicated as Normal, MCI, or Dementia (N = 13,620). Participants in this analysis were predominantly White (82%) and female (58%). Mean education was approximately 16 years (SD = 2.7) and mean age of the participants was roughly 71 years (SD = 10). Performance on the Craft test is measured by the number of predetermined keywords that the participant can identify after the specific time period. In the paraphrase version of the test, participants earned a point for each reference to a keyword 20 minutes after they were told the story. Scores ranged from 0 to 25. Participants also completed the Digit Span memory test (Weintraub et al. 2017). The longest span in the backward version of the test was measured by the longest consecutive sequence of digits that the participant was able to recall in the reverse order that they heard it from the test administrator. Valid scores for this ranged from 2 to 8 consecutive digits recalled. A combination of previous research (e.g., Heaton, Taylor,& Manly, 2003; Wechsler, 2009) and a data-driven examination of preliminary correlations were used to determine the predictor and outcome variables for this study. Although both the forward and backward versions of the Digit were considered as potential candidates for the independent variable, previous research indicated that the backward Digit better assesses working memory. Furthermore, based on expert consultation, it was decided to use the longest span backwards as opposed to the total number of correct digits recalled (personal communication, Dr. Bruno Giordani, February, 2022). Linear regression was used to determine the predictive ability of total story units recalled on the longest backwards span. Results: Results from the linear regression suggest that the longest backwards digit span significantly predicts participants’ scores on the paraphrased story recall (Beta = 0.05; p < 0.05). Age, years of education, and race were also significant predictors (all ps < 0.05). Discussion: Results from this study confirm prior evidence indicating that decline in working memory would be reflected in higher forms of memory such as episodic memory (Tulsky et al., 2014; Dikmen et al. 2014). If an individual has impaired working memory, it would be important for them to receive appropriate assistance with tasks that utilize both working and episodic memory. Limitations of the current study include a largely white, female, and well-educated sample. Thus, findings may not be as applicable to minority individuals or those with lower education. Interestingly, the current study did not find gender differences in working memory as expected based on prior research (Pauls et al., 2013). This could be due to a large difference in age range between the two studies. Future research may want to include a larger age range than the current investigation to assess change over time as well as the interaction between Digit Span scores and cognitive status (e.g., normal, mild cognitive impairment, demented). Presentation link
Biomedical Sciences, Engineering
