The selfish meme & the selflessATMA

The word ‘meme’ was first used by Richard Dawkins (Dawkins, 1976)¹ in the sense of a replicator to introduce the idea of cultural transmission through the process of imitation, just as genes are responsible for the evolution of organisms. Following Dawkins several writers came forth to have a closer look at ‘meme’. The consensus was that this was a fascinating way of explaining cultural evolution and transmission; that meme is the basic unit of (cultural) information whose existence influences events so as to make more copies of itself (Brodie, 1996).² The book which got most attention in this line of literature wasThe Meme Machine (Blackmore, 1993),³ which favours the idea that culture, like biology, evolves through the process of variation, selection and replication. Something striking in Blackmore’s thesis is that emotions and attitudes do not count as memes since they are subjective and never get passed on.     

Odor-specific habituation arises from interaction of afferent synaptic adaptation and intrinsic synaptic potentiation in olfactory cortex

Segmentation of target odorants from background odorants is a fundamental computational requirement for the olfactory system and is thought to be behaviorally mediated by olfactory habituation memory. Data from our laboratory have shown that odor-specific adaptation in piriform neurons, mediated at least partially by synaptic adaptation between the olfactory bulb outputs and piriform cortex pyramidal cells, is highly odor specific, while that observed at the synaptic level is specific only to certain odor features. Behavioral data show that odor habituation memory at short time constants corresponding to synaptic adaptation is also highly odor specific and is blocked by the same pharmacological agents as synaptic adaptation. Using previously developed computational models of the olfactory system we show here how synaptic adaptation and potentiation interact to create the observed specificity of response adaptation. The model analyzes the mechanisms underlying the odor specificity of habituation, the dependence on functioning cholinergic modulation, and makes predictions about connectivity to and within the piriform neural network. Predictions made by the model for the role of cholinergic modulation are supported by behavioral results.Filtering sensory input is critical for information processing tasks such as background segmentation, and shifting processing power away from redundant, stable, or repetitive stimuli toward dynamic, novel stimuli. A critical aspect of this filtering however, is stimulus specificity. Under most circumstances it may be most beneficial to selectively filter the redundant stimulus, while maintaining responsiveness to different, though perhaps highly similar stimuli.In the olfactory system, short-term habituation to stable or repeated odorants involves a metabotropic glutamate receptor (mGluR)-dependent depression of afferent synapses to the piriform cortex (Best and Wilson 2004). Blockade of group III mGluR receptors prevents cortical adaptation odors (Best and Wilson 2004), and reduces short-term habituation of odor-evoked reflexes (Best et al. 2005) and odor investigation (Yadon and Wilson 2005; Bell et al. 2008; McNamara et al. 2008). This short-term habituation is highly odor specific, with minimal cross-adaptation of piriform cortical single-unit responses or cross-habituation of behavioral responses to similar odors, including between mixtures and their components (Wilson 2000; Cleland et al. 2002). Interestingly, there is an experience-dependent component to short-term habituation odor specificity. The odor specificity is most pronounced for familiar odors, with very brief (<20 sec) exposure to odors producing more generalization, and longer exposures (>50 sec) sufficient to permit strong odor specificity in cortex adaptation (Wilson 2003).The homosynaptic nature of afferent synaptic depression underlying cortical adaptation (Wilson 1998; Best and Wilson 2004) may contribute to this odor specificity. However, the experience dependence suggests that there may be an additional process involved. In fact, theoretical views of piriform cortical function suggest that the cortex learns previous patterns of input via potentiation of intracortical association fiber synapses (Hasselmo et al. 1990; Barkai et al. 1994; Haberly 2001; Linster et al. 2003). This autoassociative process essentially creates a template of previous network activity, against which new input patterns can be compared, allowing enhanced discrimination between similar patterns, as well as completion of degraded patterns (Barkai et al. 1994; Barnes et al. 2008). In support of this hypothesis, previous work has demonstrated that disruption of normal synaptic potentiation in association fiber synapses through blockade of cholinergic muscarinic receptors (Patil et al. 1998; Linster et al. 2003), reduces odor specificity of cortical adaptation (Wilson 2001b), prevents the effects of odor experience on subsequent behavioral cross-habituation (Fletcher and Wilson 2002), and disrupts odor discrimination (Linster et al. 2001).The present series of studies further explored the role of combined afferent synaptic depression and intracortical association fiber synaptic potentiation on the specificity of cortical adaptation and odor habituation. Using a computational model of the olfactory system (Linster et al. 2007), the results suggest that activity-dependent association fiber plasticity is necessary to account for the specificity of odor habituation. Furthermore, in behavioral experiments blockade of cholinergic muscarinic receptors during habituation enhances generalization of odor habituation, consistent with the modeling and with previous electrophysiological results.     

Employee Empowerment: An Integrative Psychological Approach

An integrative psychological approach to employee empowerment was developed based on the premise that the psychological experience of power underlies feelings of empowerment. This research extends existing perspectives on empowerment by incorporating the empowering effect of valued goals, such as those provided by transformational leadership. Goal internalisation was identified as a major component of the psychological experience of empowerment, in addition to the two traditional facets of perceptions of control over the work environment and perceptions of self‐efficacy or competence. Standard measure development procedures using a sample of employed individuals from Quebec, Canada and subsequent validation with an organisational sample from Ontario, Canada yielded a three‐factor scale of psychological empowerment corresponding to these three dimensions. The implications of defining empowerment as a psychological state and the need for multiple measures of empowerment are also discussed.     

Motivated cultural cognition: the impact of implicit cultural theories on dispositional attribution varies as a function of need for closure

The authors propose that need for closure (NFC) leads attributors to respond to an ambiguous social event by increasing reliance on implicit theories received from acculturation. Hence, the influence of NFC should be shaped by chronically accessible knowledge structures in a culture, and, likewise, the influence of culture should be moderated by epistemic motives such as NFC. The specific hypotheses drew on past findings that North American and Chinese attributors possess differing implicit social theories, North Americans conceiving of individuals as autonomous agents and Chinese conceiving of groups as autonomous. The present studies found the predicted pattern that among North American participants, NFC increased attributions to personal but not group dispositions. Among Chinese participants, NFC increased attributions to group but not personal dispositions. The findings are discussed in light of an emerging dynamic account of culture and cognition.     

Blazing the trail versus trailing the group: Culture and perceptions of the leader’s position

Research suggests that power triggers assertive action. However, people from different cultures might expect different types of action from powerful individuals such as leaders. In comparing cultural differences in leadership imagery, we find that Americans represent leaders standing ahead of groups, whereas Asians also represent leaders behind groups. We propose that front versus back positions embody two faces of leader action: individual assertion versus group-focused action. Studies 1a and 1b respectively employed etic and emic methods to demonstrate that Singaporeans were more likely than Americans to represent leaders behind groups. In Study 2, Singaporeans evaluated back leaders more favorably than Americans did, and group focus mediated cultural differences. Simulating the conditions under which cultural differences arise, Study 3 demonstrates that a primarily Western managerial sample primed with threat (versus opportunity) preferred back leaders. By describing cultural variations in imagery, we reveal more nuanced implicit theories of leader action.