Auditory enhancement of visual phosphene perception: The effect of temporal and spatial factors and of stimulus intensity

NEUROSCIENCE LETTERS

卷:477

Article

Bolognini, Nadia¹  Senna, Irene¹  Maravita, Angelo¹  Pascual-Leone, Alvaro²  Merabet, Lotfi B.² 

[1] Univ Milano Bicocca, Dept Psychol, I-20126 Milan, Italy

[2] Harvard Univ, Beth Israel Deaconess Med Ctr, Dept Neurol, Sch Med,Berenson Allen Ctr Noninvas Brain Stimula, Boston, MA 02215 USA

关键词: Phosphenes;    Multisensory;    Subthreshold;    Auditory;    Visual cortex;    TMS;   

DOI  :  10.1016/j.neulet.2010.04.044

来源: Elsevier

【 摘 要 】

Multisensory integration of information from different sensory modalities is an essential component of perception. Neurophysiological studies have revealed that audiovisual interactions occur early in time and even within sensory cortical areas believed to be modality-specific. Here we investigated the effect of auditory stimuli on visual perception of phosphenes induced by transcranial magnetic stimulation (TMS) delivered to the occipital visual cortex. TMS applied at subthreshold intensity led to the perception of phosphenes when coupled with an auditory stimulus presented within close spatiotemporal congruency at the expected retinotopic location of the phosphene percept. The effect was maximal when the auditory stimulus preceded the occipital TMS pulse by 40 ms. Follow-up experiments confirmed a high degree of temporal and spatial specificity of this facilitatory effect. Furthermore, audiovisual facilitation was only present at subthreshold TMS intensity for the phosphenes, suggesting that suboptimal levels of excitability within unisensory cortices may be better suited for enhanced crossmodal interactions. Overall, our findings reveal early auditory visual interactions due to the enhancement of visual cortical excitability by auditory stimuli. These interactions may reflect an underlying anatomical connectivity between unisensory cortices. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

【 授权许可】

Free