This is an interesting one.

Dreams are an alternate world to our reality. Famed psychologist Sigmund Freud described dreams as a way for humans to experience their deepest desires?those that they could not fulfil in real life. However, often we are left wondering what we dreamt about at night. Neuroscientists and sleep scientists are now working on developing technologies that would allow us to record our dreams, and later play them back?the way we look at images or movies.

The greatest challenge to realising this idea is the process of ?extracting? the dream from the human brain. Numerous studies done on dreaming and sleep suggest that theoretically, we should be able to extract dreams from our brains.

How did scientists come up with idea of recording dreams?

In 2011, researchers in a study at Gallant Lab at the University of California, Berkeley, showed the study?s participants videos, such as movie trailers, and later reconstructed the visuals from signals obtained from their brain activity.

The reconstructed video was low-resolution and consisted of rough patterns. However, the scientists improved their technology and published a follow-up study in 2016, CNN reported. The ability to reconstruct images from brain activity aroused interest in dream researchers and sleep scientists, who wondered if dreams could be recorded similarly.

The technology to visualise data obtained from our brain is being continuously developed and honed. In April 2017, a study conducted at the University of Wisconsin-Madison, identified a part of the brain associated with dreaming. According to the researchers involved in the study, the ?posterior cortical hot zone? could help identify if a person is dreaming or not. The hot zone usually has a low-frequency activity associated with it. However, when a person is dreaming, the zone experiences high-frequency activity. Researchers believe that this area of the brain can act as a switch or a light, to indicate if a person is dreaming. In their study, scientists also discovered that parts of the brain responsible for various actions in the awake state functioned similarly in the dream state.

Another study being conducted at the University of Texas showed similar results. The researchers at the university?s Cognitive Neuroscience Lab are using an electromyogram to record nerve impulses in the dream state. The results are promising, and state that the brain works similarly during waking hours and when dreaming. Movements performed in dreams such as walking or moving arms do not happen physically, yet the nerve impulses reach the respective regions of the brain. The researchers are also studying the movements of the mouth and lips to see if similar deductions can be made about speech

What do you need to record dreams?

Recording dreams is the intersection of computer science and neuroscience. The technology to record the activity of the brain is continuously evolving. However a major obstacle is visualising the data obtained and making a sense of it. Yukiyasu Kamitani at Kyoto University believes that the problem can be solved by using big data analytics and artificial intelligence algorithms to decode the data.

Kamitani has successfully used fMRI(functional magnetic resonance imaging) which detects brain activity by looking at blood flow, to reconstruct the images from the data obtained. This data relates to brain activity during the wakeful state. His 2013 study used machine learning and fMRI to show that the brain shows same patterns for visual experiences during the wakeful and the sleep state. He believes that this technology could also be used for reconstructing images of dreams.

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