Decoding the visual and subjective contents of the human brain

• Published in: Nature neuroscience Vol. 8; no. 5; pp. 679 - 685
• Main Authors: Kamitani, Yukiyasu, Tong, Frank
• Format: Journal Article
• Language: English
• Published: New York Nature Publishing Group US 01.05.2005; Nature Publishing Group
• Subjects: Adult; Algorithms; Animal Genetics and Genomics; Attention - physiology; Behavioral Sciences; Biological Techniques; Biomedical and Life Sciences; Biomedicine; Brain; Brain Mapping - methods; Cognition - physiology; Evoked Potentials, Visual - physiology; Humans; Magnetic Resonance Imaging - methods; Medical examination; Models, Neurological; Neural networks; Neurobiology; Neurosciences; Orientation - physiology; Pattern Recognition, Visual - physiology; Photic Stimulation; Physiological aspects; Visual Cortex - anatomy & histology; Visual Cortex - physiology; Visual Pathways - physiology; Visual perception; Visual Perception - physiology; United States
• ISSN: 1097-6256; 1546-1726
• DOI: 10.1038/nn1444

The potential for human neuroimaging to read out the detailed contents of a person's mental state has yet to be fully explored. We investigated whether the perception of edge orientation, a fundamental visual feature, can be decoded from human brain activity measured with functional magnetic resonance imaging (fMRI). Using statistical algorithms to classify brain states, we found that ensemble fMRI signals in early visual areas could reliably predict on individual trials which of eight stimulus orientations the subject was seeing. Moreover, when subjects had to attend to one of two overlapping orthogonal gratings, feature-based attention strongly biased ensemble activity toward the attended orientation. These results demonstrate that fMRI activity patterns in early visual areas, including primary visual cortex (V1), contain detailed orientation information that can reliably predict subjective perception. Our approach provides a framework for the readout of fine-tuned representations in the human brain and their subjective contents.