Attentional intensity: Phasic alertness in visual perception

• Applicant: Dr. Christian H. Poth
• Subject Area: General, Cognitive and Mathematical Psychology
• Term: from 2020 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 429119715

Human interaction with the environment requires the brain to be in a state of readiness to respond to external information. External stimuli (alerting cues or warning signals) can increase this readiness for short periods, which is referred to as phasic alertness. In perceptual and cognitive tasks, phasic alertness becomes evident as alerting effects of improved performance when target stimuli follow alerting cues compared with when they do not. In contrast to classic views, recent studies revealed that phasic alertness not only speeds up behavioral responding but already enhances the encoding of visual information for perception. Importantly, however, it is not yet understood how this happens and by what bottom-up stimulus-driven and top-down task-driven factors it can be influenced. The present research project addresses these problems in three lines of experimental research, all assessing visual encoding using well-established methods from Bundesen’s (1990) Theory of Visual Attention. The first research line aims to provide a more detailed description of established visual and auditory alerting effects on visual perception, and of important stimulus characteristics modulating the effects. On this basis, the second and third lines then investigate how alerting effects can be influenced in a top-down task-driven fashion. To this end, the second line tests whether and how alerting effects are affected by the attentional priority of the stimuli used as alerting cues. Complementarily, the third line goes on to test whether and how alerting effects are modulated by the attentional priority of the information channels within which alerting cues appear. Taken together, the research project aims to provide a new empirical basis for mechanistic models of phasic alertness and to inform applications where observers receive warning signals for upcoming visual perception.

• DFG Programme: Research Grants
• Co-Investigator: Professor Dr. Werner X. Schneider