Passive and Motivated Perception of Emotional Faces: Qualitative and Quantitative Changes in the Face Processing Network

Emotionally expressive faces are processed by a distributed network of interacting sub-cortical and cortical brain regions. The components of this network have been identified and described in large part by the stimulus properties to which they are sensitive, but as face processing research matures interest has broadened to also probe dynamic interactions between these regions and top-down influences such as task demand and context. While some research has tested the robustness of affective face processing by restricting available attentional resources, it is not known whether face network processing can be augmented by increased motivation to attend to affective face stimuli. Short videos of people expressing emotions were presented to healthy participants during functional magnetic resonance imaging. Motivation to attend to the videos was manipulated by providing an incentive for improved recall performance. During the motivated condition, there was greater coherence among nodes of the face processing network, more widespread correlation between signal intensity and performance, and selective signal increases in a task-relevant subset of face processing regions, including the posterior superior temporal sulcus and right amygdala. In addition, an unexpected task-related laterality effect was seen in the amygdala. These findings provide strong evidence that motivation augmentsco-activity among nodes of the face processing network and the impact of neural activity on performance. These within-subject effects highlight the necessity to consider motivation when interpreting neural function in special populations, and to further explore the effect of task demands on face processing in healthy brains

J Nutr Health Aging

BACKGROUND: Aim: The aim of this study was to explore whether multidomain intervention (MI) and Omega-3 Polyunsaturated Fatty Acids supplementation can modify the cognitive function on elderly according to frail status. METHOD: Data are from a secondary exploratory analysis of the Multidomain Alzheimer Preventive Trial (MAPT), a French community-dwellers aged 70 or over reporting subjective memory complaints, but free from clinical dementia. The multidomain intervention consisted of 2 hours group sessions focusing on three domains (cognitive stimulation, physical activity, and nutrition) and a preventive consultation (at baseline, 12 months, and 24 months). For Omega-3 Polyunsaturated Fatty Acids supplementation, participants took two capsules of either placebo or polyunsaturated fatty acids daily. Linear mixed-model repeated-measures analyses were used including baseline, 6, 12, 24 and 36-month follow-up data to assess between-group differences in the change in cognitive tests over 36 months. RESULTS: The overall mean age of the MAPT study population was 75.25(+/-4.38). A tend toward significant differences in TMT-A were found for the effect of the multidomain intervention on the prefrail group compared to non-frail group. The MI and n3 PUFA program could not significantly have reduced cognitive function in a sample of pre-frailty elders. CONCLUSION: This population-based study in community-dwellers aged 70 years or over suggested that multidomain intervention and n3 PUFA supplementation have not significant effects on cognitive function change in frail older adults with memory complaints. The beneficial effect of multidomain intervention and n3 PUFA supplementation on cognitive function did not differ between frail and nonfrail participants