Phantom limb phenomenon is best explained by?
High-Yield Explanation
Ans. d (Law of projection). (Ref: Ganong Physiology 22nd ed. 126)LAW OF PROJECTION- 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.- No matter where a particular sensory pathway is stimulated along its course to cortex, the sensation produced is reffered to location of receptor. This principle is called law of projection, e.g., phantom limb & cortical stimulation during neurosurgical procedure on conscious patient.WEBER FESCHNER LAW- Magnitude of sensation felt is proportionate to the log of intensity of the stimulus.BELL-MAGENDIE LAW- The basic unit of integrated reflex activity is the reflex arc. This arc consists of a sense organ, an afferent neuron, one or more synapses, which are generally in a central integrating station, an efferent neuron, and an effector.- 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.- 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.