Age-related deterioration of performance and increase of cortex activity comparing time- versus item-controlled fNIRS measurement

Abstract

In our aging society, research into neurodegenerative processes is of great interest. Thereby, cortical activation under different neurocognitive conditions is considered to be a promising predictor. Against this background, the executive functions of a total of 250 healthy older adults (53–84 years) have been investigated using the Trail Making Test (TMT) and functional near-infrared spectroscopy in a block design. We investigated effects of age on the performance and cortical blood oxygenation during the TMT. Since it is assumed that older people may compensate for cognitive deficits by slowing their processing speed, we additionally analyzed the cortical blood oxygenation per solved item. Our results showed a significant decrease in processing speed in older participants compared to middle-aged individuals, however, also lower error rates during TMT part A. On a neurophysiological level, we observed increased cortical blood oxygenation in the older participants when completing the TMT. Finally, with respect to the combined measurement (O2Hb/item), no significantly higher hemodynamic cortical response per item was found within the older participants. The results confirm a deterioration of cognitive performance and an increase of cortical activity with increasing age. The findings are discussed in the light of current research.

Effects of aging on functional connectivity in a neurodegenerative risk cohort: resting state versus task measurement using near-infrared spectroscopy

“…Notably, only the FC between the left IFG and right SAC was positively correlated with age in our investigation. A generally increased cortical activity measured via fNIRS in older participants during performance of the TMT has already been described by us as well as discussed within the context of a possible compensation mechanism 86 . For instance, Respino et al 25 reported a positive correlation between an elevated regional homogeneity within the dACC as part of the CCN and executive performance in the context of late-life depression and suggested this to be a possible compensation mechanism, too.…”

Distinct age-related brain activity patterns in the prefrontal cortex when increasing cognitive load: A functional near-infrared spectroscopy study

“…These effects have been observed across age-groups with older adults over-recruiting as compensation at lower cognitive loads, then reaching neural resource limits at higher loads, leading to poorer performance (compensation related utilization of neural circuits hypothesis or CRUNCH, [ 21 , 23 ]). However, Van Ruitenbeek et al [ 31 ] recently failed to observe brain activity attenuation in older adults at high cognitive load task levels and instead, found more brain activation using fMRI [ 32 ], similar to Blum et al [ 33 ], who also observed task-load increases in brain activity in older adults using functional near-infrared spectroscopy (fNIRS), suggesting that older adults may be able to deploy additional neural resources at high cognitive loads. Such inconsistencies make it difficult to characterize healthy aging brain activity patterns, and particularly, the role of compensation, highlighting the need for more research.…”

“…fNIRS is based on haemodynamic changes due to metabolic demand as a proxy for neural activity and uses light emitting optodes at near-infrared wavelengths to determine changes in oxy and deoxyhemoglobin in cortical areas [34,35]. Past research has shown that fNIRS is sensitive to age-related differences in brain activity [33,36,37] and to distinct cognitive loads [38][39][40][41][42]. In addition, due to fNIRS being an emerging technique, there have been recent improvements from traditional analyses that show better control over type I errors [43,44], making it an increasingly robust neuroimaging method [42].…”

Astaxanthin: The possible effects of this carotenoid on disease, inflammation and aging control. A meta-analysis

“…As the brain is the organ most susceptible to aging, it can provide a sensitive environment for the development of neurodegenerative diseases such as Parkinson's disease and Alzheimer's disease [28] . Therefore, exploring methods to slow or reverse brain aging with nutraceuticals such as ATX may be a promising avenue for the near future, as this carotenoid exhibits potent antioxidant, anti-inflammatory and neuroprotective effects.…”