If you are anything like me, you love binging True Crime dramas
after a long, stressful day. However, sometimes these detective shows spark a
little uneasiness in me, because putting the "perp" away all too
often relies on eye-witness accounts of the crime. It's common knowledge that
eye-witness accounts are unreliable, but no other options have been
available, until now. Dan Nemrodov, of the University of
Toronto-Scarborough, has developed a technique to reconstruct images of mental
perceptions of faces using EEG.
EEG, also known as electroencephalography, uses surface electrodes
to monitor the firing activity of millions of neurons in a predetermined brain
region. In this study, subjects' EEG recordings were measured as they were
shown images of faces; these recordings were then used to digitally
reconstitute the mental image in the subjects' brains using an algorithm. This
is possible because when we see an image, "our brains creates a mental
percept, which is essentially a mental impression of that thing," explains
Nemrodov. EEG was used to capture the mental percept and recreate a
representation of how the image was processed in the brain.
Nemrodov has also been able to use fMRI to achieve the same
purpose. fMRI indirectly measures brain activity by tracking oxygen movement in
the bloodstream. When an area of the brain is activated in response to the
visual stimulus, oxygen is dumped into that region, which is registered by the
fMRI machine; this analysis utilizes the BOLD (Blood Oxygen Level Dependent)
Effect. Although fMRI has exceptional spatial resolution, temporal resolution
is key in recreating mental images. Therefore, EEG's superior temporal
resolution makes it the neuroimaging technique of choice for reconstruction
studies.
Implications of this study are immense. In addition to replacing
eye-witness accounts, the ability to map mental representations of visual
stimuli and recreate the images also has a wide range of clinical applications.
This technique could be used in assisting mute individuals to communicate, and
potentially provide an accurate neuronal representation of other brain
processes, such as memory and imagination.
By: Sarah Darnell
This implication of EEG in the use of mapping visual stimuli and possibly becoming the closest thing, clinically, to "mind reading" is interesting and further astonishes me about the realm of A.I. I wonder how efficient using this method would be in crime or forensics. In class we discussed the expensive and time-consuming pitfalls of fMRI and I wonder if Nemrodov's method would be worth it in forensics if it meant there would be ground-breaking evidence discovered by testing individuals involved in a crime.
ReplyDeleteThis actually reminds me of a recent Black Mirror episode that involved a "memory reading machine" used to study eye-witness memories of crimes. It's very interesting to see technology one could only dream of in fiction start being developed in real life! Especially given how useful the technology could be. For example, many people have been falsely accused and punished for crimes they did not commit, so I imagine this could help in rectifying that.
ReplyDeleteGreat article Sarah! I love crime shows. It is amazing how much technology has advanced from the first EEG recording to now being able actually read minds with computer algorithms! It is absolutely amazing that the algorithm is designed to construct images as complex as a human face - which is so far past then just an original shape. Although the article states that this has not been the first time that researchers have reconstructed an image from brain activity, it has been the first time that EEG has been used. This proves that researchers are still so dedicated to studying and developing new techniques in science. It is interesting to see how this discovery could change future, especially involving crime and communication applications. It is exciting to see how this advancement might lead us to discover a better explanation of how the brain works, in terms of our perception, memory, and imagination.
ReplyDeleteThis seems like an incredibly interesting application of EEG and modern neuroscience research. It’s fascinating to learn that our brain responds to every novel stimulus in a unique way. The fact that our brain produces different electrical impulses in response to seeing different faces means that we are one step closer to being able to digitally reproduce our memories, imaginations, or dreams. However, this makes me wonder whether EEG signals, as well as other brain scanning technology (fMRI), can be used to map sound, smell, touch, and other senses in a way that we can recreate others’ experiences through virtual reality. However, regardless of how much we can perfect this technology in the future, we are ignoring the fact that the human brain itself is quite imperfect. We don’t remember faces or memories as well as we think we do, and this technology would be best employed in helping us see others’ individual perceptions of events rather than the reality of those events.
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