We describe some characteristics of persistent musical and verbal retrieval episodes, commonly known as "earworms." In Study 1, participants first filled out a survey summarizing their earworm experiences retrospectively. This was followed by a diary study to document each experience as it happened. Study 2 was an extension of the diary study with a larger sample and a focus on triggering events. Consistent with popular belief, these persistent musical memories were common across people and occurred frequently for most respondents, and were often linked to recent exposure to preferred music. Contrary to popular belief, the large majority of such experiences were not unpleasant. Verbal earworms were uncommon. These memory experiences provide an interesting example of extended memory retrieval for music in a naturalistic situation.

We explored the ability of older (60-80 years old) and younger (18-23 years old) musicians and nonmusicians to judge the similarity of transposed melodies varying on rhythm, mode, and/or contour (Experiment 1) and to discriminate among melodies differing only in rhythm, mode, or contour (Experiment 2). Similarity ratings did not vary greatly among groups, with tunes differing only by mode being rated as most similar. In the same/different discrimination task, musicians performed better than nonmusicians, but we found no age differences. We also found that discrimination of major from minor tunes was difficult for everyone, even for musicians. Mode is apparently a subtle dimension in music, despite its deliberate use in composition and despite people's ability to label minor as "sad" and major as "happy."

Four experiments explored an asymmetry in the perceived similarity of melodies: If a first-presented melody is "scalar" (conforms to a diatonic major scale), and is followed by a second melody slightly altered to be " nonscalar" (deviating from a diatonic major scale), subjects judge similarity to be lower than if the nonscalar melody comes first. Experiment 1 produced evidence that asymmetric similarity is not due simply to more strongly scalar melodies having greater memorability. Experiment 2 ruled out the hypothesis that asymmetric similarity depends on a taskspecific strategy reflecting demand characteristics. Experiments 3 and 4 replicated asymmetric similarity while controlling the number of onesemitone intervals in scalar versus nonscalar melodies. The data are consistent with Garner's principles that stimuli are perceived with reference to sets of alternatives and that good stimuli have few alternatives. Specifically, when melodies are presented in scalar—nonscalar order, but not when presented in nonscalar-scalar order, the first melody evokes a small set of alternatives which the second melody often violates.