Standard therapies for chronic low back pain are pharmacological, psychological, physical and occupational therapies or surgery.

Multifactorial Memory Questionnaire is a self-administered questionnaire that includes 57 items assessing the three dimensions of metamemory: Satisfaction, Ability, and Strategy.

The Adult Executive Functioning Inventory (ADEXI; Holst and Thorell, 2018) is a self-administered questionnaire comprising 14 items that assess subjective perceptions of one's inhibition skills and working memory. Each item is measured on a 5-point Likert scale (from ''definitely not true'' to ''definitely true''). The ADEXI total score ranges from 14 to 70, with higher scores indicating greater subjective impairment in the executive domain.

Quality of Life Assessment Questionnaire (Short Form Health Survey 36, SF-36), which consists of a survey of the patient's health status. It is a 36-item scale, which measures eight domains of health status: physical functioning; physical role limitations; bodily pain; general health perceptions; energy/vitality; social functioning; emotional role limitations and mental health. A scoring algorithm is used to convert the raw scores into the eight dimensions listed above. In addition, it is possible to calculate the values of the two synthetic indices, one related to Physical Health (FHH), and the second to Mental Health (MHSI). The scores are transformed to range from zero where the respondent has the worst possible health to 100 where the respondent is in the best possible health.

The Beck Depression Inventory (BDI) is a self-report instrument to assess the severity of depression. It consists of 21 items, which assess the presence and intensity of depressive symptoms in the past two weeks, which can be assigned 0 to 3 points. The BDI total score ranges from 0 to 63. The cut-off is equal to 16.

The State-Trait Anxiety Inventory (Spielberg et al., 1968) is a self-report instrument to assess the severity of anxiety symptoms. It consists of two scales (Y1 and Y2) of 20 items, which assess state anxiety, through questions referring to how the subject feels at the time of questionnaire administration, and trait anxiety, with questions investigating how the subject habitually feels. The scores for the individual scales range from 20 to 80 with a threshold value predictive of anxiety symptomatology placed at 40.

The Apathy Evaluation Scale (Marin et al., 1991) is a rating scale to assess apathy consisting of 18 items. The total apathy score ranges from 18 to 72 and is given by the sum of the scores obtained at the items assessing cognitive apathy, behavioral apathy, emotional apathy, and items that are part of the other category. The cut-off is equal to 38.

The Numeric Rating Scale is an 11-point unidimensional scale that rates pain intensity. The scale consists of a horizontal line, with a range from 0 to 10, corresponding to "no pain" and "worst pain imaginable," respectively. The total score ranges from 0 to 10, with a high score indicating the presence of a greater intensity of pain.

The Roland Morris Disability Questionnaire is a self-administered questionnaire that assesses the patient's disability and limitations in daily life. It consists of 24 items that assess the subject's ability to perform the 24 listed activities. For each item, a score can be given ranging from 0 (that activity is not limited) to 1 (that activity is limited). The total score ranges from 0 to 24, with high scores indicating the presence of a greater disability.

The Pain Catastrophizing Scale is a scale that assesses catastrophic thinking in relation to pain. It consists of 13 items in which participants are asked to reflect on past painful experiences and to indicate how often certain thoughts and feelings occur when they experience pain. Each item can be given a score ranging from 0 (never) to 4 (always). The total score ranges from 0 to 52, with higher scores indicating a greater presence of catastrophic thoughts.

The Brief Resilience Scale (BRS) is a self-administered scale that assesses resilience in stressful situations through 6 items on a 5-point Likert scale (1=completely disagree; 2=disagree; 3=neither agree nor disagree; 4=agree; 5=completely agree). The total score ranges from 6 to 30, with higher scores indicating greater resilience in stressful situations.

The Pain Self-Efficacy Questionnaire is a questionnaire used to measure perceived self-efficacy with respect to the presence of pain. It consists of 10 items that describe different daily activities (e.g., I can do most housework) or general aspects of life (e.g., I can still accomplish most of my goals). For each item, the subject must indicate how confident he or she feels that can perform these activities despite the presence of pain. The items are measured on a 7-point Likert scale ranging from 0 (not at all confident) to 6 (completely confident). The total score on the questionnaire can range from 0 to 60, with higher scores indicating greater self-efficacy.

The Coping Scale is a self-administered questionnaire that assesses the use of cognitive, emotional, and behavioral strategies in problem situations. The questionnaire consists of 13 items measured on a 4-point Likert scale (1=not at all; 2=little; 3=somewhat; 4=very much). Scores range from 13 to 52, with higher scores indicating greater levels of coping strategies.

Heartbeat Detection Task will be used to investigate interoceptive accuracy. In this task, participants will be asked to count their heartbeats silently only in their minds, without trying to sense their own pulse or heartbeat. They will be asked to wear a wristwatch for objective measurement of heart rate. Three counting phases of 25 sec, 45 sec, and 65 sec durations, interspersed with 30 sec rest, will be carried out and repeated twice. The order of the phases will be randomized. The level of agreement between measured heart rate and reported subjective perception will be considered a relatively reliable characteristic of "interoceptive accuracy."

The Self Awareness Questionnaire will be used to investigate interoceptive sensitivity. It consists of 35 items measured on a five-point Likert scale (0 = never to 4 = always). The total score is the sum of all items and ranges from 0 to 140. Higher scores indicate higher levels of interoceptive awareness.

Interoceptive awareness will be investigated using a self-report measure that assesses the individual perception of the degree of accuracy of perceived interoceptive (cardiac) information. The relationship between objective interoceptive accuracy and subjective assessment of one's interoceptive accuracy is calculated to obtain a metacognitive measure of how the perceived degree of interoceptive accuracy corresponds to objectively measured interoceptive accuracy.