Table 2.
Experimental studies supporting a neurological etiology of the condition
| Author(s) | Year | Sample size | Clinical features | Limb | Psychological/psychiatric diagnosis | Sexual difficulties | Technique | Task | Results
|
|
|---|---|---|---|---|---|---|---|---|---|---|
| Area | Side | |||||||||
| Brang et al26 | 2008 | n=2 | Mixed (1 bilateral) | Legs | No | No | SCR | Pain perception | Increased SCR response for the to-be-amputated limb | – |
| McGeoch et al3 | 2011 | n=4 | Mixed (1 bilateral) | Legs | No | No | MEG | Tactile stimulation | SPL (reduction of activity) Intact visual and somatosensory cortices | R |
| Aoyama et al28 | 2012 | n=5 | Unilateral | Legs | No (psychiatric, neurological and neuropsychological examination) | No | Psychophysics (just noticeable difference + Points of subjective simultaneity) | Temporal order judgment of tactile stimuli | Altered integration of tactile stimuli on the to- be-amputated leg | – |
| Hilti et al30 | 2013 | n=13 | Mixed (3 bilateral) | Legs | No (psychiatric, neurological and neuropsychological examination) | No | Surface-based morphometry | No task | SPL IPL Subcentral cortex (SII) Paracentral lobule (SI) Anterior insular cortex |
R |
| IPL SII |
L | |||||||||
| van Dijk et al31 | 2013 | n=5 | Unilateral | Leg + 1 individual (finger) | Yes (1 individual) (DSM-IV axis I and II screening) | No | fMRI | Tactile stimulation + motor execution task | Frontoparietal and occipital network (heightened sensitivity) PM (hypofunction) |
R, Bilateral |
| Lenggenhager et al32 | 2014 | n=13 | Mixed (3 bilateral) | Leg | No | No | CVS | Rating of estrangement + body temperature | No diminishing of desire | No lateralization effects |
| Bottini et al33 | 2014 | n=7 | Mixed (1 bilateral) | Leg/arm | Yes (1 individual) (semi-structured psychiatric interview) | No | Single subject analysis (Crawford t-test) | Facial emotion recognition task + disgust rating task + disgust scale | Altered disgust rating only in unilateral individuals | – |
Abbreviations: DSM, Diagnostic and Statistical Manual of Mental Disorders; SCR, skin conductance responses; MEG, magnetoencephalography; fMRI, functional magnetic resonance; CVS, caloric vestibular stimulation; PM, premotor cortex; SPL, superior parietal lobe; IPL, inferior parietal lobe; SII, secondary somatosensory cortex; SI, primary somatosensory cortex; R, right hemisphere; L, left hemisphere.