The present study provides empirical evidence to support the hypothesis that preschool children's cognitive functions can be developed by virtue of a training tool named COGENT (Cognitive Enhancement Training). We assumed that COGENT (COGEST in Spain) which is embedded in speech and language, will enhance the core cognitive processes that are required for reading acquisition. The participants included 97 students aged four and five, who received COGEST for six months. The two core cognitive processes targeted were simultaneous and successive. These were measured before and after the application of COGEST. Simultaneously, we assessed a control group in the same manner, but it did not receive any COGEST training. Results showed that the COGEST group improved its simultaneous and successive processing performance significantly (p 0.00) with Cohen effect size moderate for simultaneous and small for successive, whereas the control group displayed no such change. The study provides evidence for the effectiveness of COGEST in preschoolers to improve the simultaneous and successive cognitive processes (PASS) involved in reading acquisition and suggests its use as a training programme may help prevent reading difficulties. (author abstract)