Creating and executing real-time psychological experiments with sub-millisecond time precision uses a Hierarchical Experiment Spreadsheet (HES) providing a hierarchical data structure and interface. The user adds/modifies experiment levels in a spreadsheet multilevel table representation. New objects and properties are added while maintaining the hierarchical structure of the experiment and prohibiting user corruption of the experiments hierarchical structure. A Time Event Queue Manager (TEQM) provides precision timing using event pre-release synchronization, compensating for timing errors produced by the personal computer operating system and enabling sub-millisecond time precision. Separate microprocessor and embedded software provides an external time base time stamping and event output queuing of events between the subject and host computer; queues and releases host computer stimulus events at future time points; synchronizes host computer clock TEQM clock, displays refresh clocks; and provides an audit of timing precision of all events going to the subject.
Psychology hierarchical experiment spreadsheet with pre-release event time synchronization