Department of Life Sciences and Biotechnology, University of Ferrara, Via Borsari 46, 44121, Ferrara, Italy.
Department of General Psychology, University of Padova, Padova, Italy.
Anim Cogn. 2020 May;23(3):535-543. doi: 10.1007/s10071-020-01357-4. Epub 2020 Feb 7.
In humans, individual and sex differences have been long reported for several cognitive tasks and are at least in part due to variability in the function that inhibits behaviour (i.e. inhibitory control). Similar evidence of individual and sex differences in inhibitory abilities is also present in other vertebrates, but is scarce outside primates. Experiments on reversal learning, which requires inhibiting behaviours, suggest that this variability may exist in a teleost fish, the guppy, Poecilia reticulata. We tested this hypothesis by observing guppies in an inhibitory task. Guppies were exposed to unreachable prey inside a transparent tube for six trials. Guppies showed a marked reduction in the number of attempts to catch the prey within the first trial and also over repeated trials. We found a striking sex difference in the capacity to inhibit foraging behaviour. Males attempted to attack the prey twice as often as females and showed negligible improvement over trials. Irrespective of sex, individuals remarkably differed in their performance, with some guppies being systematically more skilled than others across the repeated trials. These results confirm that individual and sex differences in the ability to inhibit behaviour are not restricted to humans and other primates, suggesting that they might be widespread among vertebrates. Variability in inhibitory ability provides an explanation for emerging records of variability in other cognitive tasks in fish.
在人类中，已经有很长一段时间报道了个体和性别差异在几个认知任务中存在，并且至少部分归因于抑制行为的功能（即抑制控制）的变异性。在其他脊椎动物中，也存在类似的抑制能力个体和性别差异的证据，但在灵长类动物之外则很少见。关于需要抑制行为的反转学习的实验表明，这种可变性可能存在于一种硬骨鱼，即孔雀鱼，Poecilia reticulata 中。我们通过在抑制任务中观察孔雀鱼来检验这一假设。孔雀鱼在一个透明的管子内接触不到的猎物前进行了六次试验。在第一次试验中，孔雀鱼明显减少了捕捉猎物的次数，而且在反复试验中也是如此。我们发现，在抑制觅食行为的能力方面存在显著的性别差异。雄性攻击猎物的次数是雌性的两倍，而且在试验中几乎没有改善。无论性别如何，个体在表现上差异显著，一些孔雀鱼在整个重复试验中明显比其他个体更熟练。这些结果证实，个体和性别差异在抑制行为的能力方面不仅限于人类和其他灵长类动物，表明它们可能在脊椎动物中广泛存在。抑制能力的可变性为鱼类其他认知任务的可变性的新记录提供了一种解释。
