The Role of Tacit Routines in Coordinating Activity

We explore the influence of tacit routines in obtaining coordination. Our experiment uses simple laboratory "firms," in which we interfere with one kind of firm's ability to develop tacit routines. Thus, our firms vary in the degree to which they rely on this kind of knowledge – instead of other, explicit, mechanisms – for obtaining coordination. We find that interfering with the development of tacit routines harms firms’ ability to coordinate. We then explore the extent to which firms are able to transfer their ability to coordinate activity, either to a new domain or to new members. Our results indicate that tacit routines transfer more easily than other mechanisms to a new, but closely related, domain. However, routine-based firms perform slightly worse in their ability to incorporate new members

Nicotine Enhances Operant Responding for Qualitatively Distinct Reinforcers Under Maintenance and Extinction Conditions

RATIONALE—Nicotine enhancement of reward has been implicated as an important contributor to tobacco addiction. Despite the attention that reward enhancement has received, the behavioral mechanisms whereby nicotine enhances operant responding remain largely unknown. The present study sought to extend previous work by evaluating the effects of nicotine on responding for two qualitatively different rewards (visual stimulation (VS) and 4% sucrose solution) under fixed-ratio (FR) maintenance and extinction conditions. METHOD—Sprague-Dawley rats were trained to press an active lever for VS (Experiment 1) or 4% sucrose solution (Experiment 2) and evaluated over 15 sessions on a FR5 schedule of reinforcement. Nicotine (0.4 mg base/kg, SC) or saline were administered 5 min before each session; the alternate solution was given in the home cage after the session. The effects of nicotine on extinction responding were then assessed over 5 sessions and rats were divided into 4 groups based on drug of injection received during FR-maintenance and extinction phases (Maintenance- Extinction): Nic-Nic, Nic-Sal, Sal-Sal, and Sal-Nic. RESULTS—Nicotine increased active lever response rates for both VS and 4% sucrose under FR5 maintenance conditions. Nicotine also increased response rates in the Nic-Nic group relative to all other groups under extinction conditions in both experiments, though this effect had greater longevity following VS maintenance conditions than sucrose. Enhancement of responding during extinction does not appear dependent upon locomotor activation by nicotine

A quantitative analysis of the reward-enhancing effects of nicotine using reinforcer demand

Reward enhancement by nicotine has been suggested as an important phenomenon contributing toward tobacco abuse and dependence. Reinforcement value is a multifaceted construct not fully represented by any single measure of response strength. The present study evaluated the changes in the reinforcement value of a visual stimulus in 16 male Sprague–Dawley rats using the reinforcer demand technique proposed by Hursh and Silberberg. The different parameters of the model have been shown to represent differing facets of reinforcement value, including intensity, perseverance, and sensitivity to changes in response cost. Rats lever-pressed for 1-min presentations of a compound visual stimulus over blocks of 10 sessions across a range of response requirements (fixed ratio 1, 2, 4, 8, 14, 22, 32). Nicotine (0.4 mg/kg, base) or saline was administered 5 min before each session. Estimates from the demand model were calculated between nicotine and saline administration conditions within subjects and changes in reinforcement value were assessed as differences in Q0, Pmax, Omax, and essential value. Nicotine administration increased operant responding across the entire range of reinforcement schedules tested, and uniformly affected model parameter estimates in a manner suggesting increased reinforcement value of the visual stimulus

A quantitative analysis of the reward-enhancing effects of nicotine using reinforcer demand

Reward enhancement by nicotine has been suggested as an important phenomenon contributing toward tobacco abuse and dependence. Reinforcement value is a multifaceted construct not fully represented by any single measure of response strength. The present study evaluated the changes in the reinforcement value of a visual stimulus in 16 male Sprague–Dawley rats using the reinforcer demand technique proposed by Hursh and Silberberg. The different parameters of the model have been shown to represent differing facets of reinforcement value, including intensity, perseverance, and sensitivity to changes in response cost. Rats lever-pressed for 1-min presentations of a compound visual stimulus over blocks of 10 sessions across a range of response requirements (fixed ratio 1, 2, 4, 8, 14, 22, 32). Nicotine (0.4 mg/kg, base) or saline was administered 5 min before each session. Estimates from the demand model were calculated between nicotine and saline administration conditions within subjects and changes in reinforcement value were assessed as differences in Q0, Pmax, Omax, and essential value. Nicotine administration increased operant responding across the entire range of reinforcement schedules tested, and uniformly affected model parameter estimates in a manner suggesting increased reinforcement value of the visual stimulus

Circumpolar Diversity and Geographic Differentiation of mtDNA in the Critically Endangered Antarctic Blue Whale (Balaenoptera musculus intermedia)

To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work.\ud This is the publisher’s final pdf. The published article is copyrighted by the Public Library of Science and can be found at: http://www.plosone.org/home.action.The Antarctic blue whale (Balaenoptera musculus intermedia) was hunted to near extinction between 1904 and 1972, declining from an estimated initial abundance of more than 250,000 to fewer than 400. Here, we describe mtDNA control region diversity and geographic differentiation in the surviving population of the Antarctic blue whale, using 218 biopsy samples collected under the auspices of the International Whaling Commission (IWC) during research cruises from 1990-2009. Microsatellite genotypes and mtDNA sequences identified 166 individuals among the 218 samples and documented movement of a small number of individuals, including a female that traveled at least 6,650 km or 131 degrees longitude over four years. mtDNA sequences from the 166 individuals were aligned with published sequences from 17 additional individuals, resolving 52 unique haplotypes from a consensus length of 410 bp. From this minimum census, a rarefaction analysis predicted that only 72 haplotypes (95% CL, 64, 86) have survived in the contemporary population of Antarctic blue whales. However, haplotype diversity was relatively high (0.968 +/- 0.004), perhaps as a result of the longevity of blue whales and the relatively recent timing of the bottleneck. Despite the potential for circumpolar dispersal, we found significant differentiation in mtDNA diversity (F-ST = 0.032, p<0.005) and microsatellite alleles (F-ST = 0.005, p<0.05) among the six Antarctic Areas historically used by the IWC for management of blue whales

The intermediate alternative effect: Considering a small tradeoff increases subsequent willingness to make large tradeoffs

Prior research has consistently demonstrated that people are reluctant to trade a good they own for an alternative good, particularly when the alternative (or “target”) represents a substantial departure from the “endowment”. We demonstrate that the endowment effect can be reduced by first making participants consider trading their endowment for an intermediate alternative (which shares some characteristics of the endowment and some characteristics of the target). We find that this “intermediate alternative effect” operates primarily by shifting one’s reference point in the direction of the target alternative. Even when the intermediate alternative is not adopted, the extent to which one’s endowment is treated as a reference point is weakened, which can also facilitate subsequent trading.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141910/1/jcpy384.pd

Examining the Reinforcement-Enhancement Effects of Phencyclidine and Its Interactions with Nicotine on Lever-Pressing for a Visual Stimulus

Nicotine is a widely-abused drug, yet its primary reinforcing effect does not seem potent as other stimulants such as cocaine. Recent research on the contributing factors toward chronic use of nicotine-containing products has implicated the role of reinforcement-enhancing effects of nicotine. The present study investigates whether phencyclidine (PCP) may also possess a reinforcement-enhancement effect and how this may interact with the reinforcement-enhancement effect of nicotine. PCP was tested for two reasons: 1) it produces discrepant results on overall reward, similar to that seen with nicotine and 2) it may elucidate how other compounds may interact with the reinforcement-enhancement of nicotine. Adult male Sprague-Dawley rats were trained to lever press for brief visual stimulus presentations under fixed-ratio (FR) schedules of reinforcement and then were tested with nicotine (0.2 or 0.4 mg/kg) and/or PCP (2.0 mg/kg) over six increasing FR values. A selective increase in active lever-pressing for the visual stimulus with drug treatment was considered evidence of a reinforcement-enhancement effect. PCP and nicotine separately increased active lever pressing for a visual stimulus in a dose-dependent manner and across the different FR schedules. The addition of PCP to nicotine did not increase lever-pressing for the visual stimulus, possibly due to a ceiling effect. The effect of PCP may be driven largely by its locomotor stimulant effects, whereas the effect of nicotine was independent of locomotor stimulation. This dissociation emphasizes that distinct pharmacological properties contribute to the reinforcement-enhancement effects of substances

Examining the Reinforcement-Enhancement Effects of Phencyclidine and Its Interactions with Nicotine on Lever-Pressing for a Visual Stimulus

Nicotine is a widely-abused drug, yet its primary reinforcing effect does not seem potent as other stimulants such as cocaine. Recent research on the contributing factors toward chronic use of nicotine-containing products has implicated the role of reinforcement-enhancing effects of nicotine. The present study investigates whether phencyclidine (PCP) may also possess a reinforcement-enhancement effect and how this may interact with the reinforcement-enhancement effect of nicotine. PCP was tested for two reasons: 1) it produces discrepant results on overall reward, similar to that seen with nicotine and 2) it may elucidate how other compounds may interact with the reinforcement-enhancement of nicotine. Adult male Sprague-Dawley rats were trained to lever press for brief visual stimulus presentations under fixed-ratio (FR) schedules of reinforcement and then were tested with nicotine (0.2 or 0.4 mg/kg) and/or PCP (2.0 mg/kg) over six increasing FR values. A selective increase in active lever-pressing for the visual stimulus with drug treatment was considered evidence of a reinforcement-enhancement effect. PCP and nicotine separately increased active lever pressing for a visual stimulus in a dose-dependent manner and across the different FR schedules. The addition of PCP to nicotine did not increase lever-pressing for the visual stimulus, possibly due to a ceiling effect. The effect of PCP may be driven largely by its locomotor stimulant effects, whereas the effect of nicotine was independent of locomotor stimulation. This dissociation emphasizes that distinct pharmacological properties contribute to the reinforcement-enhancement effects of substances

Spendthrifts and Tightwads in Childhood: Feelings about Spending Predict Children’s Financial Decision Making

Adults differ in the extent to which they find spending money to be distressing; “tightwads” find spending money painful, and “spendthrifts” do not find spending painful enough. This affective dimension has been reliably measured in adults and predicts a variety of important financial behaviors and outcomes (e.g., saving behavior and credit scores). Although children’s financial behavior has also received attention, feelings about spending have not been studied in children, as they have in adults. We measured the spendthrift–tightwad (ST–TW) construct in children for the first time, with a sample of 5‐ to 10‐year‐old children (N = 225). Children across the entire age range were able to reliably report on their affective responses to spending and saving, and children’s ST–TW scores were related to parent reports of children’s temperament and financial behavior. Further, children’s ST–TW scores were predictive of whether they chose to save or spend money in the lab, even after controlling for age and how much they liked the offered items. Our novel findings—that children’s feelings about spending and saving can be measured from an early age and relate to their behavior with money—are discussed with regard to theoretical and practical implications. Copyright © 2017 John Wiley & Sons, Ltd.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/144659/1/bdm2071_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/144659/2/bdm2071.pd