Marmosets used in visual motion perception experiment involving brain exposure

Zavitz, E., Yu, H.H., Rowe, E.G., Rosa, M.G.P. & Price, N.S.C. (2016). Rapid Adaptation Induces Persistent Biases in Population Codes for Visual Motion. Journal of Neuroscience. 36(16) pp. 4579-4590. doi: https://doi.org/10.1523/JNEUROSCI.4563-15.2016

Associated Institution(s): Monash University and Australian Research Council Centre of Excellence for Integrative Brain Function

Background summary:


Three adult marmoset monkeys were used in a visual motion perception experiment designed to map activity in the middle temporal region of the brain.

As the brain processes and stores new visual information, it consolidates a perceptual “database”. Each new piece of visual information stored informs the processing of future visual cues, as the brain uses this database to interpret and contextualise new information. Visual changes in the environment prompt visual adaptation, where the brain incorporates new visual information into its database.

Adaptation can change how the brain encodes new information (Clifford et al., 2007). Encoding disruptions can lead to errors in perception and compromise the processing and perception of subsequent visual cues, causing perceptual biases.

This experiment aimed to study how rapid visual adaptation affects encoding, and whether these encoding changes are associated with perceptual error.            

Experimental method summary:

Visual motion is believed to be processed by neurons in the middle temporal area of the human brain.

Three adult marmoset monkeys were used in this experiment. The monkeys were anesthetized and presented with a rapid succession of visual motion (moving stimulus) cues, while the activity of 61 neurons in the middle temporal region of their brains was monitored. To prepare the monkeys for this experiment the researchers followed a modified version of the procedure developed in 2003 by Bourne and Rosa.

These procedures are carried out not only in this experiment but are used as a standard procedure in many experiments where animals are restrained for brain research.

The monkeys are subjected to the following experimental stages:

  1. The monkeys are anesthetized.
  2. A tracheotomy is performed which involves an incision in the windpipe through which a breathing tube is inserted and artificial ventilation occurs.
  3. Cannulation of the femoral vein in the thigh is performed.
  4. A solution of opiate anesthetic (sufentanil) and paralytic (pancuronium bromide) is administered intravenously.
  5. Atropine and phenylephrine hydrochloride eye drops are administered, the cornea is protected, and contact lenses are fitted to the eyes.
  6. A craniotomy (surgical removal of part of the skull to expose the brain) is performed
  7. A durotomy incision is performed over the middle temporal brain region, and an electrode system is implanted into the brain to record brain activity during the experiment.
  8. Visual motion stimuli are presented (white dots on a black background). Dots moved coherently with no noise.
  9. Whilst the monkeys are anesthetized, chemically paralysed and artificially ventilated the researchers record their brain activity.

Following completion of the experiment, the monkeys were euthanised and further neurological research was conducted on their brains post-mortem.

Relevance to Humans:

While live non-human animal use continues to routinely occur in neuroscientific and broader biomedical research, concerns remain about the relevance and ethics of these practices and their outcomes. While there are similarities between visual processing systems in the brains of humans and non-human primates, differences are also reported (Matsuno & Fujita, 2009).

There are key anatomical differences between animals - including marmosets - and humans (Pound et al., 2004). The inefficiency and high financial costs associated with research on in-vivo (living) animal models has also been acknowledged as a limitation of in-vivo research designs that use non-human animals (Sprankle, 2016).

In the United States of America, innovative and highly efficient computational models have been developed for toxicology testing. These alternative models aggregate data from multiple existing studies, producing complex computational testing models superior to in-vivo animal models (Sprankle, 2016). Many studies and systematic reviews show that there is discordance between animal and human studies, and that non-human animal research subjects fail to adequately mimic human clinical biological patterns or responses (Perel et al., 2007; Van der Worp et al., 2010).

The above information indicates the outdatedness of in-vivo animal models and the need to embrace innovative research approaches such as computational research models. Embracing technologically sophisticated, efficient and ethically progressive research approaches in scientific research is likely to yield research data of increased relevance to human neurology.

Funding:

This work was funded by National Health and Medical Research Council Project Grants APP1008287 ($495,674)  and APP1066588 ($338,524), Human Frontier Science Program Career Development Award to N.S.C.P., the ARC SRI in Bionic Vision, and the ARC Centre of Excellence for Integrative Brain Function. Sufentanil citrate was donated by Janssen-Cilag Pty Limited.

References

Asher, A. (2016). Dural sac tears. Retrieved from: https://www.verywell.com/cerebrospinal-fluid-leak-and-dural-tears-296512

Bourne, JA & Rosa, MGP 2003, 'Preparation for the in vivo recording of neuronal responses in the visual cortex of anaesthetised marmosets (Callithrix jacchus)', Brain Research Protocols, 11: 168–177.

Clifford, C.W.G., Webster, M.A., Stanley, G.B., Stocker, A.A., Kohn, A., Sharpee, T.O., & Schwartz, O. (2007). Visual adaptation: Neural, psychological and computational aspects. Vision Research. 47. Pp. 3125-3131. doi:10.1016/j.visres.2007.08.023

Matsuno, T. & Fujita, K. (2009). A comparative psychophysical approach to visual perception in primates. Primates. 50(2). pp. 121-130. doi:10.1007/s10329-008-0128-8

Pound P., Ebrahim S., Sandercock P., Bracken M.B., Roberts I.; on behalf of the Reviewing Animal Trials Systematically Group. 2004. ‘Where is the evidence that animal research benefits humans?’, BMJ, 328, 514-7.

Perel P, Roberts I, Sena E, Wheble P, Briscoe C, Sandercock P, Macleod, M., Mignini, L.E., Jayaram, P., Khan, K.S. (2007). Comparison of treatment effects between animal experiments and clinical trials: systemic review, British Medical Journal, 334(7586), pp.197-200. doi: 10.1136/bmj.39048.407928.BE

Sprankle, C. (2016). Kleinstreuer highlights groundbreaking approaches to safety testing. Retrieved from: https://www.niehs.nih.gov/news/newsletter/2016/6/community-impact/kleinstreuer/index.htm

Van der Worp, H., Howells, D.V., Sena, E.S., Porritt, M.J., Rewell, S., O’Collins, V.,  Macleod, M.R. (2010). Can animal models of disease reliably inform human studies?, PLoS Medicine. 7(3).  doi: 10.1371/journal.pmed.1000245

Case Studies Categories

© 2016 Humane Research Australia (ABN 17 208 630 818)  Terms & Conditions