The term "photographic memory" refers to the phenomenon of ________

In intrasubject research, to be considered a single-case experiment, the design must demonstrate covariation of variables, causal time sequence, and

a. strong, positive correlations among all conditions. b. statistically significant F ratios. c. elimination of other plausible causes. d. repetition of conditions using a large number of subjects.

When employing reversal designs in intrasubject research, two problems often occur: 1) the effect of the researcher's intervention may not be reversible; and 2)

a. these designs require many between-subject manipulations b. implementing these AB designs is often expensive. c. it may be unethical to withdraw a beneficial treatment. d. it is difficult to recruit large numbers of subjects required in these designs.