The intention to execute a movement can modulate our perception of sensory events; however, theoretical accounts of these effects, and also empirical data, are often contradictory. We investigated how perception of a somatosensory stimulus differed according to whether it was delivered to a limb being prepared for movement or to a nonmoving limb. Our results demonstrate that individuals perceive a somatosensory stimulus delivered to the "moving" limb as occurring significantly later than when an identical stimulus is delivered to a "nonmoving" limb. Furthermore, human brain imaging (fMRI) analyses demonstrate that this modulation is accompanied by a significant decrease in BOLD signal in the right parietal operculum (SII) for stimuli delivered to the moving limb. These results indicate that during movement preparation a network of premotor brain areas may facilitate movement execution by attenuating the processing of behaviorally irrelevant signals within higher-order secondary somatosensory (SII) areas.

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This investigation was inspired by growing evidence that middle-aged persons in a cognitively demanding profession might be characterized by subtle cognitive fatigue. We studied young and middle-aged male schoolteachers. They were compared in a study with functional magnetic resonance imaging to evaluate differences during successful memory encoding. The schoolteachers were additionally subjected to an induced fatigue condition involving the sustained performance of cognitively demanding tasks and to a control condition. Results showed age-related brain activation differences underlying behavioral performance including: (1) greater activation in middle-aged vs. young teachers in bilateral prefrontal cortex (PFC) areas; and (2) differential fatigue effects in the left anterior cingulate cortex (ACC) depending on age group. Middle-aged schoolteachers showed decreased ACC activation in the fatigue compared to the control condition, whereas no change in activation was found in young teachers. Findings demonstrate age effects in these middle-aged subjects that are typically found in older adults, specifically in PFC over-activation. Findings also indicate that already in middle age cognitive aging may be associated with greater resource depletion following sustained task performance. The findings underscore the notion that persons in a cognitively demanding profession can experience subtle age effects, which are evident on fMRI and which impact daily functioning. Possible practical implications for middle-aged schoolteachers are discussed.

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The present study investigated qualitative aspects of spatial memory for the parking place of one's car during an incidental visit to a shopping mall. A total of 115 participants (59 men, age range: 19-85 years) performed a number of short tests, designed to measure several aspects of applied spatial memory, prior to leaving a shopping mall in order to return to their car. Gender differences were observed on two aspects of spatial memory. First, women reported more landmarks in their route descriptions than men, whereas men used metric terms more often than women. Second, men outperformed women with respect to estimating the distance to their car. A main effect of age was observed for map location reconstruction: Older participants had more difficulty in relocating their car on a map. Overall, participants were fairly good in finding back their car. Only 14% made a substantial detour, most of them women. This searching behaviour appeared to depend on sense of direction as well as on map relocation ability. Participants employed a variety of strategies, but the number of strategies used was not related to the measured aspects of spatial memory. The current results give further insight into spatial memory usage in the real world.