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Mahjoub, H.

Publications and source records attributed to Mahjoub, H..

3 recordsLinked to original sources

Behavioral and Neural Correlates of Temperament Traits: Insights from Temperament and Character Inventory and fMRI-Based Choice Tasks

A cognitive conflict that is negatively arousing and results in a divergence in preference attitudes toward the chosen and rejected alternatives occurs when individuals are compelled to choose between alternatives that are similarly preferable. This phenomenon, which is frequently referred to as "cognitive dissonance," is of interest in the fields of decision neuroscience and psychology. This study examines the behavioral and neural underpinnings of Cloningers temperament traits--Novelty Seeking (NS), Harm Avoidance (HA), Reward Dependence (RD), and Persistence (PS)--in a decision-making context.Functional magnetic resonance imaging (fMRI) and a modified free-choice paradigm were used to formalize the effect of Cloninger temperaments on cognitive conflict induced by choice. Behavioral analysis revealed significant individual differences across the four TCI dimensions, highlighting distinct variability in participants responses. Imaging data showed that participants with the highest and lowest scores in each temperament trait exhibited unique brain activation patterns during difficult and easy decision tasks. Notably, novelty-seeking was linked to heightened activation in brain regions associated with exploration and cognitive flexibility, while harm avoidance was associated with emotional processing and conflict detection. These findings provide deeper insights into how personality traits influence both behavior and neural responses during cognitive dissonance and decision-making tasks, offering implications for understanding individual differences in decision-related behaviors. The results of this study confirm the effect of temperaments on the degree of perceived dissonance of people, which can be used in many areas such as consumer behavior in marketing. The reason for this is the hesitancy of customers after purchasing the products. Significance StatementThis study provides novel insights into how Cloningers temperament traits--Novelty Seeking, Harm Avoidance, Reward Dependence, and Persistence--modulate both neural and behavioral responses during decision-making processes. By combining fMRI with a modified free-choice paradigm, we reveal that temperament traits significantly impact cognitive dissonance, with distinct brain activation patterns corresponding to individual differences in decision conflict. These findings enhance our understanding of the neural basis of cognitive dissonance and have practical implications for areas such as consumer behavior, where temperament-driven decision conflict can influence post-purchase attitudes. This research highlights the importance of accounting for personality traits when examining decision-related behaviors and suggests that tailoring strategies based on temperament could improve decision outcomes in various applied fields.

neuroscience↗

The evolution of host resistance to a virus is determined by resources, historical contingency, and time scale

Hosts can often evolve resistance to parasites (and other stressors), but such resistance is generally thought to be constrained by trade-offs with other traits. These trade-offs determine the hosts optimal resistance strategy and whether resistance cycles, diversifies, and/or is maintained in the absence of parasite. However, trade-offs are often inconsistently measured across experiments and can depend on environmental conditions. Here, we extend a selection experiment evolving resistance to viral infection under variable resource quality in the Plodia interpunctella model system to explore the evolutionary conditions leading to an incongruent earlier measurement of costless resistance. We find that environmental resource quality, historical contingency, and the time scale of selection all affect trade-offs in our long-term selection experiment. Specifically, populations selected for resistance with the dual stressor of low resource quality are slowed, but not prevented, from evolving resistance. Second, variation in starting populations or early sampled adaptations led to contingency towards context-dependent resistance. Finally, some costs to resistance observed at early time points were compensated over longer evolutionary time scales. Our work therefore informs perspectives for the predictability of adaptation and how variation in specific evolutionary conditions can alter the evolutionary trajectories of a population towards costly or costless resistance strategies.

evolutionary biology↗

Cardiac remodeling after six weeks of high-intensity interval training to exhaustion in endurance-trained males

High-intensity interval training (HIIT) improves physical performance of endurance athletes, although studies examining its cardiovascular effects are sparse. We evaluated the impact of HIIT on blood pressure, heart rate and cardiac cavities size and function in endurance-trained adults. Seventeen endurance-trained males underwent 24-hour ambulatory blood pressure monitoring (ABPM) and Doppler echocardiography at baseline and after 6 weeks of HIIT. Participants were divided in 2 groups (85% maximal aerobic power (MP); HIIT85, n=8 and 115% MP; HIIT115, n = 9) in order to compare the impact of different HIIT intensities. ABPM and cardiac chambers size and function were similar between groups at baseline. HIIT reduced heart rate (55 {+/-} 8 vs. 51 {+/-} 7 bpm; p= 0.003), systolic blood pressure (SBP; 121 {+/-} 11 vs 118 {+/-} 9 mmHg; p = 0.01), mean arterial pressure (MAP; 90 {+/-} 8 vs 89 {+/-} 6 mmHg; p = 0.03) and pulse pressure (52 {+/-} 6 vs 49 {+/-} 5 mmHg; p = 0.01), irrespective of training intensity. Left atrium (LA) volumes increased after HIIT (maximal: 50 {+/-} 14 vs 54 {+/-}14 ml; p= 0.02; minimal: 15 {+/-} 5 vs 20 {+/-} 8 ml; p = 0.01) in both groups. Right ventricle (RV) global longitudinal strain lowered after training in the HIIT85 group only (20 {+/-} 4 vs. 17 {+/-} 3%, p = 0.04). In endurance-trained males, six weeks of HIIT reduce SBP and MAP and increase LA volumes irrespective of training intensity, whereas submaximal HIIT deteriorates RV systolic function.\n\nKey pointsO_LIHigh-intensity interval training improves physical performance of endurance athletes, although studies examining its cardiovascular effects are sparse.\nC_LIO_LIWe evaluated the impact of submaximal (85% maximal aerobic power) and supramaximal (115% maximal aerobic power) high-intensity interval training on ambulatory blood pressure, heart rate and cardiac cavities size and function in endurance-trained adults.\nC_LIO_LIIrrespective of training intensity, six weeks of high-intensity interval training increase left atrial volumes in endurance-trained adults, whereas the submaximal training decreases right ventricular systolic function.\nC_LIO_LIThese results may help identify the exercise threshold for potential toxicity of intense exercise training for at-risk individuals and ideal exercise training regimens conferring optimal cardiovascular protection and adapted endurance training for athletes.\nC_LI

physiology↗