Separating Responses Based on Demand Characteristics and Phenomenological–Spatial Associations

Previous researchers have found that participants associate higher frequencies with locations that are higher in space and lower frequencies with lower locations, creating a phenomenological-spatial association for the frequency of auditory tones. With such an association, the frequency of an auditory tone could potentially bias movements along multiple axes. This hypothesis was tested. In four experiments, nine frequencies (250-1,250 Hz) were binaurally presented to blindfolded participants (n = 10, 12, 20, & 9; M age = 22 yr.) who indicated the perceived location of the stimuli on a measurement scale oriented in the vertical, the horizontal (Experiment 1), or depth dimension (Experiment 2). In Experiment 3, participants were asked to indicate the perceived location of the frequencies on a two-dimensional vertical board located in front of them. In Experiment 4, participants indicated the perceived location in three-dimensional space. An optoelectronic device recorded at all locations. Analyses of constant error indicated a spatial association in the vertical, horizontal, and depth dimensions when responses were restricted to only one dimension (Experiments 1 & 2). Higher frequencies were perceived to be located higher, farther to the right, and farther away from the body than lower frequencies. However, this spatial association was only exhibited in the vertical dimension when the responses were unconstrained in two dimensions (vertical and horizontal; Experiment 3) and all three dimensions (Experiment 4). Although this spatial association is a robust phenomenon, it appears that the association only biases actions when indicating perceived locations in the vertical dimension during unconstrained responses.