Interoception and Body Scan

Percentage of completed daily sessions during the 7-day intervention

Meditation-Related Adverse Effect Scale - Mindfulness-Based Program. It includes 11 dichotomic items (yes/no questions), so scores ranges from 0 to 11, with higher scores indicating more adverse effects

Treatment Satisfaction Scale. It includes 5 items rated on Likert-point scale ranging from 0 to 10. Thus, total scores range from 0 to 50, with higher scores indicating greater acceptability of the intervention

Practice Quality-Mindfulness. It consists of 6 items rated on a visual analogue scale ranging from 0 to 100, with higher scores reflecting a higher level of practice quality.

Multidimensional Assessment of Interoceptive Awareness-2. It consists of 37 items rated on a 6-point Likert scale, with higher values indicating a more adaptive and healthier interoceptive sensibility style (healthier approach to internal bodily signals).

Interoceptive Sensitivity and Attention Questionnaire. It consists of 17 items rated on a 5-point Likert scale, ranging from 1 (totally disagree) to 5 (totally agree). Higher scores reflect greater sensitivity to bodily sensations

Perceived Body Boundaries Scale. It is visual analogue scale that depicts seven human bodies, ranging from almost imperceptible at the left pole (labeled "my body boundaries are almost imperceptible") to extremely salient at the right pole (labeled my body boundaries are extremely salient"). Scores can range from 0 to 15.5, with higher scores indicating greater salience in perceiving body boundaries.

Spatial Frame of Reference Continuum. It is a visual analogue scale depicting five concentric circles surrounding the outline of a human figure, and individuals are asked to indicate how far they feel that their self extends beyond their physical body. Scores range from 1 to 6, with higher scores reflecting a more allocentric (vs. egocentric) frame of reference.

Short form of the Five Facet Mindfulness Questionnaire. It is a 15-item instrument that measures the tendency to be mindful in daily life. Items are rated on a 5-point Likert scale, from 1 (never or very rarely true) to 5 (very often or always true). It includes the following dimensions: observing, describing, acting with awareness, non judging internal experience, and non reactivity to internal experience. Higher scores indicate higher levels of the corresponding mindfulness dimension.

The Perth Alexithymia Questionnaire Questionnaire-Short Form. It includes 7 items rated on a 7-point Likert scale (1=strongly disagree; 7=strongly agree), with higher scores indicating higher levels of alexithymia

Short-form version of the Difficulties in Emotion Regulation Scale. It is an 18 item questionnaire that measures the degree of difficulty in regulating emotions. Items are rated on a 5 point Likert scale, ranging from 1 (almost never) to 5 almost always). It includes the following dimensions: (1) lack of emotional awareness of one's own emotions; (2) self reported difficulty in completing tasks and concentrating in the presence of negative emotions; (3) limited access to regulatory strategies that the in dividual perceives as effective; (4) nonacceptance of negative emotional states; (5) self reported difficulty in controlling one's behavior in the presence of negative emotional states, and (6) lack of emotional clarity, i.e., limited knowledge and clarity about one's emotional states. Higher scores indicate higher difficulties in regulating emotions.

Responses to Positive Affect Questionnaire. It is a 16 item questionnaire that measures responses to positive moods, including dampening (i.e., thoughts that are likely to dampen positive emotional states), self focused positive rumination (i.e., rumination on aspects of the self and the pursuit of goals relevant to the self), and emotion focused positive rumination (i.e., rumination on positive mood). Items are rated on a 4 point Likert scale, ranging from 1 almost never ) to 4 almost always ), with higher scores reflecting a greater use of such strategy.

Patient Health Questionnaire-9. It consists of 9 items, which are rated on a 4-point Likert scale, ranging from 0 (never) to 4 (almost every day). Higher scores indicate greater severity of depressive symptoms.

Ad-hoc open-ended questions: ended questions: (1) "Do you think that participating in this study has helped you learn something or become aware of something? If so, what did you learn?"; (2) Do you think that doing the meditation practice has helped you improve anything? If so, what benefits have you noticed noticed?"; (3) Does this practice make sense to you, and why? "; (4) Please describe the sensations, thoughts and/or feelings you have had while doing the meditation practice "; (5) What difficulties have you found when doing the meditation practice?"; (6) What did you like most about the meditation practice? And what did you like the least?", and (7) What do you think is the objective or hypothesis of the study?".