TY - JOUR

T1 - Flexible allocation of attention in time or space across the life span

T2 - Theta and alpha oscillatory signatures of age-related decline and compensation as revealed by MEG

AU - Callaghan, Eleanor

AU - Holland, Carol A

AU - Kessler, Klaus

PY - 2018/11/3

Y1 - 2018/11/3

N2 - In our recent behavioural research (Callaghan et al., 2017) we reported age-related changes in the speed of switching between temporal and spatial attention. Using magnetoencephalography (MEG), we now compared the neural signatures between three age groups (19-30, 40-49 and 60+ years) and found differences in task-related modulation and cortical localisation of alpha and theta oscillations as well as in functional network connectivity. Efficient (fast) switching between the temporal and spatial attention tasks in the youngest group was reflected by parietal theta effects that were absent in the older groups. Difficulties in refocusing attention in the older and middle-aged adults (slowed response times) were accompanied by reduced theta power modulation in occipital and cerebellar regions. Older and middle-aged adults seem to compensate for this posterior theta deficit with increased recruitment of frontal (both groups) and temporal (older group) areas, possibly reflecting a greater dependence on top-down attentional control. Importantly, rather than theta oscillatory connectivity becoming weaker with age due to increased neural noise, both older age groups displayed stronger and more widely distributed connectivity. However, differences in alpha-band modulations did not translate into enhanced connectivity patterns in the older groups. Overall we conclude that theta oscillations and connectivity reflect compensatory strategies in older and middle age that induce a posterior to anterior processing shift, while alpha oscillations might reflect increased neural noise but require further investigation.

AB - In our recent behavioural research (Callaghan et al., 2017) we reported age-related changes in the speed of switching between temporal and spatial attention. Using magnetoencephalography (MEG), we now compared the neural signatures between three age groups (19-30, 40-49 and 60+ years) and found differences in task-related modulation and cortical localisation of alpha and theta oscillations as well as in functional network connectivity. Efficient (fast) switching between the temporal and spatial attention tasks in the youngest group was reflected by parietal theta effects that were absent in the older groups. Difficulties in refocusing attention in the older and middle-aged adults (slowed response times) were accompanied by reduced theta power modulation in occipital and cerebellar regions. Older and middle-aged adults seem to compensate for this posterior theta deficit with increased recruitment of frontal (both groups) and temporal (older group) areas, possibly reflecting a greater dependence on top-down attentional control. Importantly, rather than theta oscillatory connectivity becoming weaker with age due to increased neural noise, both older age groups displayed stronger and more widely distributed connectivity. However, differences in alpha-band modulations did not translate into enhanced connectivity patterns in the older groups. Overall we conclude that theta oscillations and connectivity reflect compensatory strategies in older and middle age that induce a posterior to anterior processing shift, while alpha oscillations might reflect increased neural noise but require further investigation.

U2 - 10.1101/461020

DO - 10.1101/461020

M3 - Journal article

JO - Biorxiv

JF - Biorxiv

ER -