Research Spotlights: January 2024

The roles of aging and reward sensitivity on auditory and reward networks

In this study funded by NIA, researchers explored functional brain connectivity within and across auditory and reward networks and measured cross-sectional differences in those connectivity patterns between younger adults (YA; N=24; ages 18-23) and older adults (OA; N=24; ages 54-89). The study design included resting state fMRI and tasked-based fMRI, which consisted of listening to 24 different snippets of music and rating familiarity and liking for each. Musical stimuli included a wide range of musical genres, and a subset of the stimuli were participant selected. The investigators hypothesized that music would increase functional connectivity above rest, that well-liked music would evoke greater activity in auditory and reward networks for both groups, and that connectivity patterns would differ between YAs and OAs.

For both participant groups, all music that triggered a rating, whether positive, neutral, or negative, activated auditory regions of the brain. Activity and connectivity in both auditory and reward networks increased linearly with liking ratings. OAs had lower levels of within-network connectivity with a more globally diffuse co-activation across brain regions. The authors note that music-based interventions “may benefit from this finding by emphasizing strategies that are known to pull in out-of-network processes” in OAs.

Significantly higher connectivity between the reward network and bilateral auditory cortex was observed across all participants when they engaged in self-selected music, as compared to researcher-selected music. That is, having agency in music selection enhanced effects. Agency has previously been shown to affect health outcomes of music-based interventions. However, this is the first report that identifies how specific changes in network connectivity relate to agency in music listening and suggests neural targets for music-based intervention development.

Limitations of this study include differences in the age spans and proportion of men and women between the groups.

Citation:
Belden A, Quinci MA, Geddes M, Donovan NJ, Hanser SB, Loui P. Functional Organization of Auditory and Reward Systems in Aging. J Cogn Neurosci. 2023 Oct 1;35(10):1570-1592. doi: 10.1162/jocn_a_02028. PMID: 37432735; PMCID: PMC10513766.

ABCD joins the band: the shared musical environment during childhood, language, and executive function

As part of the Adolescent Brain Cognitive Development (ABCD) initiative supported by NIDA, NIDCD, NIAAA, and NIA, Gustavson et al. examined the relationships between musical experiences, language, and cognition, as well as the genetic and environmental influences on childhood music experiences. These secondary analyses used baseline data from participants at 9-10 years of age, which include measures of exposure to musical instruments (including voice). The investigators also examined the frequency of active engagement with musical instruments and passive listening to music. Behavioral analyses used data from the full ABCD cohort (N = 11,876); analyses differentiating additive genetic influences from shared and non-shared environmental influences were based on the twin sub-sample (N = 1543).

The most striking finding from this study was that musical instrument exposure was significantly positively associated with language ability, an executive function composite, and working memory specifically. Passive music listening also appeared to be significantly correlated with working memory performance. There were no other associations seen with frequency of engagement with music, either actively or passively. Moreover, although visual art and soccer exposure also demonstrated positive associations with cognitive functions, the correlations were stronger for music. The primary driver of the associations between musical instrument exposure, language, and executive function appears to be shared environment, even when controlling for parental income and education. The authors hypothesize that a key environmental factor might be the presence (or absence) of music programs in schools.

Citation:
Gustavson DE, Nayak S, Coleman PL, Iversen JR, Lense MD, Gordon RL, Maes HH. Heritability of Childhood Music Engagement and Associations with Language and Executive Function: Insights from the Adolescent Brain Cognitive Development (ABCD) Study. Behav Genet. 2023 May;53(3):189-207. doi: 10.1007/s10519-023-10135-0. Epub 2023 Feb 9. PMID: 36757558; PMCID: PMC10159991.

How infant-directed song captures attention

Infant-directed (ID) speech and song have long been associated directly with language development in infancy and early childhood, but the factors that contribute to these effects have not been fully explored. In this study, researchers supported by NIDCD, NICHD, and NIMH investigated the impact of ID song on infant attention to caregiver mouths across 6 time points in a longitudinal sample of typically developing 3–12-month-olds (N=299; 155 male, 144 female). Eye-tracking data were collected during exposure to audiovisual clips of female actors producing ID song and speech. Common, playful song clips were used. The audiovisual stimuli were designed to reflect natural variability and thereby maximize ecological validity.

Although infants preferentially looked at the actors’ eyes until 12 months of age, infant mouth-looking increased significantly during the first year of life, for both speech and song. Increases in relative mouth-looking started earlier and increased faster with ID song clips as compared to ID speech. Significantly increased mouth-looking was seen by 6.4 months of age for song. Additional analyses revealed that audiovisual aspects specific to ID song--such as slower tempo, increased rhythmicity, heightened positive affect, and increased audiovisual synchrony--all contributed to increased infant attention to mouths. Further longitudinal studies of this kind could reveal specific audiovisual features and precise developmental sensitive periods during which interventions using ID song could support language acquisition.

Citation:
Alviar C, Sahoo M, Edwards LA, Jones W, Klin A, Lense M. Infant-directed song potentiates infants' selective attention to adults' mouths over the first year of life. Dev Sci. 2023 Sep;26(5): e13359. doi: 10.1111/desc.13359. Epub 2023 Jan 11. PMID: 36527322; PMCID: PMC10276172.