Random attention can explain apparent object choice behavior in free-walking blowflies

Flies are often observed to approach dark objects. To a naive observer they seem to pay selective attention to one out of several objects although previous research identified a reflex-like fixation behavior integrating responses to all objects as possible underlying mechanism. In a combination of behavioral experiments and computational modelling, we investigate the choice behavior of flies freely walking towards an arrangement of two objects placed at a variable distance from each other. The walking trajectories are oriented towards one of the objects much earlier than predicted by a simple reactive model. We show that object choice can be explained by a continuous control scheme in combination with a mechanism randomly responding to the position of each object according to a stochastic process. Although this may be viewed as a special form of an attention-like mechanism, the model does not require an explicit decision mechanism or a memory for the drawn decision.

Dopaminergic signaling supports auditory social learning

Explicit rewards are commonly used to reinforce a behavior, a form of learning that engages the dopaminergic neuromodulatory system. In contrast, skill acquisition can display dramatic improvements from a social learning experience, even though the observer receives no explicit reward. Here, we test whether a dopaminergic signal contributes to social learning in naïve gerbils that are exposed to, and learn from, a skilled demonstrator performing an auditory discrimination task. Following five exposure sessions, naïve observer gerbils were allowed to practice the auditory task and their performance was assessed across days. We first tested the effect of an explicit food reward in the observer’s compartment that was yoked to the demonstrator’s performance during exposure sessions. Naïve observer gerbils with the yoked reward learned the discrimination task significantly faster, as compared to unrewarded observers. The effect of this explicit reward was abolished by administration of a D1/D5 dopamine receptor antagonist during the exposure sessions. Similarly, the D1/D5 antagonist reduced the rate of learning in unrewarded observers. To test whether a dopaminergic signal was sufficient to enhance social learning, we administered a D1/D5 receptor agonist during the exposure sessions in which no reward was present and found that the rate of learning occurred significantly faster. Finally, a quantitative analysis of vocalizations during the exposure sessions suggests one behavioral strategy that contributes to social learning. Together, these results are consistent with a dopamine-dependent reward signal during social learning.

Relaying Aversive USVs Alarm Calls Depends on the Previous Experience. Empathy, Social Buffering or Panic?

Ultrasonic vocalizations (USVs) are one of the evolutionarily oldest forms of animal communication. In order to study the communication architecture in an aversive social situation, we used a behavioral model in which one animal, the observer, is witnessing as his cagemate, the demonstrator, is experiencing a series of mild electrical foot-shocks (aversive stimuli). We studied the effect of foot-shocks experience in the observer and the influence of a warning sound (emit-ted shortly before the shock is applied) on USVs communication. These experiments revealed that such a warning seems to increase the arousal level, which differentiates the responses depending on previous experience. It can be identified by the emission of characteristic, short 22-kHz calls, of a duration below 100 ms. Furthermore, by analyzing temporally overlapping USVs, we found that in ‘Warned’ pairs with a naive observer, 22-kHz were mixed with 50-kHz calls. This fact, combined with a high fraction of very high-pitched 50-kHz calls (over 75-kHz), suggests the presence of the phenomenon of social buffering. On the other hand, in ‘Warned’ pairs with an experienced observer, pure 22-kHz overlaps were mostly found, signifying possible fear contagion with dis-tress sharing. Hence the importance of differentiating 22-kHz calls to long and short.

Dopaminergic signaling supports auditory social learning

Explicit rewards are commonly used to reinforce a behavior, a form of learning that engages the dopaminergic neuromodulatory system. In contrast, skill acquisition can display dramatic improvements from a social learning experience, even though the observer receives no explicit reward. Here, we test whether a dopaminergic signal contributes to social learning in naïve gerbils that are exposed to, and learn from, a skilled demonstrator performing an auditory discrimination task. Following five exposure sessions, naïve observer gerbils were allowed to practice the auditory task, and their performance was assessed across days. We first tested the effect of an explicit food reward in the observer’s compartment that was yoked to the demonstrator’s performance during exposure sessions. Naïve observer gerbils with the yoked reward learned the discrimination task significantly faster, as compared to unrewarded observers. The effect of this explicit reward was abolished by administration of a D1/D5 dopamine receptor antagonist during the exposure sessions. Similarly, the D1/D5 antagonist reduced the rate of learning in unrewarded observers. To test whether a dopaminergic signal was sufficient to enhance social learning, we administered a D1/D5 receptor agonist during the exposure sessions in which no reward was present, and found that the rate of learning occurred significantly faster. Finally, a quantitative analysis of observer vocalizations and movements during the exposure sessions suggest behavioral strategies that contribute to social learning. Together, these results are consistent with a dopamine-dependent reward signal during social learning.

Effect of demonstrator reliability and recency of last demonstration on acquisition of a socially transmitted food preference

In the social transmission of food preference paradigm, naive observer rats acquire safety information about novel food sources in the environment through social interaction with a demonstrator rat that has recently eaten said food. Research into the behavioural mechanisms governing this form of learning has found that observers show increased reliance on socially acquired information when the state of the environment makes personal examination of their surroundings risky. We aimed to (1) determine whether reliance on social information would decrease if previous reliance on social learning was unsuccessful, and (2) whether reliance on the specific demonstrator that had transmitted poor information would similarly decrease. By inducing illness in observers following consumption of a socially demonstrated food, we created an environmental situation in which reliance on socially acquired information was maladaptive. We found that under these conditions, observers showed no change in their reliance on a specific demonstrator or socially learned information in general. Our experiment also unexpectedly produced results showing that recent demonstrators were more influential in later transmissions than demonstrators that had been learned from less recently. Notably, this effect only emerged when the observer simultaneously interacted with both demonstrators, indicating that demonstrators must be in direct competition for this effect to manifest.

What Reveals the Taste of the City: The Ethics of Urbanity

Urbanity, a notion that originates in the discourses on rhetoric, designates an ethics proper to the city: a witty, distanced behaviour that replaces the authentic person by the playful enactment of a role. This involves - as every theatre - the presence of an illusion; a certain ‘as if’; a deception, yet one that does not deceive anybody. The belief in the illusion becomes interpassively delegated to a kind of virtual, naive observer. Postmodernity, with its obsession with questions of true identity, can be seen as the key enemy of this urban role-play. It thus contributes to the neoliberal privatization and destruction of urban, public space.

Children’s ability to attribute different interpretations of ambiguous drawings to a naive vs. a biased observer

In two experiments we investigated 5- to 7-year-olds’ ability to attribute to a naive or a biased observer an interpretation of ambiguous drawings (restricted views of a nondescript part of a depicted object) corresponding to that observer’s mental state: ignorance for the naive observer and expectation for the biased observer. In Experiment 1, in which the expectation was only based on the observer’s prior viewing experience, children mostly failed to infer a proper interpretation for both a biased and a naive observer; instead, they ascribed to this character an interpretation corresponding to the real identity of the target picture. In Experiment 2, in which the expectation was additionally based on a more stable characteristic of the observer, a high percentage of children succeeded in generating for the biased observer an interpretation according to that expectation. For the naive observer, children’s answers seemed to be at random. In addition, we used a replication of Gopnik and Astington’s “book” task (1988), obtaining different results. We conclude that children aged 5 to 7 years have a rudimentary understanding of the interpretive nature of external representations. Hence their varying performance on interpretive theory of mind tasks, depending on the details of the task or the context in which it is presented.