Learning-related shifts in generalization gradients for complex sounds

Learning to discriminate stimuli can alter how one distinguishes related stimuli. For instance, training an individual to differentiate between two stimuli along a single dimension can alter how that individual generalizes learned responses. In this study, we examined the persistence of shifts in generalization gradients after training with sounds. University students were trained to differentiate two sounds that varied along a complex acoustic dimension. The students were subsequently tested on their ability to recognize a sound that they had experienced during training when it was presented among several novel sounds varying along this same dimension. Peak shift was observed in Experiment 1, in which generalization tests immediately followed training, and in Experiment 2, in which the tests were delayed by 24 h. These findings further support the universality of generalization processes across species, modalities, and levels of stimulus complexity. They also raise new questions about the mechanisms underlying learning-related shifts in generalization gradients. The sound stimuli from this study are available as .wav files from http://lb.psychonomic-journals.org/content/supplemental.     

ASSESSING THEINFORMATION NEEDS OF STAFF IN TWO LONG-TERM CARE ORGANIZATIONS

As alternate care levels are transferred from hospital to community settings, health care workers in long term care are caring for individuals where conditions are more medically complex. In response to this situation decision makers in long term care are pursuing the goal of practice based on the best evidence. Identifying the information needs of health care workers in this environment represents the first step towards cultivating a best practice culture in long term care. The purpose of this study was to identify what information resources staff need to improve clinical and managerial decision making. The perceptions of health care workers at two long term care organizations were investigated through quantitative and qualitative methods, using a questionnaire and focus groups. In each of the settings there were gaps in the availability of resources and perceived needs for education. The findings from both settings revealed the need for more information resources to assist staff to improve individual care of residents and develop better approaches to health problems.     

Stimulus control in multiple temporal discriminations

In multiple fixed interval (FI) schedules, rats are trained to discriminate different FIs that are signaled by different stimuli. After extensive training, the different stimuli often acquire control over performance, observed by an earlier increase in responding for stimuli that signal shorter FIs, as compared with stimuli that signal longer FIs. The order in which the different FIs are trained, either intermixed across cycles or in blocks of several cycles, may seem irrelevant given that average performance at asymptote may be similar. In this study, rats were trained in two procedures with multiple FIs presented intermixed within sessions or in blocks of one interval per session. Similar performance was observed at asymptote, but an inspection of early cycles in each session revealed that different stimuli acquired control over performance only when trained intermixed within each session. Although the stimuli reliably signaled the upcoming FI, when trained in successive blocks of 60 cycles, rats rapidly adjusted performance early in the sessions on the basis of the temporal aspects of the task, and not on the basis of the stimulus presented in the current cycle. These results are discussed in terms of overshadowing of the stimuli by temporal cues and in terms of conditions under which a stimulus acquires control over performance.     

Proponents of Creationism but not Proponents of Evolution Frame the Origins Debate in Terms of Proof

In Study 1, 72 internet documents containing creationism, ID (intelligent design), or evolution content were selected for analysis. All instances of proof cognates (the word “proof” and related terms such as “proven”, “disproof”, etc.) contained within these documents were identified and labeled in terms of the manner in which the terms were used. In Study 2, frequency counts for six terms (proof, evidence, establish, experiment, test, trial) were conducted on a sample of peer-reviewed research articles in the journal Science and the 72 internet documents included in Study 1. Quantitative and qualitative analyses revealed that proponents of creationism were much more likely than proponents of evolution to frame the creationism/evolution issue in terms of proof (ID proponents fell partway between the other two). Proponents of creationism frequently described empirical data favoring their position as proof of their position. Even more frequently, proponents of creationism described evolutionary scientists as being engaged in failed attempts to prove the truth of the evolutionary position. Evolution documents included fewer proof cognates than creationism or ID documents and the few proof cognates found in evolution documents were rarely used to describe the status of the theory of evolution. Qualitative data analysis indicated that proof cognates were often used to indicate certainty. The asymmetry between evolution and creationism documents was limited primarily to proof cognates; there were no major asymmetries for the terms evidence, establish, experiment, test, and trial. The results may reveal differences in the epistemological commitments of the involved parties.     

Early Childhood Educators’ Wellbeing During the COVID-19 Pandemic

Early Childhood Education Journal - The importance of Early Childhood (EC) educators’ wellbeing has been brought into sharp focus during the COVID-19 pandemic, as educators have navigated...     

Integrated electrical concentration and lysis of cells in a microfluidic chip

Lysing cells is an important step in the analysis of intracellular contents. Concentrating cells is often required in order to acquire adequate cells for lysis. This work presents an integrated concentration and lysis of mammalian cells in a constriction microchannel using dc-biased ac electric fields. By adjusting the dc component, the electrokinetic cell motion can be precisely controlled, leading to an easy switch between concentration and lysis of red blood cells in the channel constriction. These two operations are also used in conjunction to demonstrate a continuous concentration and separation of leukemia cells from red blood cells in the same microchannel. The observed cell behaviors agree reasonably with the simulation results.