This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Humans form robust long-term memories using well-established neuroanatomical substrates including the hippocampus and surrounding gyri. Despite having a proficient long-term memory system for visual information that relies on similar neuroanatomical regions, there is little evidence that monkeys are able to form long-term memories in the auditory modality. This is a perplexing finding and raises the possibility that long-term auditory memories may be specific to humans and have some functional consequence for the evolution of language. The purpose of this project is to test a chimpanzee on a long-term auditory memory task as a crucial step in determining the evolution of auditory MTS skills, i.e. whether the skill is unique to Hominoids, or specifically human. Subjects were trained to perform an auditory s/d discrimination task but never reached the required criterion in the grant period.