Vulnerability Across the Life Course

This issue defines vulnerability as a key interdisciplinary concept for understanding life trajectories. Moreover, it develops a life course framework to study vulnerability along three structuring axes of research: multidimensionality, multilevel, and multidirectionality.     

Improving left spatial neglect through music scale playing

The study assessed whether the auditory reference provided by a music scale could improve spatial exploration of a standard musical instrument keyboard in right‐brain‐damaged patients with left spatial neglect. As performing music scales involves the production of predictable successive pitches, the expectation of the subsequent note may facilitate patients to explore a larger extension of space in the left affected side, during the production of music scales from right to left. Eleven right‐brain‐damaged stroke patients with left spatial neglect, 12 patients without neglect, and 12 age‐matched healthy participants played descending scales on a music keyboard. In a counterbalanced design, the participants' exploratory performance was assessed while producing scales in three feedback conditions: With congruent sound, no‐sound, or random sound feedback provided by the keyboard. The number of keys played and the timing of key press were recorded. Spatial exploration by patients with left neglect was superior with congruent sound feedback, compared to both Silence and Random sound conditions. Both the congruent and incongruent sound conditions were associated with a greater deceleration in all groups. The frame provided by the music scale improves exploration of the left side of space, contralateral to the right hemisphere, damaged in patients with left neglect. Performing a scale with congruent sounds may trigger at some extent preserved auditory and spatial multisensory representations of successive sounds, thus influencing the time course of space scanning, and ultimately resulting in a more extensive spatial exploration. These findings offer new perspectives also for the rehabilitation of the disorder.     

Post-retrieval disruption of a cocaine conditioned place preference by systemic and intrabasolateral amygdala β2- and α1-adrenergic antagonists

Previous work has demonstrated post-retrieval impairment in associative learning paradigms, including those mediated by drugs of abuse, using nonspecific β-adrenergic receptor (β-AR) antagonists. Remarkably little is known about the role of the specific β-AR subtypes, or other adrenergic receptors, in these effects. The current study examined the effects of β₁ and β₂, as well as α₁-adrenergic receptor antagonism following retrieval of a cocaine conditioned place preference (CPP). We found that rats administered the β₂ antagonist ICI 118,551 (8 mg/kg intraperitoneal [IP]) or the α₁ antagonist prazosin (1 mg/kg IP) following a drug-free test for CPP showed attenuated preference during a subsequent test, while the β₁ antagonist betaxolol (5 or 10 mg/kg IP) and a lower dose of prazosin (0.3 mg/kg IP) had no effect. Furthermore, post-test microinfusion of ICI 118,551 (6 nmol/side) or prazosin (0.5 nmol/side) into the basolateral amygdala (BLA) also impaired a subsequent preference. Systemic or intra-BLA ICI 118,551 or prazosin administered to rats in their home cages, in the absence of a preference test, had no effect on CPP 24 h later. ICI 118,551 also attenuated the FOS response in the BLA induced by the CPP test. These results are the first to demonstrate a role for α₁- and β₂-specific adrenergic mechanisms in post-retrieval memory processes. These systemic and site-specific injections, as well as the FOS immunohistochemical analyses, implicate the importance of specific noradrenergic signaling mechanisms within the BLA in post-retrieval plasticity.Substantial evidence indicates that information acquired during a learning event is initially plastic, at which time memory retention can be disrupted, but is strengthened by a time-dependent consolidation process (McGaugh 2000). Recent work has focused on retrieval-induced plasticity, a process by which changes in the retention of previously acquired information are possible. The notion of reconsolidation, one theoretical mechanism by which such changes may occur, suggests that a retrieved memory enters a labile state and is vulnerable to disruption (Sara 2000; Nader 2003). Although the theoretical mechanisms underlying reconsolidation remain unclear, the behavioral effects have been demonstrated across many different learning paradigms using a variety of pharmacological manipulations (for review, see Tronson and Taylor 2007; Diergaarde et al. 2008). Studies with aversive and appetitive preparations, including drug reward-mediated learning, have demonstrated that the noradrenergic system is important for these post-retrieval memory processes (Przybyslawski et al. 1999; Debiec and Ledoux 2004; Bernardi et al. 2006; Diergaarde et al. 2006; Robinson and Franklin 2007; Abrari et al. 2008; Fricks-Gleason and Marshall 2008; Milton et al. 2008). For example, using an animal model of cocaine-conditioned behaviors, Bernardi et al. (2006) demonstrated that systemic post-retrieval administration of propranolol impaired a subsequent conditioned place preference (CPP), suggesting that β-adrenergic receptors (β-ARs) play an important role in processes occurring following drug memory retrieval.However, most of what is known about the noradrenergic system in the memory processes that follow cued reminder trials comes from studies that use nonspecific β-AR antagonists, such as propranolol. As a consequence, several issues regarding ARs and post-retrieval memory processes remain unresolved. First, because propranolol has affinity for both β₁- and β₂-AR subtypes, it is unclear which subtype mediates these effects. To date, no studies have examined reconsolidation-like impairments using subtype-specific β-AR antagonists, which is important because more specific medications may be equally efficacious with less adverse effects. Second, no studies to date have examined α-ARs regarding a potential role in reconsolidation-like effects. α-ARs—specifically α₁-ARs—have a demonstrated role in memory consolidation (Ferry et al. 1999a,b) and may also mediate post-retrieval processes. Third, although the BLA has had a demonstrated role in reconsolidation-like effects in numerous studies, the behavioral conditions during retrieval of drug-associated memories leading to gene expression within the basolateral amygdala (BLA) have not clearly been defined. Specifically, in the CPP paradigm used here, it is unclear whether exposure to a cocaine cue alone will induce gene expression or whether a preference for the drug-associated environment needs to be expressed for BLA involvement (Franklin and Druhan 2000; Miller and Marshall 2005).Understanding the role of specific adrenergic receptors in mediating post-retrieval memory processes is particularly important in drug-induced CPP. In humans, drug-associated stimuli can facilitate drug use (Gawin 1991; See 2005) or precipitate relapse following abstinence (O''Brien et al. 1992). Thus, pharmacotherapies targeting these memory processes would benefit from a clearer understanding of the specific receptors that mediate behavioral effects (Taylor et al. 2009).Here, we first examined the effects of systemic post-test β₁-, β₂-, and α₁-AR antagonism on cocaine CPP. We then focused on the BLA due to its involvement in reconsolidation-like effects in drug learning paradigms (e.g., Lee et al. 2005), employing microinfusions of AR antagonists and measuring FOS immunoreactivity (FOS-IR) to examine the BLA as a potential site of AR-mediated impairments.     

Does Education Influence Ethical Decisions? An International Study

This study examined whether having attended a public, private or religious affiliated grade and/or high school influenced a college student’s ethical decision making process. We also examined whether having taken an ethics course in college influences a student’s ethical decision making process. Our sample included 508 accounting students (237 men and 271 women) from Albania, Ecuador, Ireland and the United States. Our analyses indicated no differences in ethical decision making that associated with either grade-or-high-school education. While our data showed no difference in the reported attitudes between students from Ecuador and the United States after controlling for social desirability response bias, we found significant differences between the attitudes students from the United States and students from both Albania and Ireland. While gender was also significant for six of our seven scenarios, social desirability response bias was significant in all of our scenarios.