Slide Slam S1 Sandbox Series
Synchronized brains: The neurobiological mechanisms for cooperative success
Roksana Markiewicz1, Katrien Segaert1,2, Ali Mazaheri1,2; 1School of Psychology, University of Birmingham, UK, 2Centre for Human Brain Health, University of Birmingham, UK
To achieve successful cooperation, mutual conceptual alignment -a state where the mental representations of individuals are aligned- is needed. Conceptual alignment then leads to mutual understanding where individuals implicitly reach an agreement on the meaning of an idea (Stolk et al., 2016). In order to investigate the neurobiological mechanisms that underlie cooperation, simultaneous electroencephalography activity in two cooperating partners (i.e. EEG hyperscanning) is being recorded in an ongoing study with the EEG data collection having only just started. Non-verbal (task 1) and verbal (task 2) cooperation tasks are used to examine the relationship between brain-to-brain synchrony (i.e. activity in one brain that is correlated with activity in another brain) and the degree of cooperative success (i.e. formation of mutual understanding as measured by successful cooperative performance). More specifically, in task 1 we examine the emergence of non-verbal mutual understanding that leads to cooperative success. Cooperative partners are instructed to synchronise their button presses (press their buttons within 250ms of each other) after hearing an auditory cue. Participants wait a short/medium/long amounts of time after hearing a high/medium/low frequency tones respectively. Cooperative partners need to converge on the meaning of ‘short/medium/long’ by adjusting their responses (i.e. their wait time before pressing the button) based on feedback they receive after each trial. Behavioural pilot data (N=17) of the interpersonal time lag (i.e. normalised time difference between partners’ button presses) were analysed as a function of trial progression throughout the experiment. The interpersonal time lag was negatively correlated with the trial number (r(298) =-.39, p <.001), suggesting that participants were able to learn to cooperate with each other more effectively as the task progressed. Task 2 is exploring the effect of verbal communication on conceptual alignment that leads to cooperative success. During the task, each participant within a dyad has a distinct role. Participant 1 (P1) is presented four (target) symbols, which they describe to participant 2 (P2). P2 is presented six columns with 8 symbols in each column. P2 is to find the (target) column that contains all four symbols (amongst distractor symbols) described by P1 and to say the order that the target symbols appear in in the column (omitting the distractor symbols) from top to bottom. P1 then needs to click on the symbols in the order told by P2. Cooperation is successful when all of the symbols on P1’s screen are clicked in the correct order within the time limit of the trial. For both tasks, we will use phase-lag-based connectivity analysis to examine the brain-to-brain synchrony between the cooperating partners. We predict that the degree of brain-to-brain synchrony will be greater in trials where mutual understanding/ cooperative success is achieved compared to cooperative failure trials.