“Cerebellar Mutism” is a challenging problem after resection of pediatric tumors in cerebellar midline structures, with the nucleus fastigii regarded relevant. Although the symptoms are mainly transient, children often have long-term social and cognitive deficits. We already showed that juvenile rats with lesions of the cerebellar fastigial nucleus show behavioral deficits and altered neural activity in the medial prefrontal cortex (mPFC). In our study, we recorded prefrontal neural activity during behavioral testing for attention and decision-making. Rats (lesion [n=9], sham-lesion [n=6], naïve [n=9]) were trained in an auditory three-tone oddball paradigm, where they had to nose poke to a rare target tone, while ignoring a rare distractor and a frequent standard tone of different frequencies. After training, electrodes were implanted in the mPFC, and local field potentials were recorded during testing in the oddball paradigm. Analysis of the event related potentials showed higher amplitudes of the early and late component to the target as compared to the distractor and standard tones (p<0.05). Rats with fastigial lesions overhear the target tone more often than naïve rats. Nevertheless, lesioned rats ignore the standard and distractor tone more efficiently and poke less between trials. This is not a lesion-induced motor deficit, as the reaction time of rats with fastigial lesion do not differ from that of sham-lesioned or naïve controls. Overall, this model provides an opportunity to investigate in more depth auditory processing with regard to attention and decision-making, both in unaffected and in disease models.