Neurological basis for "Phantom limb" phenomenon:

Ans. d (Law of Projection) (Ref. Ganong Physiology 22nd/pg. 126)Phantom limb is post-op complication of amputation of limb where patient feels amputated limb and sometimes it becomes painful. It is best explained by law of projection.Weber-Fechner LawMagnitude of sensation felt is proportionate to the log of intensity of the stimulusLaw of ProjectionPhantom limb is post-op complication of amputation of limb where patient feels amputated limb and sometimes it becomes painful. It is best explained by law of projection.Bell-Magendie LawThe basic unit of integrated reflex activity is the reflex arc. This arc consists of a sense organ, an afferent neuron, one or more synapses that are generally in a central integrating station, an efferent neuron, and an effector. In mammals, the connection between afferent and efferent somatic neurons is generally in the brain or spinal cord. The afferent neurons enter via the dorsal roots or cranial nerves and have their cell bodies in the dorsal root ganglia or in the homologous ganglia on the cranial nerves. The efferent fibers leave via the ventral roots or corresponding motor cranial nerves.The principle that in the spinal cord the dorsal roots are sensory and the ventral roots are motor is known as the Bell-Magendie law.