Overview of research methods: descriptive research, describes behaviour, case studies, naturalistic observation, survey research, correlational studies, examines relationship between/among variables, experimental methods, examines cause and effect relationships. Damaging particular regions of the brain in human subjects: used in conjunction with brain imaging techniques, case studies have contributed greatly to the study of localization of function. Jane goodall"s work demonstrated that chimpanzees exhibit behaviours once thought to be uniquely human: eg. Survey research: based on collecting data using questionnaires or interviews, eg. Because the survey sample was unrepresentative: names obtained using telephone directories, car registrations, and magazine subscription lists, this created a sample biased towards wealthier americans. In truly random sampling, everyone in the population has an equal chance of being sampled. If 50% of a population speak a second language (and you think this is relevant to your research question), ensure 50% of your sample is bilingual.