Define symptoms in Nervous system of pernicious anaemia?

Parasthesia (numbness and tingling) occurs in fingers and toes.  Occasionally, there are objective signs of involvement of the spinal cord (vitamin B₁₂ neuropathy). In advanced cases, demyelination of the white fibres d the spinal cord occurs, &affecting first the dorsal column and later the lateral column. Historically, PA was considered to be the major cause of vitamin B₁₂ deficiency, more  recently, it has been suggested that a far more common problem is that of  hypochlorhydria associated with atrophic gustritis, where there is a progressive  reduction, with age, of the ability of the parietal cells to secrete hydrochloric acid.