Role of familiarity in auditory discrimination of musical instrument: a laterality study

Normal subjects were presented with dichotic pairs of sounds differing in pitch-timbre combination. Their task was to detect a fixed target sound that occurred randomly but equally often in the right and the left ear in two-thirds of the trials. Half the subjects performed this task with sounds produced by familiar natural instruments (violin, flute, guitar and drum), and the other subjects performed the same task but with the sounds played backwards, hence being less recognizable. Subjects were quicker and more accurate in discriminating forwards than backwards played sounds, hence exhibiting sensitivity to familiarity with musical instrument sounds. Recourse to this knowledge was, however, not associated to a shift in laterality. For both familiar and unfamiliar sounds, a robust left-ear advantage (LEA) was observed.