Spoken word mediated interference in a visual task: Eye tracking evidence from bilinguals

Abstract

Listening and speaking constitute two most fundamental aspects of human communication. While speaking is largely intentional and calls for voluntary control and planning, listening could be largely unintentional. One listens and understands speech even when one is not being deliberate. Not much is known about control, attentional mechanisms and intention during listening. Most psycholinguistic studies ask participants to comprehend speech under different task requirements and measure comprehension. However, recently it has been observed that listening without any intention to comprehend can lead to attention capture and change in action plan. This nexus between speech and action control can be very useful in understanding goal planning and cognition in humans. The abundance of speech around us and its evolutionary importance makes it a very important biological stimulus in understanding different facets of control. In this chapter, we will review studies where unintentional comprehension of speech has been shown to cause changes in goal-directed action. We particularly look at studies where eye movements and other such motor actions have been shown to deviate during such multi-modal processing. It appears that speech just cannot be ignored in many situations and this penetrates into processing modules that require no language. We look at visual world studies with bilinguals where listening to words causes slowness in a visual search task.