How to study subjective experience in an animal model of blindsight?

• Published in: Neuroscience research Vol. 201; pp. 39 - 45
• Main Authors: Yu, Xiyao, Yamaguchi, Reona, Isa, Tadashi
• Format: Journal Article
• Language: English
• Published: Ireland Elsevier B.V 01.04.2024
• Subjects: Animals; Awareness; Blindsight; Consciousness; Humans; Models, Animal; Monkey; Saccade; Subjective experience; V1 lesion; Visual awareness; Visual Cortex; Visual Perception; Visual awareness; Saccade; Blindsight; V1 lesion; Subjective experience; Monkey
• ISSN: 0168-0102; 1872-8111
• DOI: 10.1016/j.neures.2023.09.001

The nature of subjective conscious experience, which accompanies us throughout our waking lives, and how it is generated, remain elusive. One of the challenges in studying subjective experience is disentangling the brain activity related to the sensory stimulus processing and stimulus-guided behavior from those associated with subjective perception. Blindsight, a phenomenon characterized by the retained visual discrimination performance but impaired visual consciousness due to damage to the primary visual cortex, becomes a special entry point to address this question. However, to fully understand the underlying neural mechanism, relying on studies involving human patients alone is insufficient. In this paper, we tried to address this issue, by first introducing the well-known cases of blindsight, especially the reports on subjective experience in both human and monkey subjects. And then we described how the impaired visual awareness of blindsight monkeys has been discovered and further studied by specifically designed tasks, as verbal reporting is not possible for these animals. Our previous studies also demonstrated that many complex visually guided cognitive processes were still retained despite the impairment of visual awareness. Further investigation needs to be conducted to explore the relationship between visually guided behavior, visual awareness and brain activity in blindsight subjects. •Blindsight is a special entry point to study the mechanism of subjective experience.•We described how impaired visual awareness was discovered in blindsight monkeys.•We propose our future strategies to clarify the metacognition in blindsight monkeys.