Prospective Memory and Quality of Life in Older Adults with Autism.

Background: Prospective memory (PM) is ‘remembering-to-remember’, or remembering to do something in the future (Brandimonte et al., 1996). In neurotypically ageing (NT) adults, PM is crucial to healthy and independent ageing (d’Ydewalle et al., 2001; Henry et al., 2004) and is a significant factor in preventing age-related memory decline (Maylor, 1996), as well as being one of the most important predictors of quality of life (QoL) (Woods, 2015). PM can involve event-based (EBPM) remembering supported by external referencing cues, and time-based (TBPM) remembering which is reliant on internal self-referencing.

Limited research on PM in ASD has been conducted with children and young adults, using computerised and pseudo-naturalistic paradigms in lab settings. PM studies with ASD adults report variable difficulties in intention formation, rule adherence and everyday memory, compared to non-autistic adults (Altgassen et al., 2012; 2013; Williams et al., 2014). However, the majority of these studies combined EBPM/TBPM assessment in single tasks, involving social demands – remembering something related to someone else (e.g. experimenter), which may have disadvantaged autistic adults to a greater extent than non-autistic individuals.

Objectives: This is the first ASD-related study evaluating the role of social motivation (self-relevant vs other-relevant) in lab-based and truly naturalistic settings and age-related differences in PM, everyday functioning and QoL.

Methods: Forty-nine adults with a diagnosis of ASD and 38 NT adults in a comparison group matched on age (19-80 years) and IQ (>70, mean 115, SD 14) are involved in 4 within-group studies in this extended programme of work. Studies 1 and 2 evaluate (1) EBPM and (2) TBPM ability as separate tasks embedded in a computerised lexical decision paradigm in a lab setting. Studies 3 and 4 explore (3) EBPM and (4) TBPM for (3a, 4a) self-relevant and (3b, 4b) other-relevant tasks in a naturalistic environment, during the course of everyday activities such as participants having to remember to phone in information in a given number of days' time. QoL was measured by WHOQoL-BREF.

Results: Preliminary analyses show the ASD group made fewer accurate but slower PM responses (p<.001) under increased demands of an ongoing lexical decision task (p<.05). Moreover, PM difficulties were highly correlated with poorer physical quality of life in the ASD group (p<.001). The studies are ongoing and our full data will be available by March 2016. Our predictions are based on our recent Ageing with Autism work (Roestorf & Bowler, 2016).

We predict: (i) poorer TBPM than EBPM in all ASDs; (ii) impaired EBPM in all ASDs compared to TD comparison groups; (iii) poorer TBPM in younger ASDs compared to TDs but (iv) no differences between the older ASD-TD groups; and (v) no group differences in ‘self-relevant’ task performance, but (vi) impaired ‘other-relevant’ task performance in ASDs compared to TDs.

Conclusions: Our findings will enhance our understanding of the role of age-related differences in QoL and different types of PM autistic adults, thus informing the challenges and benefits of growing older with autism.