An Examination of Associative Memory using Functional Near Infrared Spectroscopy
Moss, Charlotte · Deep Blue (University of Michigan) · 2023
Functional Near-Infrared Spectroscopy (fNIRS) is a neuroimaging technology that overcomes many of functional MRI’s technical limitations (including lower cost, motion tolerance, and higher temporal resolution). While some tasks have been validated in fNIRS, many areas of study, such as associative memory, have not been thoroughly examined. Functional MRI studies have shown that associative memory engages multiple brain regions, including the ventral and dorsal visual streams, medial temporal lobe, and frontal cortical areas. However, few studies have examined whether similar patterns of cortical activation are detected in older adults using fNIRS. To investigate this issue, we recorded fNIRS from 30 cognitively intact older adults encoding object-location associations of common household objects within a virtual room. Results showed greater activation for novel compared to repeated object-location pairs in the occipital and posterior parietal cortices, as well as regions in dorsolateral and ventrolateral frontal cortices. Our overall results are consistent with prior fMRI evidence from associative memory studies, while also suggesting some differences between fNIRS and fMRI methodologies. A key future direction includes comparing fNIRS and fMRI results within the same participants to further understand the differences between the two neuroimaging techniques.