Pic of the day: African dogs sneeze to vote

156_dog sneeze - CopyExcerpt from Walker et al. (2017), p. 5:

“We also find an interaction between total sneezes and initiator POA in rallies (table 1) indicating that the number of sneezes required to initiate a collective movement differed according to the dominance of individuals involved in the rally. Specifically, we found that the likelihood of rally success increases with the dominance of the initiator (i.e. for lower POA categories) with lower-ranking initiators requiring more sneezes in the rally for it to be successful (figure 2d). In fact, our raw data and the resultant model showed that rallies never failed when a dominant (POA1) individual initiated and there were at least three sneezes, whereas rallies initiated by lower ranking individuals required a minimum of 10 sneezes to achieve the same level of success. Together these data suggest that wild dogs use a specific vocalization (the sneeze) along with a variable quorum response mechanism in the decision-making process. […]. We found that sneezes, a previously undocumented unvoiced sound in the species, are positively correlated with the likelihood of rally success preceding group movements and may function as a voting mechanism to establish group consensus in an otherwise despotically driven social system.”

REFERENCE: Walker RH, King AJ, McNutt JW, & Jordan NR (6 Sept. 2017). Sneeze to leave: African wild dogs (Lycaon pictus) use variable quorum thresholds facilitated by sneezes in collective decisions. Proceedings of the Royal Society B. Biological Sciences, 284(1862). pii: 20170347. doi: 10.1098/rspb.2017.0347. PMID: 28878054, PMCID: PMC5597819, DOI: 10.1098/rspb.2017.0347 ARTICLE | FREE FULLTEXT PDF

By Neuronicus, 1 August 2019

Zap the brain to get more lenient judges

Reference: Buckholtz et al. (2015). Credit: Neuronicus

Humans manage to live successfully in large societies mainly because we are able to cooperate. Cooperation rests on commonly agreed rules and, equally important, the punishment bestowed upon their violators. Researchers call this norm enforcement, while the rest of us call it simply justice, whether it is delivered in its formal way (through the courts of law) or in a more personal manner (shout at the litterer, claxon the person who cut in your lane etc.). It is a complicate process to investigate, but scientists managed to break it into simpler operations: moral permissibility (what is the rule), causal responsibility (did John break the rule), moral responsibility (did John intend to break the rule, also called blameworthiness or culpability), harm assessment (how much harm resulted from John breaking the rule) and sanction (give the appropriate punishment to John). Different brain parts deal with different aspects of norm enforcement.

The approximate area where the stimulation took place. Note that the picture depicts the left hemisphere, whereas the low punishment judgement occured when the stimulation was mostly on the right hemisphere.
The approximate area where the stimulation took place. Note that the picture depicts the left hemisphere, whereas the low punishment judgement occurred when the stimulation was mostly on the right hemisphere.

Using functional magnetic resonance imaging (fMRI), Buckholtz et al. found out that the dorsolateral prefrontal cortex (DLPFC) gets activated when 60 young subjects decided what punishment fits a crime. Then, they used repetitive transcranial magnetic stimulation (rTMS), which is a non-invasive way to disrupt the activity of the neurons, to see what happens if you inhibit the DLPFC. The subjects made the same judgments when it came to assigning blame or assessing the harm done, but delivered lower punishments.

Reference: Buckholtz, J. W., Martin, J. W., Treadway, M. T., Jan, K., Zald, D.H., Jones, O., & Marois, R. (23 September 2015). From Blame to Punishment: Disrupting Prefrontal Cortex Activity Reveals Norm Enforcement Mechanisms. Neuron, 87: 1–12, http://dx.doi.org/10.1016/j.neuron.2015.08.023. Article + FREE PDF

by Neuronicus, 22 September 2015