Slide 33 of 36 Summary and Implications, cont d. Behavioral Scientists are keenly aware of the need for careful control of protocols and standardization of methods, and influences of extraneous variables. Single tasks are not likely to provide strong characterization of complex psychological constructs. Some patterns of genetic influence on behavior can be highly stable. For example, body weight showed larger effect sizes for the strain by site interaction than locomotor activity and ethanol consumption.
Similar findings exist for neuroanatomical measures.