u2 AOS2 physics communication poster

How is it possible to perceive sensations from and electrically control a prosthesis following limb loss?

Topic: How is electricity used in the body?

OVERVIEW (click)

Metal conductor

1. Charge carriers in the human body vs. those in metals

Conductors in the body

In a bionic limb, charges are carried in wire conductors, whereas in the body charges are carried in ionic solutions. This section explores the difference between the two.

2. Electrical signal transfer in the nervous system

Neural interface

In order for mind controlled prosthetics to work, there needs to be some kind of communication between the nervous system and the electrical component of the prosthetic. This is called a neural interface.

Source comparison task

3. Action potential

Action potential

Graphic model

Action potentials are short-lasting electrical events across the cell membrane that occur in response to a stimulus. Understanding action potential is key to understanding how messages are transferred through the nervous system.

4. How the Heart beats as an electrical pump

The heart uses electricity to function as a pump, supplying oxygenated blood to the parts of the body that need it.

5. The effects of current through the body

When electricity is used close to the body, there is potential for malfunction that can cause harm to the user through discharge of current through/potential difference across the body. This has the potential to cause limb loss.

6. Varying Electrical skin resistance

Most commercial bionic limbs work through electrode connection with the nervous system. A higher resistance in the body could result in reduced signal quality leading to impaired communication between the prosthesis and the nervous system. This can affect the accuracy, responsiveness, and functionality of the bionic limb.

Conclusion

The human body is powered by electricity, which is utilised in prosthetics to create bionic limbs that can move in response to electrical signals from the nervous system, or send sensory information from the limb back to the brain. This is achieved through a neural interface, where electrical signals are converted from a form that can be processed by the body to the electrochemical signals used in the nervous system.

SOURCE 1

Source type Scientific American Journal article titled ‘How artificial Arms could connect with the Nervous System’. (Ref no. 3).

Invalid source

Evaluation of source validity (CRAAP TEST) Currency: The source was published in 2013, meaning that a lot of the information surrounding technology is outdated considering recent advancements in the field. At the time that the source was written, the technology required to create mind-controlled artificial limbs hadn’t yet been fully developed, so the source writes only hypothetically. Relevance: This source is relevant to the research question. Authority: This source was published by ScientificAmerican.com, which is a magazine, not a scientific journal. The article was written by two authors: D. Kacy Cullen and Douglas H. Smith, who are both knowledgeable and authoritative in the field of neuroscience. The article was not peer reviewed. Accuracy: This source does not cite the sources of its claims, making it impossible to confirm the origins of information presented as fact. There are no clickable links or other evidence to support claims. Additionally, the information has not stood the test of time and while it may have been true in 2013, when the source was published, today it is outdated and inaccurate in regard to modern advanced technology. Purpose: There are no advertised products in this source, the information appears impartial and objective however there is a possible institutional bias as both contributing authors work for the University of Pennsylvania, although this isn’t relevant to the information in the article.

Overall, the source is too old to provide accurate up-to-date information relevant to the research question, which demands current research considering the ever-changing nature of the world of bionics. Because of this, the source was not selected for use in the presentation. For exemple, with the limited information available at the time, the source concluded that an interface with laboratory-grown nerve fibres and electricity-conducting polymers was the best way to create a connection between the nervous system and a piece of machinery, when in fact time has shown that, in fact, electrodes can be used alongside signal interpreters.

SOURCE 2

valid source

Source type Published journal article on Nature.com (trusted peer-reviewed platform for published scientific articles) titled ‘Electronic neural interfaces’ (Ref. no 4)

Evaluation of source validity (CRAAP TEST) Currency: The source was published on the 13th of April 2020. Having been published within five years, the information presented in this source is up-to-date and appropriately current. Relevance: This source is relevant to the research question as it presents the different ways that electrical connection can be made with the bodies nervous system. Authority: This source was published by nature.com, which is a well-known platform for the upload of scientific journals for peer-review. It was written by a team of knowledgeable PHD candidate authors working in the fields of biotechnology and neuroscience and was peer-reviewed. The source is authoritative as the authors and platform are trustworthy. Additionally, contact information for the lead author is provided. Accuracy: All claims made in this source are supported with evidence and clickable citations to reliable sources that can back-up contended information. The information is reliable and scientifically accurate. Purpose: There are no advertised products in this source and the information is impartial and objective. This source was produced for the sole objective of communicating research findings.

Overall, the information is current, authoritative, and accurate, making it a reliable and valid source.