Amputees for centuries have reported a prolonged presence and feeling of their amputated limb or body part after it has been removed. This phenomenon has preempted what is understood as the phantom limb phenomenon, which is currently accepted as a natural consequence of amputation (Hill, 1999). Most common reports are found amputations of the arms and legs yet reported experiences have been documented post-amputation in other areas such as the breast, penis, eye, teeth and bladder (Giummarra, Gibson, Georgiou-Karistianis, & Bradshaw, 2007; Nicolelis, 2008).
Phantom limb sensation, phantom limb pain and pain in the residual limb are unique areas of this phenomenon and often the terms are misused. Pain in the residual limb is often confused with the phantom phenomenon yet it actually refers to the pain felt in the physical area above the level of amputation (Hill, 1999). However, phantom limb sensation (PLS) is described as any non-painful sensation that is presented where the limb is no longer present (Hill, 1999; Wilkins, McGrath, Finley & Katz, 1998). Conversely, phantom limb pain (PLP) is characterized as burning, tingling, throbbing, cramping, squeezing, shocking or shooting pains experienced where the limb is no longer present (Modirian, Shojaei, Soroush & Masoumi, 2009).
For pain in particular, many treatments have been created to ease the pain, but none have been successful at curing the pain (Modirian et al., 2009). One particularly popular treatment option is that of mirror treatment. In mirror treatment, an individual with an amputation is placed at a table with a mirror that is placed along the individual’s midline (Ramachandran & Rogers-Ramachandran, 2008). With the intact limb symmetrically positioned with the phantom limb, on either side of the mirror, patients are able to look at the reflection of the normal hand in the mirror and are able to visually experience the limb that is missing (Ramachandran & Rogers-Ramachandran, 2008). With this visualization, patients found that they could not only see the phantom hand move but also could feel it move as well (Ramachandran & Rogers-Ramachandran, 2008). As a result, patients were able to relieve their pain temporarily. In 2010, encouraging new treatments involving injection of anesthetics, mixtures of other medicinal and chemical compounds, and non-chemical treatments were reported, suggesting that research is working in a positive direction (Kapoor, 2010).
While amputees continue to report these sensations and pains, researchers and scientists continue to search for explanations as to what causes the experience. In 1981, Linda Dawson and Paul Arnold identified in their article that the mechanisms underlying persistent phantom limb pain was controversial and was dichotomous in nature between the peripheral theory (i.e., pain as a result of nerve endings in stump) and central theory (i.e., pain results from psychological factors separate from sensory processes) (Dawson & Arnold,...