Is subjective age a multidimensional construct in a Japanese sample aged 20-89?

AIM: Subjective age is an emerging concept in the aging literature that predicts various aspects of quality of life, but its nature is not fully understood. This study aimed to explore whether subjective age is a unidimensional or a multidimensional construct and its relationship with quality of life through a multi-aspects approach. METHODS: We examined subjective age for 2896 Japanese adults aged 20-89 by using five subjective age measures and questions with regard to their quality of life and analyzed the results with four indexes. RESULTS: Factor analyses found one factor for the measures, indicating a unidimensional construct. Yet, the multi-aspect analyses revealed unique features of the measures, especially in relation to variables on the quality of life. Among the five measures, Perceived physical age is the best predictor of life satisfaction and perception of cognitive function (i.e., memory), such that the more satisfied individuals are with their life, the younger they feel. Ideal age is another best predictor in the opposite direction, such that the less satisfied individuals are with their life, the younger they want to be. CONCLUSION: Although the factor analyses revealed subjective age to be a unidimensional construct, the present results also suggest the possibility that it is multidimensional in nature. In future studies, a more systematic approach is essential for a thorough exploration of scales designed to measure the multiple aspects of subjective age. This is particularly crucial in the context of predicting our well-being. Such scales could also enable us to compare the universality and individuality of subjective age across different cultures. Geriatr Gerontol Int 2024; 24: 253-258.

Do eye movements enhance visual memory retrieval?

When remembering an object at a given location, participants tend to return their gaze to that location even after the object has disappeared, known as Looking-at-Nothing (LAN). However, it is unclear whether LAN is associated with better memory performance. Previous studies reporting beneficial effects of LAN have often not systematically manipulated or assessed eye movements. We asked 20 participants to remember the location and identity of eight objects arranged in a circle, shown for 5 s. Participants were prompted to judge whether a location statement (e.g., "Star Right") was correct or incorrect, or referred to a previously unseen object. During memory retrieval, participants either fixated in the screen center or were free to move their eyes. Results reveal no difference in memory accuracy and response time between free-viewing and fixation while a LAN effect was found for saccades during free viewing, but not for microsaccades during fixation. Memory performance was better in those free-viewing trials in which participants made a saccade to the critical location, and scaled with saccade accuracy. These results indicate that saccade kinematics might be related to both memory performance and memory retrieval processes, but the strength of their link would differ between individuals and task demands.

Gaze Bias in Preference Judgments by Younger and Older Adults.

Individuals' gaze behavior reflects the choice they will ultimately make. For example, people confronting a choice among multiple stimuli tend to look longer at stimuli that are subsequently chosen than at other stimuli. This tendency, called the gaze bias effect, is a key aspect of visual decision-making. Nevertheless, no study has examined the generality of the gaze bias effect in older adults. Here, we used a two-alternative forced-choice task (2AFC) to compare the gaze behavior reflective of different stages of decision processes demonstrated by younger and older adults. Participants who had viewed two faces were instructed to choose the one that they liked/disliked or the one that they judged to be more/less similar to their own face. Their eye movements were tracked while they chose. The results show that the gaze bias effect occurred during the remaining time in both age groups irrespective of the decision type. However, no gaze bias effect was observed for the preference judgment during the first dwell time. Our study demonstrated that the gaze bias during the remaining time occurred regardless of decision-making task and age. Further study using diverse participants, such as clinic patients or infants, may help to generalize the gaze bias effect and to elucidate the mechanisms underlying the gaze bias.

How Japanese adults perceive memory change with age: middle-aged adults with memory performance as high as young adults evaluate their memory abilities as low as older adults.

The characteristics of self-referent beliefs about memory change with age. The relationship between beliefs and memory performance of three age groups of Japanese adults was investigated. The beliefs measured by the Personal Beliefs about Memory Instrument (Lineweaver & Hertzog, 1998) differed among the age groups and between sexes. In most scales, the ratings by middle-aged adults were as low as those by older adults, which were lower than those by young adults. Women perceived their memory abilities as lower than men's, with no interaction between age and sex, suggesting the difference remains across the lifespan. For middle-aged adults, the better they performed in cued-recall, free recall, and recognition, the lower they evaluated their memory self-efficacy, while few relationships were found for other groups. Our results suggest that cognitive beliefs change with age and that investigating the beliefs of the middle-aged adults is indispensable to elucidate the transition of beliefs.

[Japanese adults' general beliefs about changes in the ability to remember from childhood to old age as measured by the General Beliefs about Memory Instrument (GBMI)].

This study examined and compared beliefs about the ability to remember of three groups of adults: 99 young, 97 middle-aged, and 104 older adults. The beliefs were assessed by asking participants to indicate the expected trajectory over the lifespan on a graphic rating scale, the General Beliefs about Memory Instrument (GBMI) (Lineweaver & Hertzog, 1998). The results showed the following. Although all age groups expect a decline in the ability to remember with age with the peak around 20-30 years old, older adults perceive an age-related sharp decline later in life than the other age groups do. All age groups perceive that remembering names is more affected by age than any other memory abilities. The trajectory of age decline in remembering in general coincides with that in remembering trivia. All age groups believe that the ability to remember at the age of 10 is as good as at the age of 40. All age groups responded to the scales based mainly on the abilities based on their experiences.

Effects of aging and divided attention on recognition memory processes for single and associative information.

In the divided attention paradigm to test age-related associative memory deficits, whether the effects of divided attention occur at encoding or retrieval has not been clarified, and the effect on retention has not been studied. This study explored whether and how much divided attention at either encoding, retention, or retrieval diminished accuracy in recognizing a single feature (object or location) and associated features (object+location) by 23 elderly people (13 women; M age = 70.6 yr., SD = 2.8) recruited from a neighborhood community circle, and 29 female college students (M age = 20.8 yr., SD = 1.1). The results showed a significant decline in memory performance for both age groups due to divided attention in location and associative memory at retention, suggesting that the retention process demands attentional resources. Overall, regardless of their relative deficiency in associative memory, older adults showed an effect of divided attention comparable to that of younger adults in a recognition task.

Effects of self-paced encoding and practice on age-related deficits in binding three features.

Although much literature suggests that the age-related decline in episodic memory could be due to difficulties in binding features of information, previous studies focused mainly on memory of paired associations rather than memory of multiple bound features. In reality, however, there are many situations that require binding multiple features together simultaneously. Thus, this three-part experimental study using a working memory task examined two fundamental questions: whether and how well older adults perform a working memory task that requires them to bind three features together (Experiment 1), and whether and how much older adults' memory of units of three bound features could be improved by self-paced encoding and 3 weeks practice (Experiments 2 & 3). The results indicated that although older adults performed as well as young adults in remembering one unit of three features, they showed a deficit in remembering two units, making more severe errors than young adults, and the difference between the two age groups increased when remembering three units. However, older adults improved their memory performance substantially by two means: self-paced encoding and practice. The former primarily shortened reaction times while the latter primarily improved memory accuracy. With self-paced encoding, older adults were also capable of binding at least three units during encoding. Thus, it is possible to assume that under an optimal encoding period, the age-related deficits occur probably not at encoding but at retention and/or retrieval.

Improving sensitivity of the recognition task in the Alzheimer's Disease Assessment Scale.

This paper presents an alternative measure for scoring the recognition memory task in the Alzheimer's Disease Assessment Scale (ADAS), which is one of the most common screening tests. Memory studies routinely take into account not only correct responses to old items (Hits) but also incorrect responses to new items (False Alarms). Here, a bias-corrected measure of recognition memory, Hits minus False Alarms (called Pr), is computed and its significance evaluated against the original measure, Hits. 28 male and 40 female healthy elderly people (M age= 68.5 yr., SD=3.5) recruited from the neighborhood community participated in this study. Multiple stepwise regression analyses first with Hit Rate then False Alarm Rate showed that False Alarm Rate significantly improved R(2) in the two subscale scores of the Wechsler Memory Scale-Revised and scores of the Mini-Mental State Exam. Thus, this new measure taking into account false responses may be more sensitive and useful to detect early stages of cognitive dysfunction.