Age-related changes in ongoing thought relate to external context and individual cognition

Understanding how age-related changes in cognition manifest in the real world is an important goal. One means of capturing these changes involves “experience sampling” participant’s self-reported thoughts. Research has shown age-related changes in ongoing thought: e.g., older adults have fewer thoughts unrelated to the here-and-now. However, it is currently unclear how these changes reflect cognitive aging or lifestyle changes. 78 younger adults and 35 older adults rated their thought contents along 20 dimensions and the difficulty of their current activity in their daily lives. They also performed cognitive tasks in the laboratory. In a set of exploratory analyses, we found that older adults spent more time thinking positive, wanted thoughts, particularly in demanding contexts, and less time mind wandering about their future selves. Past-related thought related to episodic memory differently in older and younger adults. These findings inform the use of experience sampling to understand cognitive aging.     

Influencing the occurrence of mind wandering while reading

The current concerns hypothesis suggests that directing attention towards unfulfilled plans of the individual prior to a task would result in more off-task thoughts (or mind wandering). In this experiment, participants were asked to read a scientific text and self-report instances of mind wandering by indicating when they were experiencing task-unrelated thoughts (TUTs) or task-related interferences (TRIs). Prior to reading, participants in the individual plans experimental condition were asked to reflect upon their short-term plans by making a “to do” list while participants in a control condition were asked to make a list of the components of an automobile. In support of the current concerns hypothesis, directing attention towards the short-term plans resulted in significantly more TUTs, but not TRIs. Furthermore, participants in the individual plans condition had significantly lower scores on an assessment of reading comprehension, and this relationship was mediated by the frequency of TUTs.     

Age-related changes in frequency of mind-wandering and task-related interferences during memory encoding and their impact on retrieval

During the performance of cognitive tasks such as memory encoding, attention can become decoupled from the external environment and instead focused on internal thoughts related to the appraisal of the current task (task-related interferences; TRI), or personal thoughts unrelated to the task at hand (mind-wandering; MW). However, the association between the frequency of these thoughts experienced at encoding and retrieval accuracy in young and older adults remains poorly understood. In this study young and older adults encoded lists of words using one of two encoding tasks: judging whether words are man-made/natural (objective task), or whether they are pleasant/neutral (subjective task). We measured the frequency of TRI and MW at encoding, and related them to retrieval accuracy in both age groups. We found that encoding task influenced the type of internal thoughts experienced by young, but not older, adults: young exhibited greater MW in the subjective vs the objective task, and greater TRI in the objective vs subjective encoding task. Second, across both tasks we found marked age-related decreases in both MW and TRI at encoding, and frequency of these thoughts negatively impacted memory retrieval in young adults only. We discuss these findings in relation to current theories of ageing, attention and memory.     

Task-unrelated-thought frequency as a function of age: a laboratory study

Using retrospective reports, Giambra (1977-1978, 1979-1980) found an inverse relation between age and daydreaming/mind wandering. To deal with an alternate explanation of these results based on age-dependent memorial deficiencies and attitudes toward daydreaming/mind wandering and to provide independent convergent validity, five experiments were carried out. Task-unrelated thoughts (TUTs) were taken as the operational definition of daydreams/mind wanderings and their frequency recorded in vigilance tasks. All five experiments found an inverse relation between age (17-92 years, N = 471) and TUTs, confirming the reliability and validity of the earlier studies. The age-dependent reduction in TUTs was considered as evidence of reduced nonconscious information processing with increased age. The results of this study were incompatible with a recent theory that predicts for older individuals an increased input of irrelevant thoughts into working memory due to the older individual's reduced inhibitory control.     

A comparison of visual working memory and episodic memory performance in younger and older adults

Working memory and episodic memory decline with age. However, as they are typically studied separately, it is largely unknown whether age-associated differences are similar. A task design was developed in which visual working memory and episodic memory performances were measured using the same stimuli, with both tasks involving context binding. A 2-back working memory task was followed by a surprise subsequent recognition memory task that assessed incidental encoding of object locations of the 2-back task. The study compared performance of younger (N=30; M_age=23.5, SD_age=2.9, range=20-29) and older adults (N=29; M_age=72.1, SD_age=6.8, range=62-90). Older adults performed worse than younger adults, without an interaction effect. In younger, but not in older adults, performance on the two tasks was related. We conclude that although age differences (Young>Older) are similar in the working memory and incidental associative memory tasks, the relationship between the two memory systems differs as a function of age group.     

Effects of aging on absolute identification of duration

Experiments to examine the effects of aging on the ability to identify temporal durations in an absolute identification task are reported. In Experiment 1, older adults were worse than younger adults in identifying a tone's position within a series of 6 tones of varied durations. In Experiment 2, participants were required to identify a tone's position in 9 tones of varied durations. Older adults' performance was again worse than that of younger adults; moreover, they showed a qualitatively different pattern of errors than younger adults. In Experiment 3, in which the tones varied in pitch, the performance of older adults was worse than that of younger adults, but the error patterns of the 2 groups were similar. The results suggest that older adults have distorted memory representations for durations but not for pitch.     

Motivating meta-awareness of mind wandering: A way to catch the mind in flight?

Given the negative effects of mind wandering on performance, it may be profitable to be aware of task-unrelated thoughts (TUTs) as they occur. The present study investigated whether motivating people to catch TUTs increases meta-awareness. We offered incentives for increased self-catching during reading. To enhance the veracity of these self-reports, we used a “bogus-pipeline” procedure; we convinced participants that their mental states were being covertly monitored using physiological measures. In reality, mind wandering was assessed covertly by a secondary task (“gibberish detection”), and overtly by experience sampling. The results showed that incentives increased the number of self-catches without increasing overall mind wandering. Moreover, both the bogus pipeline and the opportunity for incentives increased the validity of self-reports, evidenced by significantly increased correlations between self-caught and behaviorally assessed mind wandering. We discuss the relevance of this methodological approach for research on mind wandering and research building on introspective reports more generally.     

Effects of age, task, and frequency on variability of finger tapping

The goal was to assess whether prior studies might have overestimated performance variability in older adults in dual task conditions by relying on primary motor tasks that are not constant with aging. 30 younger and 31 older adults performed a bimanual tapping task at four different frequencies in isolation or concurrently with a secondary task. Results showed that performance of younger and older adults was not significantly different in performing the tapping task at all frequencies and with either secondary task, as indicated by mean tapping performance and low number of errors in the secondary tasks. Both groups showed increased variability as tapping frequency increased and with the presence of a secondary task. Tapping concurrently while reading words increased tapping variability more than tapping concurrently while naming colours. Although older participants' performances were overall more variable, no interaction effects with age were found and at the highest frequencies of tapping, younger and older participants did not differ in performance.     

Examining the role of emotional valence of mind wandering: All mind wandering is not equal

To evaluate the role of emotional valence on the impact of mind wandering on working memory (WM) and sustained attention, we reanalyzed data from three independently conducted studies that examined the impact of stress on WM (Banks & Boals, 2016; Banks, Welhaf, & Srour, 2015) and sustained attention (Banks, Tartar, & Welhaf, 2014). Across all studies, participants reported the content of their thoughts at random intervals during the WM or sustained attention task. Thought probes in all studies included a core set of response options for task-unrelated thoughts (TUTs) that were negatively, positively, or neutrally emotionally valenced. In line with theories of emotional valenced stimuli on capture of attention, results suggest negatively valenced TUTs, but not positively valenced TUTs, were related to poorer WM and sustained attention in two studies. Neutral TUTs were related to poorer WM but not sustained attention performance. Implications for models of mind wandering are discussed.     

Age-related differences in idea generation and selection for propositional language

Conceptual preparation mechanisms such as novel idea generation and selection from amongst competing alternatives are critical for language production and may contribute to age-related language deficits. This study investigated whether older adults show diminished idea generation and selection abilities, compared to younger adults. Twenty younger (18–35 years) and 20 older (60–80 years) adults completed two novel experimental tasks, an idea generation task and a selection task. Older participants were slower than younger participants overall on both tasks. Importantly, this difference was more pronounced for task conditions with greater demands on generation and selection. Older adults were also significantly reduced on a semantic, but not phonemic, word fluency task. Overall, the older group showed evidence of age-related decline specific to idea generation and selection ability. This has implications for the message formulation stage of propositional language decline in normal aging.     

Effects of age and type of picture on visuospatial working memory assessed with a computerized jigsaw-puzzle task

We investigated the effect of age and color in a computerized version of the jigsaw-puzzle task. In Experiment 1, young and older adults were presented with puzzles in color and black-and-white line drawings, varying in difficulty from 4 to 9 pieces. Older adults performed the task better with the black-and-white stimuli and younger adults performed better with the color ones. In Experiment 2, new older and young adults identified the same fragmented pictures as fast and accurately as possible. The older group identified the black-and-white stimuli faster than those presented in color, while the younger adults identified both similarly. In Experiment 3A, new older and young groups performed the puzzle task with the same color pictures and their monochrome versions. In Experiment 3B, participants performed a speeded identification task with the two sets. The findings of these experiments showed that older adults have a memory not a perceptual difficulty.     

Exploring the specificity of age-related differences in theory of mind tasks

Tasks assessing theory of mind (ToM) and non-mental state control tasks were administered to young and older adults to examine previous contradictory findings about age differences in mental state decoding. Age differences were found on a verbal ToM task after controlling for vocabulary levels. Older adults achieved significantly lower scores than did younger adults on static and dynamic visual ToM tasks, and a similar pattern was found on non-ToM control tasks. Rather than a specific ToM deficit, older adults exhibited a more general impairment in the ability to decode cues from verbal and visual information about people.     

Attending to music decreases inattentional blindness

This article investigates how auditory attention affects inattentional blindness (IB), a failure of conscious awareness in which an observer does not notice an unexpected event because their attention is engaged elsewhere. Previous research using the attentional blink paradigm has indicated that listening to music can reduce failures of conscious awareness. It was proposed that listening to music would decrease IB by reducing observers’ frequency of task-unrelated thoughts (TUTs). Observers completed an IB task that varied both visual and auditory demands. Listening to music was associated with significantly lower IB, but only when observers actively attended to the music. Follow-up experiments suggest this was due to the distracting qualities of the audio task. The results also suggest a complex relationship between IB and TUTs: during demanding tasks, as predicted, noticers of the unexpected stimulus reported fewer TUTs than non-noticers. During less demanding tasks, however, noticers reported more TUTs than non-noticers.     

Mind wandering while reading easy and difficult texts

Mind wandering is a phenomenon in which attention drifts away from the primary task to task-unrelated thoughts. Previous studies have used self-report methods to measure the frequency of mind wandering and its effects on task performance. Many of these studies have investigated mind wandering in simple perceptual and memory tasks, such as recognition memory, sustained attention, and choice reaction time tasks. Manipulations of task difficulty have revealed that mind wandering occurs more frequently in easy than in difficult conditions, but that it has a greater negative impact on performance in the difficult conditions. The goal of this study was to examine the relation between mind wandering and task difficulty in a high-level cognitive task, namely reading comprehension of standardized texts. We hypothesized that reading comprehension may yield a different relation between mind wandering and task difficulty than has been observed previously. Participants read easy or difficult versions of eight passages and then answered comprehension questions after reading each of the passages. Mind wandering was reported using the probe-caught method from several previous studies. In contrast to the previous results, but consistent with our hypothesis, mind wandering occurred more frequently when participants read difficult rather than easy texts. However, mind wandering had a more negative influence on comprehension for the difficult texts, which is consistent with the previous data. The results are interpreted from the perspectives of the executive-resources and control-failure theories of mind wandering, as well as with regard to situation models of text comprehension.     

Age,working memory,and the Tower of London task

The current study explores the role of three components of working memory in age differences in an executive task, the Tower of London (TOL). The TOL task is sensitive to frontal lobe damage, and is widely used to measure planning ability. Dual tasks were used to test the involvement of the phonological loop (articulatory suppression), visuospatial buffer (pattern tapping), and central executive (random generation) in age effects on the TOL. Older adults showed greater reliance than young on domain-specific verbal and spatial memory components in performing the TOL. In terms of executive function, qualitatively different interference patterns were seen in young and old participants. However, the validity of using random generation tasks to assess executive function in older populations can be questioned. For older participants, performing the TOL loads all components of working memory, whereas for the younger participants the TOL more specifically loads executive functioning.     

Age differences in response selection for pure and mixed stimulus-response mappings and tasks

Two experiments examined effects of mixed stimulus-response mappings and tasks for older and younger adults. In Experiment 1, participants performed two-choice spatial reaction tasks with blocks of pure and mixed compatible and incompatible mappings. In Experiment 2, a compatible or incompatible mapping was mixed with a Simon task for which the mapping of stimulus color to location was relevant and stimulus location was irrelevant. In both experiments, older adults showed larger mixing costs than younger adults and larger compatibility effects, with the differences particularly pronounced in Experiment 1 when location mappings were mixed. In mixed conditions, when stimulus location was relevant, older adults benefited more than younger adults from complete repetition of the task and stimulus from the preceding trial. When stimulus location was irrelevant, the benefit of complete repetition did not differ reliably between age groups. The results suggest that the age-related deficit associated with mixing mappings and tasks is primarily due to older adults having more difficulty separating task sets that activate conflicting response codes.     

Age-related differences in movement strategies and postural control during stooping and crouching tasks

While epidemiologic data suggests that one in four older adults have difficulty performing stooping and crouching (SC) tasks, little is known about how aging affects SC performance. This study investigated differences between young and older adults in lower limb kinematics and underfoot center of pressure (COP) measures when performing a series of SC tasks. Twelve healthy younger and twelve healthy older participants performed object-retrieval tasks varying in: (1) initial lift height, (2) precision demand, and (3) duration. Whole-body center of mass (COM), underfoot COP, and hip and knee angular kinematics (maximum angles and velocities) were analyzed. Compared to younger, older participants moved slower when transitioning into and out of pick-up postures that were characterized by less hip and knee flexion. Older participants also showed a diminished ability to adapt to the changing postural demands of each set of tasks. This was especially evident during longer tasks, whereby older individuals avoided high knee flexion crouching postures that were commonly used by younger participants. Older adults also tended to exhibit faster and more frequent COP trajectory adjustments in the anterior–posterior direction. It is likely that limitations in physical characteristics such as lower limb strength and range of motion contributed to these differences.     

Age-specific differences of dual n-back training

Age-related decline in executive functions can be decisive in performing everyday tasks autonomously. Working memory (WM) is closely related to executive functions, and training of WM has yielded evidence toward cognitive plasticity in older adults. The training effects often transfer to untrained tasks and functions. These effects have mostly been shown in processes such as WM and attention, whereas studies investigating transfer to executive functions have been scarce. We trained older adults aged 57–73 years in a WM training task that was reported to be effective in producing transfer in young adults. The training intervention consisted of a dual n-back task including independently processed auditory and visual n-back tasks. We investigated transfer to tasks engaging executive functions, and compared the effects in older adults to those reported in young adults. We found that both training groups improved in the training task. Although the training effect in older adults was smaller than the training effect in young adults, the older adults still showed a notable improvement so that after training they performed on the same level as young adults without training. The older adults also showed transfer to an untrained WM updating task, a result that was in accordance with the findings in young adults; other transfer effects in older adults were lacking. We conclude that although transfer effects were scarce, the present study provides encouraging evidence toward the possibilities to compensate for age-related decline in executive functions by a WM training intervention.     

Future time perspective drives younger and older adults to continue investing in failing activities

Inspired by socioemotional selectivity theory, we investigated age differences in further investment in failing situations by considering goal type and future time perspective. In Experiment 1, 32 younger and 30 older adults reported their likelihood of continued investing following an unsuccessful investment. Older adults were more willing to invest with emotional goals as opposed to knowledge and unspecified goals, while younger adults showed a greater willingness to invest with emotional and knowledge goals rather than unspecified goals. In Experiment 2, another sample of 32 younger and 34 older adults completed the same decision tasks as those in Experiment 1. After future time perspective restriction, the younger adults made decisions resembling Experiment 1's older adults, while after future time perspective expansion, the older adults behaved like Experiment 1's younger adults. These results indicate that future time perspective modification could reverse participants' goal prioritisation, manifesting in differential willingness to pursue further investment in decision scenarios with different goals. Our results represent important steps towards understanding the mechanism of older and younger adults' further investment in failing situations and illustrate that forging connections between the lifespan theory of motivation and further investment decision is critical for understanding adults' decision behaviours.     

When and how did you go wrong? Characterizing mild functional difficulties in older adults during an everyday task

ABSTRACT

Mild functional difficulties associated with cognitive aging may be reliably measured by coding “micro-errors” during everyday tasks, like meal preparation. Micro-errors made by 25 older adult and 48 younger adults were coded on four dimensions to evaluate the influence of: 1) poor error monitoring; 2) goal decay; 3) competition for response selection when switching to a new subtask; and 4) interference from distractor objects. Micro-errors made by young adults under a dual task load also were analyzed to determine the influence of overall performance level. Older adults’ micro-errors were observed when switching to a new subtask and to unrelated distractors. Slowed error monitoring and goal decay also influenced micro-errors in older adults, but not significantly more so than younger adults under the dual task. Interventions to reduce interference from distractors and to increase attention at critical choice points during tasks may optimize everyday functioning and preclude decline in older adults.