Professor Stephen Hawking has pleaded with world leaders to keep technology under control before it destroys humanity.
sabato 11 luglio 2015
A team of neuroscientists at Duke University published two separate studies today, one involving rats and the other involving rhesus macaque monkeys, that describe experiments on networks of brains, or Brainets, and illustrate how such networks could be used to combine electrical outputs from the neurons of multiple animals to perform tasks.
In the monkey experiment, Dr Miguel Nicolelis of the Duke University School of Medicine and his colleagues linked the brains of rhesus macaque monkeys, who worked together to control the movements of the arm of a virtual avatar on a digital display in front of them. Each animal controlled two of three dimensions of movement for the same arm as they guided it together to touch a moving target.
In the rodent experiment, the team networked the brains of four rats complete simple computational tasks involving pattern recognition, storage and retrieval of sensory information, and even weather forecasting.
“This is the first demonstration of a shared brain-machine interface (BMI), a paradigm that has been translated successfully over the past decades from studies in animals all the way to clinical applications. We foresee that shared BMIs will follow the same track, and could soon be translated to clinical practice,” Dr Nicolelis said.
To complete the experiments, the neuroscientists outfitted the animals with arrays implanted in their motor and somatosensory cortices to capture and transmit their brain activity.
For one experiment highlighted in the primate article, they recorded the electrical activity of more than 700 neurons from the brains of three rhesus macaque monkeys as they moved a virtual arm toward a target.
In this experiment, each monkey mentally controlled two out of three dimensions of the virtual arm. The monkeys could be successful only when at least two of them synchronized their brains to produce continuous 3D signals that moved the virtual arm. As the animals gained more experience and training in the motor task, the scientists found that they adapted to the challenge.
In the second experiment, Dr Nicolelis and co-authors used groups of three or four rats whose brains were interconnected via microwire arrays in the somatosensory cortex of the brain and received and transmitted information via those wires.
The rats received temperature and barometric pressure information and were able to combine information with the other rats to predict an increased or decreased chance of rain.
Under some conditions, the scientists observed that the rat Brainet could perform at the same level or better than one rat on its own.
“The phenomenon that led to this synchrony may have important biomedical implications. For example, perhaps neurologically disabled people could share healthy brain activity from others and collaboratively perform virtual reality-based neurorehabilitation training exercises,” Dr Nicolelis said.
Arjun Ramakrishnan et al. 2015. Computing Arm Movements with a Monkey Brainet. Scientific Reports 5, article number: 10767; doi: 10.1038/srep10767
Miguel Pais-Vieira et al. 2015. Building an organic computing device with multiple interconnected brains. Scientific Reports 5, article number: 11869; doi: 10.1038/srep11869