How effortful is cognitive control? Insights from a novel method measuring single-trial evoked beta-adrenergic cardiac reactivity

The ability to adjust attentional focus to varying levels of task demands depends on the adaptive recruitment of cognitive control processes. The present study investigated for the first time whether the mobilization of cognitive control during response-conflict trials in a flanker task is associated with effort-related sympathetic activity as measured by changes in the RZinterval at a single-trial level, thus providing an alternative to the pre-ejection period (PEP) which can only be reliably measured in ensemble-averaged data. We predicted that response conflict leads to a physiological orienting response (i.e. heart rate slowing) and increases in effort as reflected by changes in myocardial beta-adrenergic activity (i.e. decreased RZ interval). Our results indeed showed that response conflict led to cardiac deceleration and decreased RZ interval. However, the temporal overlap of the observed heart rate and RZ interval changes suggests that the effect on the latter reflects a change in cardiac pre-load (Frank-Starling mechanism). Our study was thus unable to provide evidence for the expected link between cognitive control and cardiovascular effort. However, it demonstrated that our single-trial analysis enables the assessment of transient changes in cardiac sympathetic activity, thus providing a promising tool for future studies that aim to investigate effort at a single-trial level

Physiological synchrony is associated with attraction in a blind date setting

Action Contro

Physiological synchrony is associated with cooperative success in real-life interactions

Cooperation is pivotal for society to flourish. To foster cooperation, humans express and read intentions via explicit signals and subtle reflections of arousal visible in the face. Evidence is accumulating that humans synchronize these nonverbal expressions and the physiological mechanisms underlying them, potentially influencing cooperation. The current study is designed to verify this putative linkage between synchrony and cooperation. To that end, 152 participants played the Prisoner’s Dilemma game in a dyadic interaction setting, sometimes facing each other and sometimes not. Results showed that synchrony in both heart rate and skin conductance level emerged during face-to-face contact. However, only synchrony in skin conductance levels predicted cooperative success of dyads. Crucially, this positive linkage was strengthened when participants could see each other. These findings show the strong relationship between our bodily responses and social behavior, and emphasize the importance of studying social processes between rather than within individuals in real-life interactions.Action Contro

Clonal cytotoxic T cells are expanded in myeloma and reside in the CD8+CD57+CD28- compartment

The occurrence of clonal T cells in multiple myeloma (MM), as defined by the presence of rearrangements in the T-cell\ud receptor (TCR)–b chains detected on Southern blotting, is associated with an improved prognosis. Recently, with the\ud use of specific anti–TCR-variable-b (anti–\ud TCRVb) antibodies, the presence in MM patients of expanded populations of T cells expressing particular Vb regions was\ud reported. The majority of these T-cell expansions have the phenotype of cytotoxic T cells (CD81CD571 and perforin\ud positive). Since Vb expansions can result from either a true clonal population or a polyclonal response, the clonality of CD81TCRVb 1 T cells was tested by TCRVb\ud complementarity-determining region 3 length analysis and DNA sequencing of the variable region of the TCR. In this\ud report, the CD571 and CD572 subpopulations within expanded TCRVb 1CD81 cell populations are compared, and it is demonstrated that the CD571 subpopulations are generally monoclonal or biclonal, whereas the corresponding CD572 cells are frequently polyclonal. The oligoclonality\ud of CD571 expanded CD81 T cells but not their CD572 counterparts was also observed in age-matched controls, in\ud which the T-cell expansions were mainly CD82. The CD81CD571 clonal T cells had a low rate of turnover and expressed\ud relatively lower levels of the apoptotic marker CD95 than their CD572 counterparts. Taken together, these findings demonstrate that MM is associated with CD571CD81 T-cell clones, raising the possibility that the expansion and accumulation of activated clonal CD81 T cells in MM may be the result of persistent stimulation by tumor-associated antigens, combined with a reduced cellular death rate\ud secondary to reduced expression of the apoptosis-related molecule CD95. (Blood, 2001;98:2817-2827