The current study was designed to investigate the effect of an expected or unexpected sound on performance of a visual perception task. On each trial, listeners were required to indicate whether an arrow presented on a computer screen directly in front of them was pointing to the left or right. The arrow stimulus was immediately preceded by a to-be ignored auditory event that was either a pure tone, the word ‘left’ or the word ‘right’. The probability that the arrow was preceded by a tone, a congruent word, or an incongruent word was manipulated across experiments. Congruent words facilitated classification of the arrow stimulus regardless of whether or not they were expected. Incongruent words slowed classification regardless of whether or not they were expected. These results revealed that both expected and unexpected auditory events receive involuntary semantic processing in a cross-modal oddball task.

The current study was designed to investigate the effect of an expected or unexpected sound on performance of a visual perception task. On each trial, listeners were required to indicate whether an arrow presented on a computer screen directly in front of them was pointing to the left or right. The arrow stimulus was immediately preceded by a to-be ignored auditory event that was either a pure tone, the word ‘left’ or the word ‘right’. The probability that the arrow was preceded by a tone, a congruent word, or an incongruent word was manipulated across experiments. Congruent words facilitated classification of the arrow stimulus regardless of whether or not they were expected. Incongruent words slowed classification regardless of whether or not they were expected. These results revealed that both expected and unexpected auditory events receive involuntary semantic processing in a cross-modal oddball task.