Developmental history and stress responsiveness are related to response inhibition, but not judgement bias, in a cohort of European starlings (Sturnus vulgaris)

Abstract

Judgement bias tasks are designed to provide markers of affective states. A recent study of European starlings (Sturnus vulgaris) demonstrated modest familial effects on judgement bias performance, and found that adverse early experience and developmental telomere attrition (an integrative marker of biological age) both affected judgement bias. Other research has shown that corticosterone levels affect judgement bias. Here, we investigated judgement bias using a modified Go/No Go task in a new cohort of starlings (n = 31) hand-reared under different early-life conditions. We also measured baseline corticosterone and the corticosterone response to acute stress in the same individuals. We found evidence for familial effects on judgement bias, of a similar magnitude to the previous study. We found no evidence that developmental treatments or developmental telomere attrition were related to judgement bias per se. We did, however, find that birds that experienced the most benign developmental conditions, and birds with the greatest developmental telomere attrition, were significantly faster to probe the learned unrewarded stimulus. We also found that the birds whose corticosterone levels were faster to return towards baseline after an acute stressor were slower to probe the learned unrewarded stimulus. Our results illustrate the potential complexities of relationships between early-life experience, stress and affectively mediated decision making. For judgement bias tasks, they demonstrate the importance of clearly distinguishing factors that affect patterns of responding to the learned stimuli (i.e. response inhibition in the case of the Go/No Go design) from factors that influence judgements under ambiguity.Electronic supplementary materialThe online version of this article (10.1007/s10071-018-1226-7) contains supplementary material, which is available to authorized users.

A consideration of the role of biology and test design as confounding factors in judgement bias tests

“…In the study by Bateson et al, 2015 this proposition was supported with starlings that had come from bigger broods, with larger nest competitors, indicating pessimistic responses in a go/no go task. A later starling study, albeit with a slightly modified protocol, found opposing results such that birds reared under the least stress were faster in probe response (Gott et al, 2019).…”

Short telomeres drive pessimistic judgement bias in zebrafish

“…Therefore, judgement bias has been seen mainly as a phenotypic state influenced by the current affective state of the individual, which depends to a great extent on the environment to which the individual is exposed, rather than a constitutive phenotypic trait, while research on the genetic component of judgement bias is scarce (e.g. [9,10]). In this respect, the availability of mutant lines for the telomerase reverse transcriptase (TERT) [11], which is the core catalytic protein component of telomerase, opens the possibility of testing the hypothesis that pessimism may be causally driven by telomere attrition (i.e.…”

Individual behavioural differences in social species a multidisciplinary study with mice and ants

“…The judgement bias experimental paradigm formed the basis for most subsequent studies in the field (Mendl et al 2009). Based on this proposition, judgement biases have been measured in a range of different laboratory animals (mice; genus Mus, as reviewed by Mendl et al, 2009, rats, genus Rattus, Barker et al, 2016, Brydges & Hall, 2017 Gott et al, 2019 andbottlenose dolphins, Tursiops truncatus, Clegg et al, 2017). By presenting a simplified approach that allows to widely explore several cognitive bias measures, and interpretations about the affective states of individuals, the judgement bias test became one of the most reliable methods to study animal welfare (see also Bethell et al, 2012;Burman et al, 2008).…”