Objective
Theory suggests that a tendency to experience distortions in somatosensory awareness is associated with physical symptom reporting (i.e., somatization) but empirical evidence for this is lacking. This article describes research designed to test this hypothesis.
Methods
Somatosensory distortion was operationalized as the frequency of illusory touch experiences (i.e., false alarm rate) on the Somatic Signal Detection Task. Two studies correlated false alarms on this task with physical symptom reporting on the 15-item Patient Health Questionnaire, the first using a nonclinical sample (n = 35), the second using a clinical sample of endoscopy patients who were identified as having either medically explained (n = 25) or medically unexplained symptoms (n = 30).
Results
Scores on the 15-item Patient Health Questionnaire were positively correlated with false alarm rate in both studies (r = 0.288–0.506), even after controlling for trait anxiety, depression, anxiety (standardized β range = 0.793–0.932, all p < .0001) and (in Study 2) somatosensory amplification and hypochondriacal worry (standardized β range = 0.345–0.375, both p < .05). There was no difference in false alarm rate between patients with medically explained and medically unexplained symptoms (medically explained median range = 6.8 [3.7] to 6.8 [4.0] versus medically unexplained median range = 4.3 [3.9] to 5.6 [3.1], both p > .1).
Conclusions
There seems to be a robust link between physical symptom reporting and the tendency to experience somatosensory distortion, consistent with recent cognitive theories. It may be possible to reduce the impact of somatization by developing treatments that target this tendency.
Abbreviations
MUS = medically unexplained symptom
SSDT = Somatic Signal Detection Task
NA = negative affectivity
SSAS = Somatosensory Amplification Scale
PHQ = Patient Health Questionnaire
STAI = State-Trait Anxiety Inventory
HAI = Health Anxiety Inventory
HADS = Hospital Anxiety and Depression Scale
LED = light-emitting diode
