Three different methods to determine intramyocellular lipid (IMCL) contents in human skeletal muscle have been compared. (1)H-magnetic resonance spectroscopy (MRS) was evaluated against electron microscopic morphometry and biochemical assays of biopsy samples from m. tibialis anterior of 10 healthy subjects. The results of (1)H-MRS and morphometry were strongly correlated, proving the validity of the (1)H-MRS results for the noninvasive determination of IMCL. Biochemical assays yielded results that did not significantly correlate with the results of the other methods. When IMCL levels obtained from the three methods are expressed in common units, it was found that (1)H-MRS yielded IMCL average levels that were 1.8 times lower than those found by morphometry. Potential reasons for the discrepancy are discussed. It is expected that (1)H-MRS will be suitable to replace invasive techniques for IMCL determination, whenever noninvasiveness is crucial, e.g., for repeated investigations in studies of substrate recruitment and recovery in exercise.

In retrospective memory, performance predictions have been found to enhance performance on subsequent memory tests. In prospective memory, the influence of metacognitive judgments on performance has not been investigated systematically. In the present study, 140 undergraduate students performed a complex short-term memory task that included a prospective memory task. Half of them gave performance predictions after the prospective memory task instructions. In addition, the specificity of the prospective memory task was manipulated by instructing participants either to perform an action when a word that belongs to the category of musical instruments was presented or to respond when the word "trumpet" was presented. The results showed that performance predictions enhanced performance, but only for the categorical task. Additional analyses of retrieval experience showed that performance predictions lead to an increase in search experiences while cue specificity was accompanied by an increase in pop up experiences. The results indicate that performance predictions can improve prospective performance and thus may be a valuable strategy for assisting prospective memory.

Performing a prospective memory task repeatedly changes the nature of the task from episodic to habitual. The goal of the present study was to investigate the neural basis of this transition. In two experiments, we contrasted event-related potentials (ERPs) evoked by correct responses to prospective memory targets in the first, more episodic part of the experiment with those of the second, more habitual part of the experiment. Specifically, we tested whether the early, middle, or late ERP-components, which are thought to reflect cue detection, retrieval of the intention, and post-retrieval processes, respectively, would be changed by routinely performing the prospective memory task. The results showed a differential ERP effect in the middle time window (450–650 ms post-stimulus). Source localization using low resolution brain electromagnetic tomography analysis suggests that the transition was accompanied by an increase of activation in the posterior parietal and occipital cortex. These findings indicate that habitual prospective memory involves retrieval processes guided more strongly by parietal brain structures. In brief, the study demonstrates that episodic and habitual prospective memory tasks recruit different brain areas.

This indicates that amnesic patients have residual prospective memory capacities and that providing immediate feedback is a promising strategy to draw on these capacities.

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