Structural changes in different regions of the brain have become clinically relevant and regarded as the signature phenomenon for neurological diseases. Morphological changes in brain are also associated with neuronal and neurochemical alterations. Studies have showed that minute changes in neurochemical levels may have marked impact on the psychobehaviourof the subject. Several neurological disease profiles have been reported with such specific psychobehavioural expression. However, application of behavioural abnormalities as possible disease progress markers has not been considered and emphasised much. Reports suggestedthat- the subjects, who have already entered into the terminal stage of the disease, used to show cardinal behavioural signs for a specific disease profile. However, psychologicalexpressions are comparatively early expressive. As most of the neurodegenerative disordersare unidirectional and progressive by nature, therapeutic intervention at the right time isessential for attaining the desired outcome. Moreover, early diagnosis can aid in managingthe disease progression also. Psychobehavioural analysis could meet the expected outcomeof disease diagnosis if implemented properly and timely. In the present review, we have amalgamated the reported behavioural anomalies with the supportive background fromneurochemical basis. Further, we have concluded that behaviour centric studies could b ea p ote ntial diagnostic tool for the early diagnosis of major neurological diseases such asAlzheimer disease, Parkinson’s disease, Amyotrophic lateral sclerosis (ALS), Bipolar disorder,Schizophrenia, Impulse control disorder (ICD) and Obsessive-compulsive disorder (OCD).