A simple computer-based method for performing and analyzing intracranial self-stimulation experiments in rats.

Intracranial self-stimulation (ICSS) in the rat is a useful tool for studying the importance of various brain monoamines in positive reinforcement. The effects of compounds interacting with dopaminergic neurotransmission is measurable by studying the changes of reward thresholds. By computerisation of the analysis of these thresholds, standardisation and reproducibility is greatly enhanced. The use of an object-oriented programming language simplifies the programming of a specific application and it provides scientists without formal training in computer programming the means to create their own software. A system for the acquisition, execution, analysis and storage of ICSS experiments is described. The hardware is based on Apple Macintosh computers, interfaced to the test chambers and physiological stimulators using a plug-in card supporting A/D, D/A, digital I/O and timer functions. The software written in G (LabVIEW) provides the user with a graphically based 'Virtual Instrument' performing all aspect of the ICSS experiment. The software performs threshold analysis immediately after completion of the ICSS experiment, thereby greatly reducing the total time previously needed to evaluate these experiments. The graphical approach used in LabVIEW allows the programmer to make fast and simple alterations to suit different experimental problems.