A normative study of neuropsychological performance of adult male population of Turkey

Abstract

Cognitive and motor skills of people are needed in designing ergonomic products and human-work and human-technology systems. These skills, which may vary across the populations of the world, are measured by neuropsychological tests. Some developed countries have already generated normative data of their populations. In Turkey, although there are several related studies, a comprehensive normative data does not exist. For the purpose, the main aims of this study were: (i) Establishing a normative database of neuropsychological performances for the adult male population of Turkey in four main areas (attention, concentration and speed, memory and learning, intellectual function and motor function); and (ii) investigating the effects of age, education level, marital status and smoking on the performances. Six different neuropsychological tests (Digit Span, Corsi Span, Stroop-Color, Raven, Reaction Time and Purdue Pegboard) are applied to 252 adult male participants aged from 18 to 93 with family origins from different regions of Turkey. Subjects are divided into six age groups (18-30, 31- 40, 41-50, 51-60, 61-70, 71+), four education groups (0-5, 6-12, 13-16, 17+), three income levels (low, medium, high), two marital status groups (married/single) and two smoker groups (smoker/non-smoker). As a result, a normative database is established. The results show that memory, learning, attention and decision-making abilities decrease gradually after the age of 50. It has been observed that motor function performance decrease with age. Education has a positive effect on all the performances. Marital status and smoking habits have no effect on the performances. When compared to the other nationalities, the neuropsychological performance of male population of Turkey, in general, is similar to Australian and Italian and lower than Chinese, Korean and the US samples. The established database may serve a reference guide for ergonomic designs as well as clinical applications.