The HDAC inhibitor vorinostat was selected because preliminary data suggest that chronic treatment with vorinostat improves HDAC2-dependent cognitive function in rodent models. Additionally, vorinostat is the first HDAC inhibitor approved by the U.S. Food and Drug Administration (FDA) for the treatment of cutaneous T-cell lymphoma. Dose(s) of vorinostat have been selected based on previous clinical studies in such patients with brain metastasis.