The role of the reference point and subjective age in metamemory for prospective memory

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This short questionnaire checks that the following inclusion criteria are met:

• Being aged 18-30 years or 65+ years;
• Speaking English as first language;
• Not having received a diagnosis of neurological or psychological condition (for example, depression, stroke, dementia, etc).

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Participants not meeting the inclusion criteria as in Initial_Questionnaire were excluded.

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Participants received instructions for the lexical decision task and completed a first short practice phase (5 words and 5 nonwords) where they received feedback on whether their response was correct or incorrect and were asked to repeat any incorrect trial. Participants then completed a second practice phase with 25 words and 25 nonwords, where they did not receive any feedback.

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Participants who did not reach 75% accuracy in the second practice phase of Lexical_Decision_Task_practice were excluded.

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This is a lexical-decision task. Participants were presented with strings of letters, one at the time, and asked to indicate whether they think it is a real word or a non-word.

The words were taken from the English Lexicon Project (Balota et al., 2007). The words were transformed into nonwords by changing one vowel within a letter string.

Balota, D. A., Yap, M. J., Hutchison, K. A., Cortese, M. J., Kessler, B., Loftis, B., Neely, J. H., Nelson, D. L., Simpson, G. B., & Treiman, R. (2007). The English Lexicon Project. Behavior Research Methods, 39(3), 445–459.

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Participants practiced the PM task

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Before completing the PM task, participants in the peers condition were asked to estimate a) how well other people of their age would perform at the PM task, and b) how well they would perform at the PM task.

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Before completing the PM task, participants in the performance condition were asked to estimate how well they thought they would perform at the PM task.

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Participants in the control group were not asked to produce any metacognitive rating.

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The Shipley Institute of Living Scale: Vocabulary administered as delay task.

Shipley, W. C., & Burlingame, C. C. (1941). A Conveninent Self-Administering Scale for Measuring Intellectual Impairment in Psychotics. American Journal of Psychiatry, 97(6), 1313–1325. https://doi.org/10.1176/ajp.97.6.1313

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The ongoing task consisted of a lexical-decision task. Participants were presented with strings of letters, one at the time, and asked to indicate whether they thought it was a real word or a non-word. For the PM task, participants learned a target syllable and were asked to press a different key on the keyboard whenever they detected a word containing the learned syllable.

The PM targets were 10 words containing the syllable ‘ING’, which were presented as 34th, 67th, 100th, 133rd, 166th, and 199th words.

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At the end of the PM task, participants in the peers condition were asked to provide a postdicted score for a) how well they thought other people of their age performed and b) how well they thought they performed.

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At the end of the PM task, participants in the performance condition were asked to provide a postdicted score for how well they thought they performed.

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Participants in the control group were not asked to produce any metacognitive rating.

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Metacognitive Prospective Memory Inventory short version (MPMI-s) - Prospective Memory Ability scale

Rummel, J., Danner, D., & Kuhlmann, B. G. (2019). The short version of the Metacognitive Prospective Memory Inventory (MPMI-s): Factor structure, reliability, validity, and reference data. Measurement Instruments for the Social Sciences, 1(1), 1–8. https://doi.org/10.1186/s42409-019-0008-6

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The task is taken from the WAIS-R (Wechsler, 1981) and is a short working-memory test. Participants saw and immediately recall progressively longer sequences of single-digit numbers presented at a 1-s rate. Two trials for each sequence length were given, starting from a 2-digit sequence, and testing continued until participants missed both trials within the given sequence length.

Wechsler, D. (1981). Wechsler Adult Intelligence Scale, Revised Manual. Psychological Corp.

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Zigmond, A. S., & Snaith, R. P. (1983). The Hospital Anxiety and Depression Scale. Acta Psychiatrica Scandinavica, 67(6), 361–370. https://doi.org/10.1111/j.1600-0447.1983.tb09716.x

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This final questionnaire contains some demographic questions and collects participants’ impressions on the study.

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At the end of the experiment, participants were thanked for their time and debriefed

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This is the sequence of the different tasks and questionnaires. Participants are randomly assigned to one of the experimental conditions.

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