Prior probabilities tune attentional bandwidth

Top-down schemas or prior probabilities associated with different auditory objects and their acoustic features are thought to improve auditory scene analysis and auditory object recognition processes. This study focused on whether listeners implicitly track the prior probabilities associated with different tone frequencies, and whether tracking those probabilities modulates attentional bandwidth to improve detection sensitivity. Using the target-probe paradigm, attentional bandwidth for varying levels of probe probability was estimated for 40 listeners. To estimate the attentional bandwidth, probes were presented in a continuous band-pass noise masker at distances of .75, 1.25, 1.75, and 3.75 Equivalent Rectangular Bandwidths from a target frequency of 250 Hz, at varying probabilities of occurrence. All tones were presented at approximately 90% detection when presented alone as measured during a separate thresholding procedure. Results indicate that prior probability plays a role in attentional bandwidth:...