Age-related differences in viewer-rotation tasks: is mental manipulation the key factor?

Using a viewer-centered frame of reference (VCFR) paradigm, we examined whether the necessity to mentally manipulate the frame of reference can explain why older adults were found to be impaired on a variety of spatial memory tasks. Twenty-four younger participants (18-35 years of age) and 24 older participants (65-78 years of age) performed a pointing task under four conditions in which a physical or imagined rotation was induced. In three conditions (updating, imagining, and ignoring), the frame of reference was shifted after encoding, which required a mental manipulation at the time of retrieval. In a control condition, the VCFR was held constant. Overall results show that the necessity to mentally manipulate the VCFR accentuates age-related differences. The presence of mental manipulation should therefore be considered when one is interpreting age-related differences found in spatial memory tasks.