Investigation of the relationship between tissue characteristics and time perception in healthy aging

Aktaş Dinçer, Hayriye
Brain ubiquitously receives temporal information. As people get older, their timing performances change. Interval timing requires cognitive resources such as attention, long-term memory, and working memory. Unfortunately, these functions deteriorate with aging. Changes in time perception are reported in healthy aging, as are several different neuropsychiatric disorders. Although age-related changes in time perception have been amply described in the literature, the actual underlying mechanisms remain controversial. This study included a total of 33 young (mean age = 23.31 years) and 33 old (mean age = 67.63 years) individuals who performed a time bisection task with a range of 1.25-2.5 seconds. The young and old participants showed similar time bisection performances (p ≥ 0.05). The experimental design was strictly controlled to minimize the effects of age-related declines in cognitive functions. Contrary to psychometric measurements, self-rated reports indicated that the impressions of the participants about present time perception differ though aging. The spin lattice relaxation times (T1) on entire brain were mapped with an ROI based method. T1 prolongation with aging was demonstrated on numerous cortical and subcortical area, which was interpreted as increased demyelination in these structures. vi Also, the relationship between MRI and behavioral data was investigated: significant correlations between behavioral outcomes and various brain structures including timing circuits such as cerebellum and hippocampus were shown. Finally, regression analyses showed that one of the basic measures of time perception, bisection point, is predicted by the T1 values of certain subcortical brain areas such as cerebellum, hippocampus and putamen.
Citation Formats
H. Aktaş Dinçer, “Investigation of the relationship between tissue characteristics and time perception in healthy aging,” Thesis (Ph.D.) -- Graduate School of Natural and Applied Sciences. Biomedical Engineering., Middle East Technical University, 2019.