Table 1.
Descriptive statistics.
Table 2.
Patients’ clinical information.
Fig 1.
Graphical description of the experimental timeline.
Note: the ‘incidental’ virtual reality task was not part of this project and in the context of the present research merely ensured that sufficient time elapsed between gastric and urinary water loads.
Fig 2.
Novel Urinary Interoceptive Task.
Graphical description of the novel Urinary Interoceptive Task.
Fig 3.
Correlation between the Two-step Water Load and the Urinary Interoceptive Task.
The higher the participants’ gastric interoceptive accuracy (i.e., higher scores indicate higher ability to perceive gastric signals), the higher their urinary interoceptive accuracy (i.e., higher scores indicate higher ability to perceive urinary stimuli). Running correlation analyses separately for each group (healthy controls vs. patients with endometriosis) revealed that the novel urinary task did not correlate with the Heartbeat Counting Task (R = 0.2389, p = 0.2034) but did correlate with the Water Load Test (R = 0.5522, p = 0.001557) in healthy controls. In contrast, in the endometriosis group, there were no significant correlations with either the Heartbeat Counting Task (R = 0.1516, p = 0.4239) or the Water Load Test (R = 0.1357, p = 0.4745).
Fig 4.
T-test to explore differences in the a) cardiac interoceptive task between patients with endometriosis and healthy controls; b) gastric interoceptive task between patients with endometriosis and healthy controls; c) urinary interoceptive task. Higher scores indicate a greater ability to detect interoceptive signals (i.e., cardiac, gastric and urinary). Significance: ‘***’ p ≤ .001; ‘n.s.’ non-significant results.
Fig 5.
Bladder Interoceptive Beliefs.
Non- parametric t-tests to explore differences in a) attention to bladder stimuli between patients with endometriosis and healthy controls (higher scores indicate greater attention towards bladder stimuli); b) interference of bladder stimuli with daily activities (higher scores indicate greater interference of bladder stimuli); c) concern towards bladder stimuli between patients with endometriosis and healthy controls (higher scores indicate greater concern towards bladder stimuli); d) nighttime need to empty the bladder (higher scores indicate higher need to empty the bladder during nighttime); e) daytime need to empty the bladder (higher scores indicate higher need to empty the bladder during daytime).