Age-related changes in the relationship between visual exploration and hippocampal activity

NEUROPSYCHOLOGIA

卷:119

Article

Liu, Zhong-Xu¹  Shen, Kelly¹  Olsen, Rosanna K.^1,2  Ryan, Jennifer D.^1,2,3 

[1] Baycrest, Rotman Res Inst, 3560 Bathurst St, Toronto, ON M6A 2E1, Canada

[2] Univ Toronto, Dept Psychol, Toronto, ON M5S 3G3, Canada

[3] Univ Toronto, Dept Psychiat, Toronto, ON, Canada

关键词: fMRI;    Visual exploration;    Eyetracking;    Memory;    Face processing;    Hippocampus;    Neuroimaging;   

DOI  :  10.1016/j.neuropsychologia.2018.07.032

来源: Elsevier

【 摘 要 】

Deciphering the mechanisms underlying age-related memory declines remains an important goal in cognitive neuroscience. Recently, we observed that visual sampling behavior predicted activity within the hippocampus, a region critical for memory. In younger adults, increases in the number of gaze fixations were associated with increases in hippocampal activity (Liu et al., 2017). This finding suggests a close coupling between the oculomotor and memory system. However, the extent to which this coupling is altered with aging has not been investigated. In this study, we gave older adults the same face processing task used in Liu et al. (2017) and compared their visual exploration behavior and neural activation in the hippocampus and the fusiform face area (FFA) to those of younger adults. Compared to younger adults, older adults showed an increase in visual exploration as indexed by the number of gaze fixations. However, the relationship between visual exploration and neural responses in the hippocampus and FFA was weaker than that of younger adults. Older adults also showed weaker responses to novel faces and a smaller repetition suppression effect in the hippocampus and FFA compared to younger adults. All together, this study provides novel evidence that the capacity to bind visually sampled information, in real-time, into coherent representations along the ventral visual stream and the medial temporal lobe declines with aging.

【 授权许可】

Free