Department of Clinical Neurophysiology, University of Turku, Turku, Finland; Turku Brain and Mind Centre, University of Turku, Turku, Finland; Department of Psychology, University of Turku, Turku, Finland.
Turku Brain and Mind Centre, University of Turku, Turku, Finland; Department of Psychology, University of Turku, Turku, Finland.
Neurosci Biobehav Rev. 2021 Aug;127:353-364. doi: 10.1016/j.neubiorev.2021.04.038. Epub 2021 May 8.
The visual pathways that bypass the primary visual cortex (V1) are often assumed to support visually guided behavior in humans in the absence of conscious vision. This conclusion is largely based on findings on patients: V1 lesions cause blindness but sometimes leave some visually guided behaviors intact-this is known as blindsight. With the aim of examining how well the findings on blindsight patients generalize to neurologically healthy individuals, we review studies which have tried to uncover transcranial magnetic stimulation (TMS) induced blindsight. In general, these studies have failed to demonstrate a completely unconscious blindsight-like capacity in neurologically healthy individuals. A possible exception to this is TMS-induced blindsight of stimulus presence or location. Because blindsight in patients is often associated with some form of introspective access to the visual stimulus, and blindsight may be associated with neural reorganization, we suggest that rather than revealing a dissociation between visually guided behavior and conscious seeing, blindsight may reflect preservation or partial recovery of conscious visual perception after the lesion.
绕过初级视皮层（V1）的视觉通路通常被认为在没有意识视觉的情况下支持人类的视觉引导行为。这一结论主要基于对患者的发现：V1 损伤会导致失明，但有时会保留一些视觉引导行为完好无损——这被称为盲视。为了研究盲视患者的发现在多大程度上可以推广到神经健康个体，我们回顾了试图揭示经颅磁刺激（TMS）诱导盲视的研究。一般来说，这些研究未能在神经健康个体中证明完全无意识的盲视样能力。一个可能的例外是 TMS 诱导的刺激存在或位置的盲视。因为患者的盲视通常与某种形式的对视觉刺激的内省访问有关，并且盲视可能与神经重组有关，所以我们认为，盲视可能反映了损伤后意识视觉感知的保留或部分恢复，而不是揭示视觉引导行为和意识视觉之间的分离。
