Pavlov's Cockroach: Classical Conditioning of Salivation in an Insect

Secretion of saliva to aid swallowing and digestion is an important physiological function found in many vertebrates and invertebrates. Pavlov reported classical conditioning of salivation in dogs a century ago. Conditioning of salivation, however, has been so far reported only in dogs and humans, and its underlying neural mechanisms remain elusive because of the complexity of the mammalian brain. We previously reported that, in cockroaches Periplaneta americana, salivary neurons that control salivation exhibited increased responses to an odor after conditioning trials in which the odor was paired with sucrose solution. However, no direct evidence of conditioning of salivation was obtained. In this study, we investigated the effects of conditioning trials on the level of salivation. Untrained cockroaches exhibited salivary responses to sucrose solution applied to the mouth but not to peppermint or vanilla odor applied to an antenna. After differential conditioning trials in which an odor was paired with sucrose solution and another odor was presented without pairing with sucrose solution, sucrose-associated odor induced an increase in the level of salivation, but the odor presented alone did not. The conditioning effect lasted for one day after conditioning trials. This study demonstrates, for the first time, classical conditioning of salivation in species other than dogs and humans, thereby providing the first evidence of sophisticated neural control of autonomic function in insects. The results provide a useful model system for studying cellular basis of conditioning of salivation in the simpler nervous system of insects

Relative deprivation and inequalities in social and political activism

In this paper we analyse whether relative deprivation has divergent effects on different types of social and political action. We expect that it will depress volunteering with parties as well as different types of conventional political participation more generally while stimulating volunteering with anti-cuts organisations and engagement in various kinds of protest activism. There is little research into how relative deprivation impacts on different types of social and political action from the wide range of activities available to citizens in contemporary democracies as well as into how this relationship might vary based on the wider economic context. While many studies construct scales, we examine participation in specific activities and associations, such as parties or anti-cuts organisations, voting, contacting, demonstrating and striking to show that deprivation has divergent effects that depart from what is traditionally argued. We apply random effects models with cross-level interactions utilizing an original cross-national European dataset collected in 2015 (N = 17,667) within a collaborative funded-project. We show that a negative economic context has a mobilizing effect by both increasing the stimulating effect of relative deprivation on protest activism as well as by closing or reversing the gap between resource-poor and resource-rich groups for volunteering with parties and voting

Predicting support for social action: how values, justice-related variables, discrete emotions, and outcome expectations influence support for the Stolen Generations

The Stolen Generations are Indigenous Australians who were taken from their homes by the State and placed in children’s homes or foster care. This study investigated relations between the values held by Non-Indigenous Australians and willingness to support a hypothetical organization set up to repair the damage caused. Participants (N = 235) completed the Schwartz Portrait Values Questionnaire followed by items concerning their perceived responsibility; Indigenous deservingness; feelings of pleasure, anger, guilt, regret, shame, and sympathy; their support for the organization; and how efficacious they expected their support would be. It was found at the bivariate level that support was positively associated with self-transcendence values (universalism, benevolence) and negatively associated with both self-enhancement (power, achievement, hedonism) and security values. A path analysis implied that universalism values influenced support via the justice-related variables of perceived responsibility and undeserved treatment, outcome expectations, negative emotions, and sympathy. This study contributes new information about the effects of values on personal willingness to repair past wrongs.N. T. Feather, Lydia Woodyatt, Ian R. McKe