Reagan Beck - Academia.edu (original) (raw)
Papers by Reagan Beck
In several species, including humans, the dentate granule cell layer (GCL) of the hippocampus exh... more In several species, including humans, the dentate granule cell layer (GCL) of the hippocampus exhibits neurogenesis throughout adult life. The ability to regulate adult neurogenesis pharmacologically may be of therapeutic value as a mechanism for replacing lost neurons. Insulin-like growth factor-I (IGF-I) is a growth-promoting peptide hormone that has been shown to have neurotrophic properties. The relationship between IGF-I and adult hippocampal neurogenesis is to date unknown. The aim of this study was to investigate the effect of the peripheral administration of IGF-I on cellular proliferation in the dentate subgranular proliferative zone, which contains neuronal progenitor cells, and on the subsequent migration and differentiation of progenitor cells within the GCL. Using bromodeoxyuridine (BrdU) labeling, we found a significant increase of BrdUimmunoreactive progenitors in the GCL after 6 d of peripheral IGF-I administration. To determine the cell fate in progenitor progeny, we characterized the colocalization of BrdUimmunolabeled cells with cell-specific markers. In animals treated with IGF-I for 20 d, BrdU-positive cells increased significantly. Furthermore, the fraction of newly generated neurons in the GCL increased, as evaluated by the neuronal markers Calbindin D 28K , microtubule-associated protein-2, and NeuN. There was no difference in the fraction of newly generated astrocytes. Thus, our results show that peripheral infusion of IGF-I increases progenitor cell proliferation and selectively induces neurogenesis in the progeny of adult neural progenitor cells. This corresponds to a 78 Ϯ 17% ( p Ͻ 0.001) increase in the number of new neurons in IGF-I-treated animals compared with controls.
Psychopharmacology, 2009
Rationale Attentional and sensorimotor gating deficits in human depression are observed as residu... more Rationale Attentional and sensorimotor gating deficits in human depression are observed as residual symptoms irrespective of antidepressant treatment. Clinical studies point to a benefit of modafinil in depression. No data are available on modafinil effects in depression-like animal models. Objectives We investigated effects of modafinil on attention and sensorimotor gating after subchronic treatment during a restraint stress protocol inducing depression-like changes in rats. Materials and methods Effects of modafinil were investigated (a) acutely in the forced swim test (FST) 1 h after administration of drug or placebo and (b) in a further experiment on cognition-related behaviour in rats after induction of depression-like changes using a restraint stress protocol for 15 days. Beginning from day 10, one restrained (R) and one non-restrained (NR) group were treated with modafinil (R-M and NR-M groups) and two groups with placebo (R-P and NR-P groups). At the end of protocol, behavioural testing was performed under conditions of nearly drug-free plasma. Depression-like behaviour was examined in the FST. Selective attention and sensorimotor gating were investigated as social novelty discrimination (SND) and prepulse inhibition (PPI) of acoustic startle response. Results Restraint led to reduced body weight, decreased mobility in the FST and impaired cognitive capabilities in the SND and the PPI. Subchronic modafinil treatment reversed restraint-induced deficits in the FST, the SND and PPI, whereas it was without effect on body weight. Conclusions The improvement of impaired attentional and information-processing functions under depression-like conditions suggests a benefit of modafinil in treatment of cognitive residual symptoms in affective disorders.
Language and Intercultural Communication, 2010
Despite their diverse national backgrounds, 28 interviewees speak similarly about the complexity ... more Despite their diverse national backgrounds, 28 interviewees speak similarly about the complexity of the cultural realities with which they live, and refuse to be pinned down to specific cultural types. While nation is of great importance, unless personally inspiring, it tends to be an ...
All children should have scheduled visits to various healthcare providers. The American Academy o... more All children should have scheduled visits to various healthcare providers. The American Academy of Pediatrics recommends 12 scheduled well-child care visits between 3–5 days of age and age 3, and yearly visits thereafter (Mozingo, 2009). General developmental surveillance should occur during these visits, as well as developmental screening, when indicated. The American Academy of Pediatrics (2010) also recommended an immunization schedule for children of age 0 through 6 years. The 2010 schedule includes 25 shots during the first 15 months of life that generally are given during the well care visits.
Effective collaboration dynamics are at the core of learning, knowledge exchange and innovation p... more Effective collaboration dynamics are at the core of learning, knowledge exchange and innovation processes. Nevertheless, in today's global environment, a large number of collaboration initiatives fail to deliver the value expected, as complexity is increased by the diversity and the distributed nature of the people, groups, and knowledge sources and by the knowledge integration processes involved. Effective collaboration competencies are hence emerging as a key condition for productive and sustainable value creation at the individual, team, organizational and inter-organizational level. L2C -Learning to Collaborate -is an ongoing research project addressing the design of effective immersive simulation-based learning experiences supporting the development of collaboration competencies both at the individual and organizational level. The key characteristic of such advanced learning tools consists in the integration of psychological, motivational, cognitive, organizational, cultural and technological factors affecting the success or failure of collaboration into the modeling of a set of virtual characters with whom learners can interact dynamically within a challenging and realistic collaboration scenario. This paper provides an overview of the conceptual basis, key design principle s and expected pedagogical impact of this new type of immersive simulation-based learning experience.
Disability & Society, 2009
... View all references; Priestley 200129. Priestley, M. 2001. ... It focuses on their behaviour ... more ... View all references; Priestley 200129. Priestley, M. 2001. ... It focuses on their behaviour rather than on the structure of society and its inequalities (Burton and Kagan 20066. Burton, M. and Kagan, C. 2006. Decoding Valuing people . Disability & Society , 21(4): 299313. ...
Quarterly Journal of Experimental Psychology, 2009
In several species, including humans, the dentate granule cell layer (GCL) of the hippocampus exh... more In several species, including humans, the dentate granule cell layer (GCL) of the hippocampus exhibits neurogenesis throughout adult life. The ability to regulate adult neurogenesis pharmacologically may be of therapeutic value as a mechanism for replacing lost neurons. Insulin-like growth factor-I (IGF-I) is a growth-promoting peptide hormone that has been shown to have neurotrophic properties. The relationship between IGF-I and adult hippocampal neurogenesis is to date unknown. The aim of this study was to investigate the effect of the peripheral administration of IGF-I on cellular proliferation in the dentate subgranular proliferative zone, which contains neuronal progenitor cells, and on the subsequent migration and differentiation of progenitor cells within the GCL. Using bromodeoxyuridine (BrdU) labeling, we found a significant increase of BrdUimmunoreactive progenitors in the GCL after 6 d of peripheral IGF-I administration. To determine the cell fate in progenitor progeny, we characterized the colocalization of BrdUimmunolabeled cells with cell-specific markers. In animals treated with IGF-I for 20 d, BrdU-positive cells increased significantly. Furthermore, the fraction of newly generated neurons in the GCL increased, as evaluated by the neuronal markers Calbindin D 28K , microtubule-associated protein-2, and NeuN. There was no difference in the fraction of newly generated astrocytes. Thus, our results show that peripheral infusion of IGF-I increases progenitor cell proliferation and selectively induces neurogenesis in the progeny of adult neural progenitor cells. This corresponds to a 78 Ϯ 17% ( p Ͻ 0.001) increase in the number of new neurons in IGF-I-treated animals compared with controls.
Psychopharmacology, 2009
Rationale Attentional and sensorimotor gating deficits in human depression are observed as residu... more Rationale Attentional and sensorimotor gating deficits in human depression are observed as residual symptoms irrespective of antidepressant treatment. Clinical studies point to a benefit of modafinil in depression. No data are available on modafinil effects in depression-like animal models. Objectives We investigated effects of modafinil on attention and sensorimotor gating after subchronic treatment during a restraint stress protocol inducing depression-like changes in rats. Materials and methods Effects of modafinil were investigated (a) acutely in the forced swim test (FST) 1 h after administration of drug or placebo and (b) in a further experiment on cognition-related behaviour in rats after induction of depression-like changes using a restraint stress protocol for 15 days. Beginning from day 10, one restrained (R) and one non-restrained (NR) group were treated with modafinil (R-M and NR-M groups) and two groups with placebo (R-P and NR-P groups). At the end of protocol, behavioural testing was performed under conditions of nearly drug-free plasma. Depression-like behaviour was examined in the FST. Selective attention and sensorimotor gating were investigated as social novelty discrimination (SND) and prepulse inhibition (PPI) of acoustic startle response. Results Restraint led to reduced body weight, decreased mobility in the FST and impaired cognitive capabilities in the SND and the PPI. Subchronic modafinil treatment reversed restraint-induced deficits in the FST, the SND and PPI, whereas it was without effect on body weight. Conclusions The improvement of impaired attentional and information-processing functions under depression-like conditions suggests a benefit of modafinil in treatment of cognitive residual symptoms in affective disorders.
Language and Intercultural Communication, 2010
Despite their diverse national backgrounds, 28 interviewees speak similarly about the complexity ... more Despite their diverse national backgrounds, 28 interviewees speak similarly about the complexity of the cultural realities with which they live, and refuse to be pinned down to specific cultural types. While nation is of great importance, unless personally inspiring, it tends to be an ...
All children should have scheduled visits to various healthcare providers. The American Academy o... more All children should have scheduled visits to various healthcare providers. The American Academy of Pediatrics recommends 12 scheduled well-child care visits between 3–5 days of age and age 3, and yearly visits thereafter (Mozingo, 2009). General developmental surveillance should occur during these visits, as well as developmental screening, when indicated. The American Academy of Pediatrics (2010) also recommended an immunization schedule for children of age 0 through 6 years. The 2010 schedule includes 25 shots during the first 15 months of life that generally are given during the well care visits.
Effective collaboration dynamics are at the core of learning, knowledge exchange and innovation p... more Effective collaboration dynamics are at the core of learning, knowledge exchange and innovation processes. Nevertheless, in today's global environment, a large number of collaboration initiatives fail to deliver the value expected, as complexity is increased by the diversity and the distributed nature of the people, groups, and knowledge sources and by the knowledge integration processes involved. Effective collaboration competencies are hence emerging as a key condition for productive and sustainable value creation at the individual, team, organizational and inter-organizational level. L2C -Learning to Collaborate -is an ongoing research project addressing the design of effective immersive simulation-based learning experiences supporting the development of collaboration competencies both at the individual and organizational level. The key characteristic of such advanced learning tools consists in the integration of psychological, motivational, cognitive, organizational, cultural and technological factors affecting the success or failure of collaboration into the modeling of a set of virtual characters with whom learners can interact dynamically within a challenging and realistic collaboration scenario. This paper provides an overview of the conceptual basis, key design principle s and expected pedagogical impact of this new type of immersive simulation-based learning experience.
Disability & Society, 2009
... View all references; Priestley 200129. Priestley, M. 2001. ... It focuses on their behaviour ... more ... View all references; Priestley 200129. Priestley, M. 2001. ... It focuses on their behaviour rather than on the structure of society and its inequalities (Burton and Kagan 20066. Burton, M. and Kagan, C. 2006. Decoding Valuing people . Disability & Society , 21(4): 299313. ...
Quarterly Journal of Experimental Psychology, 2009