Last Week in Science (12th Nov 2023)

And he could walk again!

Tremors and freezing gait,
do not pass as you wait,
but it is no more your fate.

Parkinson's disease is a condition where neurons of the brain region that controls and coordinates movement start dying. It begins with hand tremors, where the hand shakes uncontrollably, and as the disease progresses other complications follow. One of the symptoms that is seen in the later stages of the disease is difficulty in walking, freezing gate - sudden stopping of muscle movement while walking. This can lead to falls and makes the individual incapacitated. 

A recent case study reports how by providing a neuroprosthesis, an implant in the spinal cord could help an individual with Parkinson's disease to walk without falling. The signals to leg muscle for movement come from the brain via the spinal cord. The researchers had the expertise in controlling these muscle movements via electrical stimulation in the spinal cord controlled by a device that is implanted under the skin and is tuned to provide electric currents to the spinal cord. They had been using this technique to treat paralysed individuals to walk again. The study has been done in a single individual so far but there are plans to initiate a clinical trial to see whether an electrical stimulation in the spinal cord can help other individuals with Parkinson's disease.

Memory and brain cancer

Brain uses a specific type of signalling to learn and store memories. It is because of this signalling that uses growth factors like BDNF, to name one, that connection between brain cells can be modified making learning possible. The neurons and connections that are used more makes the connections stronger by releasing growth factors.

In a surprising and interesting finding, it was reported that cancer cells in the brain, for example glioma also use the same growth factors and signalling to grow and spread (metastasize) inside the brain. What makes this finding important is that if we can stop this signalling between cancer cells, it can help in treating cancers like glioma.

Written (not) by ChatGPT

After the popularity of chatGPT, a large language model trained on existing text data available online, the biggest challenge was to identify whether a certain piece of text has been written by ChatGPT or not. While the makers of such AI tools came up with their own algorithms and and models to find ChatGPT / other AI generated text - so called AI detectors like ZeroGPT, the detection rate was 35 - 65%, i.e it can correctly identify a text piece written by AI only 3 - 6 times out of 10. 

The current study reports an AI detector with a detection rate of 98 - 100%. So, what was different this time? The authors of the study used a specialized text, Chemistry journal articles to train their AI detector to learn. We hope similar tools would be created in the future to reduce instances of cheating and plagiarism.