Cognitive functions play a fundamental role in a planning and organizing the behaviors and emotions in order to elaborate schemes in response to certain conditions. These cognitive abilities are connected to numerous aspects of life, and in sport they play a decisive role in individual and collective performance. In a combat sport like karate, they are fundamental and it is important to check how they are influenced by sport-specific training. Eleven international level karatekas were enrolled in the experimental study and a pre-post technical training evaluation protocol was developed. During the evaluation sessions a photocell system was used to evaluate cognitive performance in terms of response times, visual attention and brain speed. Response times were analyzed at two levels of difficulty with dominant and non-dominant limbs, and number of correct answers, errors and levels achieved were taken into account. A paired sample t-test and a Wilcoxon’s two-sample dependent non-parametric test were performed. The results show an improvement in post-training response times for the easiest difficulty level. For brain speed there is an increase in consecutive correct answers in post-training. No significant differences emerged in the other parameters. These findings can help technicians to implement cognitive exercises during training in order to improve the performance of katatekas.