Brain damage or disruption to the primary visual cortex sometimes produces blindsight, a striking condition in which patients lose the ability to consciously detect visual information yet retain the ability to discriminate some attributes without awareness. Although there have been few demonstrations of somatosensory equivalents of blindsight, the lesions that produce “numbsense,” in which patients can make accurate guesses about tactile information without awareness, have been rare and localized to different regions of the brain. Despite transient loss of tactile awareness in the contralateral hand after transcranial magnetic stimulation (TMS) of the primary somatosensory cortex but not TMS of a control site, 12 participants (six female) reliably performed at above-chance levels on a localization task. These results demonstrating TMS-induced numbsense implicate a parallel somatosensory pathway that processes the location of touch in the absence of awareness and highlight the importance of primary sensory cortices for conscious perception.

大脑损伤或初级视觉皮层的破坏有时会导致盲视，这是一种惊人的情况，患者失去有意识地检测视觉信息的能力，但仍保留在没有意识的情况下区分某些属性的能力。尽管几乎没有关于盲视的体感等效物的证明，但产生“麻木感”（患者可以在没有意识的情况下对触觉信息做出准确猜测）的病变很少见，并且局限于大脑的不同区域。尽管在对初级躯体感觉皮层进行经颅磁刺激 (TMS) 而不是对照部位的 TMS 后，对侧手的触觉意识暂时丧失，但 12 名参与者（6 名女性）在定位任务中以高于机会的水平可靠地执行。