Why in news :
- Scientists at Johns Hopkins University (JHU) recently outlined a plan for a potentially revolutionary new area of research called “organoid intelligence”, which aims to create “biocomputers”.
What are Bio-Computers?
- Biological computers use biologically derived molecules such as DNA and/or proteins to perform digital or real computations.
- The development of biocomputers has been made possible by the expanding new science of nanobiotechnology.
- The term nanobiotechnology can be defined in multiple ways; in a more general sense, nanobiotechnology can be defined as any type of technology that uses both nano-scale materials (i.e. materials having characteristic dimensions of 1-100 nanometers) and biologically based materials.
- Biocomputers use biologically derived materials to perform computational functions.
- A biocomputer consists of a pathway or series of metabolic pathways involving biological materials that are engineered to behave in a certain manner based upon the conditions (input) of the system.
- Biochemical computers use the immense variety of feedback loops that are characteristic of biological chemical reactions in order to achieve computational functionality.
- The JHU researchers’ scheme will combine brain organoids with modern computing methods to create “biocomputers”.
- They have announced plans to couple the organoids with machine learning by growing the organoids inside flexible structures affixed with multiple electrodes (similar to the ones used to take EEG readings from the brain).
- These structures will be able to record the firing patterns of the neurons and also deliver electrical stimuli, to mimic sensory stimuli.
- Recently, scientists were able to grow human neurons on top of a microelectrode array that could both record and stimulate these neurons.
- Brain organoids can also be developed using stem cells from individuals with neurodegenerative or cognitive disorders.
What is the premise of this technology?
- Understanding how the human brain works has been a difficult challenge.
- Traditionally, researchers have used rat brains to investigate various human neurological disorders.
- Now, in a quest to develop systems that are more relevant to humans, scientists are building 3D cultures of brain tissue in the lab, called brain organoids.
- These “mini-brains” (with a size of up to 4 mm) are built using human stem cells and capture many structural and functional features of a developing human brain.
- However, the human brain also requires various sensory inputs (touch, smell, vision, etc) to develop into the complex organ it is, and brain organoids developed in the lab aren’t sophisticated enough.
- They also do not have blood circulation, which limits how they can grow.
Study of the brain :
- Recently, scientists transplanted these human brain organoid cultures into rat brains, where they formed connections with the rat brain, which in turn provided circulating blood.
- Since the organoids had been transplanted to the visual system, when the scientists showed the experimental rats a light flash, the human neurons were activated, too, indicating that the human brain organoids were also functionally active.
- However, human brain organoids are still nested in the rat-brain microenvironment.
- The effects of drugs in this model will have to be interpreted through various behavioural tests in rats, which could be insufficiently representative.
- Therefore, we need to address the limitations of lab-grown organoids and develop a more human-relevant system.
Commercial use of Bio-Computers :
- Currently, brain organoids have a diameter of less than 1 mm and have fewer than 1,00,000 cells (both on average), which make it roughly three-millionth the size of an actual human brain.
- So scaling up the brain organoid is key to improving its computing capacity.
Syllabus : Prelims + Mains; GS 3- Science and Technology