People have always been fascinated by supernatural powers, and mind reading is one of those. Believe it or not, we may be really close to reading minds, reading them by decoding brain activity with the help of science. Brain-reading, then, may be a better term to describe such an exploration. Science has gone so far as to scan a brain and read the mind, including its thoughts, dreams, and even intentions. Reading the mind is no longer a fantasy. It is a reality.
▲ Scientists first use fMRI to scan brains and then they decode the measured brain patterns. Provided by news.standford.edu
Science is only in the initial stage of reading what the brain is thinking, having started only a decade ago. The whole process of brain reading is rather complicated. Scientists first scan and measure changes in the brain using electroencephalography (EEG), which measures electrical activity, and functional magnetic resonance imaging (fMRI), which identifies areas of the brain that are charged with oxygenated blood.
Next, they analyze the measured brain patterns to investigate which areas respond to certain stimuli and in what degree and intensity. Reading and understanding these brain patterns require complex mathematical models of brain function and state-of-the-art, high-speed computing.
▲ Jack Gallant successfully reconstructed what the subjects were seeing by decoding their brains. Provided by cnn.com
Jack Gallant at the University of California, Berkeley, uses these techniques to read what the brain is seeing. In his experiments, Gallant first scans a brain watching a movie. He then decodes the brain activity, finds different brain patterns, and from the patterns that are analyzed and classified, guesses what the participants were seeing. Each stimulus produces a brain pattern, so from the database of a large number of samples, a computer program deduces and actually reconstructs a picture of what the brain is seeing.
Simply put, Gallant has a brain-decoding machine that reads brain signals and turns them into pictures. His research aims to understand the mechanisms of the visual system and further create a model of the processing of visual information in the brain. Gallant has explained that there are difficulties in decoding because even for the same image, an individual’s brain pattern may at times differ. Not only that, visual imagery reconstructed from Gallant’s database is at best vague.
▲ Similarly, researchers from Yale University were able to identify and picture the faces subjects were shown. Provided by static.genspot.com
Researchers at Yale University meanwhile conducted a similar experiment using fMRI machines, reconstructing human faces from brain scans. In the study, brains were scanned while the subjects were shown 300 different faces. The brain patterns were then used to build a computer program that matched the brain activity with specific features of the faces. With the database, the researchers could deduce which face the subjects were viewing when they were shown the faces again.
These are not the first achievements in brain reading. In earlier studies, researchers in the past decades could identify what category of object a person was looking at, how many objects a person was seeing, or what picture a person was viewing – all by decoding brain activity. Yet,only recently has science come so far as to identify and visually reconstruct what the brain is seeing.
What we can do with brain reading today, however, is not exactly what we would call mind reading. Mind reading encompasses identifying the mental state of another, but brain reading does not exactly live up such a definition. While neuroscientists can read what the brain is seeing or thinking under a specific and controlled situation, they have not yet come up with a universal mind reading machine. When given arbitrary subjects and stimuli, mind reading is pretty much impossible.
Currently, brain reading can only identify the visual stimuli the brain has been presented with. This provides scientists a better idea of how visual imagery is interpreted in the brain, but then, images are strictly controlled in the experiments.
Individual differences are one obstacle for creating a more general mind reading model. “Different peoples’ brains code information slightly differently, so you need to learn how a specific individual codes their mental states,” said John-Dylan Haynes, a cognitive neuroscientist at Charité-Universitätsmedizin Berlin. “There is only limited transfer from person to person.”
Other aspects of the brain, working memory and intentions, are harder to predict by scanning the brain. There were attempts to determine what people were dreaming about, for instance from Yukiyasu Kamitani and colleagues at the Advanced Telecommunications Research Institute International in Kyoto, Japan, but the experiment failed to achieve a level of high sophistication. Scientists can currently only read active parts of the brain.
Science has a long way to go if it is to succeed in mind reading just like those supernatural beings on television, and that may be more than a hundred years from now. In the mean time, scanning and reading the brain will help scientists better understand the bewildering workings of the human brain.