Aging effects on neural processing of rhythm and meter

When listening to musical rhythm, humans can perceive and move to beat-like metrical pulses. Recently, it has been hypothesized that meter perception is related to brain activity responding to the acoustic fluctuation of the rhythmic input, with selective enhancement of the brain response elicited at meter-related frequencies. In the current study, the electroencephalography (EEG) was recorded while younger (<35) and older (>60) adults listened to rhythmic patterns presented at two different tempi while intermittently performing a tapping task. Despite significant hearing loss compared to younger adults, older adults showed preserved brain activity to the rhythms. However, age effects were observed in the distribution of amplitude across frequencies. Specifically, in contrast with younger adults, older adults showed relatively larger amplitude at the frequency corresponding to the rate of individual events making up the rhythms as compared to lower meter-related frequencies. This difference is compatible with larger N1-P2 potentials as generally observed in older adults in response to acoustic onsets, irrespective of meter perception. These larger low-level responses to sounds have been linked to processes by which age-related hearing loss would be compensated by cortical sensory mechanisms. Importantly, this low-level effect would be associated here with relatively reduced neural activity at lower frequencies corresponding to higher-level metrical grouping of the acoustic events, as compared to younger adults.

How Cues of Being Watched Promote Risk Seeking in Fund Investment in Older Adults

Social cues, such as being watched, can subtly alter fund investment choices. This study aimed to investigate how cues of being watched influence decision-making, attention allocation, and risk tendencies. Using decision scenarios adopted from the “Asian Disease Problem,” we examined participants’ risk tendency in a financial scenario when they were watched. A total of 63 older and 66 younger adults participated. Eye tracking was used to reveal the decision-maker’s attention allocation (fixations and dwell time per word). The results found that both younger and older adults tend to seek risk in the loss frame than in the gain frame (i.e., framing effect). Watching eyes tended to escalate reckless gambling behaviors among older adults, which led them to maintain their share in the depressed fund market, regardless of whether the options were gain or loss framed. The eye-tracking results revealed that older adults gave less attention to the sure option in the eye condition (i.e., fewer fixations and shorter dwell time). However, their attention was maintained on the gamble options. In comparison, images of “watching eyes” did not influence the risk seeking of younger adults but decreased their framing effect. Being watched can affect financial risk preference in decision-making. The exploration of the contextual sensitivity of being watched provides us with insight into developing decision aids to promote rational financial decision-making, such as human-robot interactions. Future research on age differences still requires further replication.

Pronoun production remains stable over the adult lifespan for contexts with topic continuity

A prevalent finding in the referential communication literature is that older adults produce more ambiguous pronouns than younger adults, likely because they have difficulty determining the prominence of referents. This finding has been widely understood to reflect a general age-related deficit in communication. However, all studies from this line of work have used materials involving topic shifts (i.e. when the to-be-named referent shifts from one character to another, which requires perspective-taking and can be cognitively costly). To determine the extent to which younger and older adults’ pronominal use diverges, we investigated whether other aspects of the discourse context influence age-related differences in referential choice, apart from topic shifts. Here we tested a large sample of adults (N=496, ages 18-82) using narrative elicitation tasks across four experiments and nine contexts of topic continuity (i.e. contexts in which the to-be-named referent remained the same). In Experiments 1 and 2, we varied the number of characters in the scene while keeping the sex/gender of the characters distinct and found that pronominal use did not differ by age for scenes with 1, 2, and 3 characters. In Experiments 3 and 4, we varied the number of characters, the sex/gender of those characters (such that they were the same or different), and the linguistic emphasis placed on the main character. Again, we found no age differences across all conditions. Taken together, our findings suggest that older adults’ difficulty with prominence estimates is not all- encompassing, but rather appears to be confined to contexts involving topic shifts.

Validation of the Geriatric Anxiety Inventory in younger adults

This study investigated the psychometric properties of the Geriatric Anxiety Inventory (GAI) in younger adults. Participants were 212 younger adults age M = 22 (range = 17–53) years. They completed a demographic information questionnaire and self-report measures: the GAI, the Depression Anxiety Stress Scales (DASS), the Generalized Anxiety Disorder–7 (GAD-7), the Patient Health Questionnaire–9 (PHQ-9), the Penn State Worry Questionnaire (PSWQ), and the Worry Behaviors Inventory (WBI). Data from the GAI were collected at two time points, one week apart, and data from other self-report measures were collected once via Qualtrics, an online survey platform. The internal consistency and test–retest score reliability of the GAI were excellent. It had good congruent validity with other anxiety measures, limited divergent validity with depression measures, and sound convergent validity with worry measures. The GAI showed good discrimination between probable cases and noncases of generalized anxiety disorder (participants who scored ⩾8 on the GAD-7) and its optimal cutoff score for probable cases of GAD was ⩾12. A unidimensional component structure of the GAI best fit this study’s data. This study has provided preliminary evidence that the GAI is reliable and valid for use in an Australian sample of younger adults.

Training History-Dependent Functional Role of EMG Model-Predicted Antagonist Moments in Knee Extensor Moment Generation in Healthy Young Adults

Resistance training (RT) improves the skeletal muscle’s ability to generate maximal voluntary force and is accompanied by changes in the activation of the antagonist muscle which is not targeted primarily by RT. However, the nature and role of neural adaptation to RT in the antagonist muscle is paradoxical and not well understood. We compared moments, agonist muscle activation, antagonist activation, agonist-antagonist coactivation, and electromyographic (EMG) model-predicted moments generated by antagonist hamstring muscle coactivation during isokinetic knee extension in leg strength-trained (n = 10) and untrained (n = 11) healthy, younger adults. Trained vs. untrained adults were up to 58% stronger. During knee extension, hamstring activation was 1.6-fold greater in trained vs. untrained adults (p = 0.022). This hamstring activation produced 2.6-fold greater model-predicted antagonist moments during knee extension in the trained (42.7 ± 19.55 Nm) vs. untrained group (16.4 ± 12.18 Nm; p = 0.004), which counteracted (reduced) quadriceps knee extensor moments ~43 Nm (0.54 Nm·kg−1) and by ~16 Nm (0.25 Nm·kg−1) in trained vs. untrained. Antagonist hamstring coactivation correlated with decreases and increases, respectively, in quadriceps moments in trained and untrained. The EMG model-predicted antagonist moments revealed training history-dependent functional roles in knee extensor moment generation.

Pneumomediastinum: retrospective analysis of 19 cases and an innovation proposal in classification

Background Guidelines to standardize treatment and follow-up strategies in pneumomediastinum cases are lacking. The aim of the study was to evaluate the etiology in pneumomediastinum cases and the results of treatment and follow-up. Results Nineteen patients with pneumomediastinum who were followed up in our clinic between 2015 and 2020 comprised the study population. Among the patients, 16 (84.2%) were male, and the mean age was 31.15 years. The chief presenting complaints were chest pain and dyspnea. Pneumomediastinum was spontaneous in 15/19 patients (including spontaneous pneumomediastinum with an underlying pathology in 3/15), traumatic in 3/19, and iatrogenic in 1/19. Spontaneous pneumomediastinum without underlying pathology was seen in younger adults (mean age: 23 years). Surgical intervention in traumatic and iatrogenic pneumomediastinum cases was compared with spontaneous cases and no statistically significant difference was observed (p=0.178). The mean hospital stay of all patients was 3.15 days. Only one patient had a recurrence and died, which was later determined to be a secondary spontaneous pneumomediastinum case. Conclusion Pneumomediastinum often occurs with an underlying pathology in advancing age and as spontaneous in younger patients. Therefore, “secondary spontaneous pneumomediastinum” subclass should be evaluated in the classification to facilitate to create a standard guideline and prevent overdiagnosis and overtreatment.

Age Differences in the Social Associative Learning of Trust Information

Trust is a key component of social interaction. Older adults, however, often exhibit excessive trust relative to younger adults. One explanation is that older adults may learn to trust differently than younger adults. Here, we examine how younger (N=33) and older adults (N=30) learn to trust over time. Participants completed a classic iterative trust game with three partners. Younger and older adults shared similar amounts but differed in how they shared money. Compared to younger adults, older adults invested more with untrustworthy partners and less with trustworthy partners. As a group, older adults displayed less learning than younger adults. However, computational modeling shows that this is because older adults are more likely to forget what they have learned over time. Model-based fMRI analyses revealed several age-related differences in neural processing. Younger adults showed prediction error signals in social processing areas while older adults showed over-recruitment of several cortical areas. Collectively, these findings suggest that older adults attend to and learn from social cues differently from younger adults.

Patterns of handgun divestment among handgun owners in California

Background Little is known about voluntary divestment of firearms among US firearm owners. Here, we aim to estimate the proportion of handgun owners who divest their handguns in the years following their initial acquisition; examine the timing, duration, and dynamics of those divestments; and describe characteristics of those who divest. Methods We use data from the Longitudinal Study of Handgun Ownership and Transfer, a cohort of registered voters in California with detailed information on 626,756 adults who became handgun owners during the 12-year study period, 2004–2016. For the current study, persons were followed from the time of their initial handgun acquisition until divestment, loss to follow-up, death, or the end of the study period. We describe the cumulative proportion who divest overall and by personal and area-level characteristics. We also estimate the proportion who reacquired handguns among persons who divested. Results Overall, 4.5% (95% CI 4.5–4.6) of handgun owners divested within 5 years of their first acquisition, with divestment relatively more common among women and among younger adults. Among those who divested, 36.6% (95% CI 35.8–37.5) reacquired a handgun within 5 years. Conclusions Handgun divestment is rare, with the vast majority of new handgun owners retaining them for years.