While many labs have quantified behavior in rodents and determined rates of metabolic activity in brain regions, few have attempted to relate the two measures statistically. The work reported here is the correlation of locomotor activity (determined using a photobeam box) and stereotypic behavior (determined from videotapes, using Noldus software) with rates of glucose metabolism in components of the nigro-striatal and mesolimbic systems (determined using the quantified deoxyglucose method).

The subjects were given cocaine during a critical period of brain development and then challenged with a selective D1 dopamine agonist, SKF 82958, while their behavior and brain metabolism were determined. Rates of metabolism were correlated with stereotypic and locomotor behaviors using Pearson Product Moment Correlations. The analysis revealed that, under saline challenge conditions in control rats, rates of metabolism in mesolimbic regions were significantly coupled to rates of locomotor activity. In cocaine-treated rats, however, these correlations tended to be negative. Following SKF challenge, a different pattern was seen: locomotor activity was negatively correlated with mesolimbic metabolism in controls, but positively correlated with it in cocaine-treated rats. Similarly, stereotypic behavior was negatively correlated with nigro-striatal metabolism in controls, but positively correlated in cocaine-treated rats.

In summary, stereotypic and locomotor behavior can certainly be correlated with regional brain metabolism, and these correlations can be both positive and negative in controls. Furthermore, the coupling of metabolism and behavior can be disrupted by developmental exposure to psychostimulants.

Supported by United States NIH grant DA 10990.

Paper presented at Measuring Behavior 2002 , 4^th International Conference on Methods and Techniques in Behavioral Research, 27-30 August 2002, Amsterdam, The Netherlands

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