Dynamic adjustments in working memory in the face of affective interference.

Cognitive control, which allows for the selection and monitoring of goal-relevant behavior, is dynamically upregulated on the basis of moment-to-moment cognitive demands. One route by which these demands are registered by cognitive control systems is via the detection of response conflict. Yet working memory (WM) demands may similarly signal dynamic adjustments in cognitive control. In a delayed-recognition WM task, Jha and Kiyonaga (Journal of Experimental Psychology: Learning, Memory, & Cognition, 36(4), 1036-1042, 2010) demonstrated dynamic adjustments in cognitive control via manipulations of mnemonic load and delay-spanning cognitive interference. In the present study, we aimed to extend prior work by investigating whether affective interference may similarly upregulate cognitive control. In Experiment 1, participants (N = 89) completed a delayed-recognition WM task in which mnemonic load (memory load of one vs. two items) and delay-spanning affective interference (neutral vs. negative distractors) were manipulated in a factorial design. Consistent with Jha and Kiyonaga, the present results revealed that mnemonic load led to dynamic adjustments in cognitive control, as reflected by greater performance on trials preceded by high than by low load. In addition, we observed that affective interference could trigger dynamic adjustments in cognitive control, as evinced by higher performance on trials preceded by negative than by neutral distractors. These findings were subsequently confirmed in Experiment 2, which was a pre-registered replication study (N = 100). Thus, these results suggest that in addition to dynamic adjustments as a function of mnemonic load, affective interference, similar to cognitive interference (Jha & Kiyonaga Journal of Experimental Psychology: Learning, Memory, & Cognition, 36(4), 1036-1042, 2010), may trigger dynamic adjustments in cognitive control during a WM task.

Distinct and common cerebral activation changes during mental time travel in relapsing-remitting multiple sclerosis patients.

Mental time travel (MTT) entails the ability to mentally travel into autobiographical memory (AM) and episodic future thinking (EFT). While AM and EFT share common phenomenological and cerebral functional properties, distinctive characteristics have been documented in healthy and clinical populations. No report, to our knowledge, has informed on the functional underpinnings of MTT impairment in multiple sclerosis (MS) patients, hence the aim of this work. We studied 22 relapsing-remitting MS patients and 22 matched controls. Participants underwent an AM/EFT assessment using the Autobiographical Interview (Levine et al. 2002), followed by a functional MRI session. The latter consisted in AM and EFT tasks, distinguishing the construction and elaboration phases of events. The results showed impaired performance for AM and EFT in patients, accompanied by increased cerebral activations mostly located in the frontal regions, which extended to the parietal, lateral temporal and posterior regions during AM/EFT tasks, relative to healthy controls. Enhanced brain activations in MS patients were particularly evident during the EFT task and involved the hippocampus, frontal, external temporal, and cingulate regions. The construction phase required greater fronto-parieto-temporal activations in MS patients relative to both healthy controls, and the elaboration phase. Taking together, our results suggested the occurrence of cerebral activation changes in the context of MTT in MS patients, expressed by distinct and common mechanisms for AM and EFT. This study may provide new insights in terms of cerebral activation changes in brain lesion and their application to clinical settings, considering AM/EFT's central role in everyday life.