Selective attention and perceptual awareness: Testing the competitive interaction hypothesis

• Applicant: Professor Dr. Hans-Otto Karnath, since 7/2017
• Subject Area: Human Cognitive and Systems Neuroscience
• Term: from 2015 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 271661659

The ability to perceive multiple targets simultaneously can be disrupted after unilateral brain damage that leads to the neuropsychological syndrome of extinction. Extinction is generally seen as a consequence of biased competitive interactions between the ipsilesional and contralesional target stimuli and an exaggeration of the difficulty that neurologically healthy subjects have when asked to attend to multiple targets simultaneously. The overarching goal of this project is to elucidate the mechanisms and anatomy of the modulation of competitive interactions between multiple stimuli for selective attention and perceptual awareness. The existing literature suggests a critical role for either the temporo-parietal junction (TPJ) or the intraparietal sulcus (IPS) in the modulation of competitive interactions between target representations, suggesting that both areas are important for our ability to perceive multiple target simultaneously. However, many questions related to the distinctive contributions of the TPJ versus the IPS still remain. In this renewal proposal, we will pursue the following four goals: 1) We will apply our newly developed multivariate pattern analysis method (MVPA) for lesion data to decode the anatomical network(s) associated with extinction. 2) We will test the prediction from the Theory of Visual Attention (TVA) framework that both an abnormal spatial bias and a pathological reduction of visual short-term memory storage capacity are required to elicit extinction and assess the anatomical source of this predicted interaction between spatial bias and visual short-term memory storage capacity. 3) We will assess the influence of a temporary disruption of neural activity in either the IPS or the TPJ on TVA parameters and extinction-like behaviour in neurologically healthy subjects. 4) We will investigate the TVA parameters modulated by extinction in right hemispheric stroke patients and their relationship with lesion location and stroke recovery.

• DFG Programme: Research Grants
• Ehemalige Antragstellerin: Dr. Bianca de Haan, until 7/2017