Interoceptive aberrations in major depressive disorder: Neural mechanisms, clinical correlates, and targeted interventions

Table 1 Comparison of major interoceptive dimensions and commonly used assessment tools

Dimension (definition)	Tool/method	Measurement	Key advantages/limitations	Target populations	Ref.
IAc: Performance in detecting or discriminating bodily signals	HCT	Agreement between reported and recorded heartbeats	Simple and widely used; influenced by time estimation, heart-rate knowledge, physiology, instructions, and scoring	Clinical and nonclinical adults	[6,26,29-31]
IAc: Performance in detecting or discriminating bodily signals	Heartbeat discrimination tasks	Trial-based discrimination of cardiac signals	Less reliant on explicit counting; sensitive to attention, cardiac signal strength, and task design; limited standardization	Experimental and clinical samples	[5,28,33]
ISe: Self-reported attention to and appraisal of bodily sensations	MAIA/MAIA-2	Multidimensional bodily attention, appraisal, and regulation	Broad multidimensional assessment; reliability and factor structure vary; interpretation may be influenced by alexithymia and cultural context	General and clinical adults, including MDD	[24,25,34,40,68]
ISe: Self-reported attention to and appraisal of bodily sensations	BPQ-SF	Body awareness and perceived autonomic reactivity	Brief and easy to administer; may overlap with somatic or anxiety-related symptoms; does not assess objective accuracy	General, clinical, and cardiovascular samples	[35-37]
IAw: Correspondence between task performance and confidence	Performance-confidence correspondence	Calibration of performance and confidence	Assesses metacognitive insight; depends on task validity and confidence metrics	Studies combining interoceptive tasks with confidence ratings	[4,5,69]

BPQ-SF: Body Perception Questionnaire-Short Form; HCT: Heartbeat counting task; IAc: Interoceptive accuracy; IAw: Interoceptive awareness; ISe: Interoceptive sensibility; MAIA: Multidimensional Assessment of Interoceptive Awareness; MAIA-2: Multidimensional Assessment of Interoceptive Awareness, Version 2; MDD: Major depressive disorder.

Table 2 Evidence for interventions with potential relevance to interoceptive dysfunction in major depressive disorder

Intervention	Evidence base	Key findings	Evidence appraisal	Ref.
Cardiac-musical synchronization	Single-session study in 24 healthy adults	Improved cardiac interoceptive performance; lower HR and negative affect; higher HRV	Small healthy sample; indirect relevance to MDD	[60]
Aerobic exercise	RCT in inactive young adults without MDD	Improved HCT performance and confidence; reduced depressive/anxiety symptoms	Nonclinical sample; HCT-based outcome	[59]
Osteopathic manipulative treatment	Pilot and sham-controlled studies; RCT protocol in chronic low back pain	Improved body awareness/heartbeat tracking; altered interoceptive-region activity	Direct interoceptive evidence outside MDD; depression evidence preliminary	[61,62,67]
Functional electrical stimulation	Uncontrolled pilot in 10 patients with MDD	Reduced depressive symptoms; interoception not assessed	Feasibility evidence in MDD; mechanism untested	[63]
Mindfulness-based interventions	Clinical and controlled studies in depression/anxiety or nonclinical samples	Changes in anterior insula activity and selected MAIA dimensions	Heterogeneous evidence; mainly neural/self-report outcomes	[57,58,64]
Deep brain stimulation	Small mechanistic/longitudinal studies in treatment-resistant MDD	Altered limbic/insula connectivity; HEP increase linked to faster response	Direct neural evidence; very small samples; no performance-based IAc	[65,66]

HCT: Heartbeat counting task; HEP: Heartbeat-evoked potential; HR: Heart rate; HRV: Heart rate variability; IAc: Interoceptive accuracy; MAIA: Multidimensional Assessment of Interoceptive Awareness; MDD: Major depressive disorder; RCT: Randomized controlled trial.