Background: Numerous physiological changes occur in the nervous system with increasing age. On clinical neurological examination, such changes may be misinterpreted as pathology in the nervous system. The objective of this article is to provide a review of the clinical neurological findings that may be caused by normal ageing.
Material and methods: The present manuscript is based on a non-systematic search in PubMed as well as on the clinical experience of the authors.
Results: Cognitive functions are usually fairly well preserved in old age, apart from executive functioning, psychomotor speed and episodic memory, which are reduced with increasing age. Physiological changes related to increasing age include, in particular, vertical eye movements (upwards), vibration sense, Achilles reflexes, primitive reflexes and motor speed. Muscle power is reduced by 20-40% in healthy individuals aged over 70 years.
Interpretation: A correct diagnosis based on findings in the neurological examination cannot be made without knowledge of how ageing affects the physiology of the nervous system. However, the evidence regarding physiological changes in the nervous system is limited, and more research is needed in this field.