This disclosure relates generally to testing for purposes of diagnosis and general research in the area of cognitive function, especially with respect to participants with below average abilities to inhibit their actions in response to stimuli. This disclosure also relates to the use of a game scenario to exercise an ability to react to the presentation of a stop-signal by inhibiting the execution of a response to a go-signal presented shortly before. This is known as a Stop-Signal Task. Additional tasks that require inhibitory control such as Differential Reinforcement of Low rates (DRL) or Reversal Learning may be implemented alone or in combination with the Stop-Signal Task in either a testing or imaging implementation or in software used to provide therapeutic exercise of inhibitory control.