An Empirical Test of Three Alternative Explanations for Covert Reinforcement Effects

1979 ◽  
Vol 44 (2) ◽  
pp. 611-622 ◽  
Author(s):  
Steve H. Sanders ◽  
David Hammer
Keyword(s):  
Positive Reinforcement ◽  
Alternative Explanation ◽  
Instrumental Conditioning ◽  
Empirical Test ◽  
Female Students ◽  
Behavioral Measures ◽  
Empirical Validity ◽  
Treatment Conditions ◽  
All Treatment ◽  
Assessment Results

The empirical validity of the explanations, instrumental-conditioning, counterconditioning, and exposure for covert reinforcement were tested. 45 female students, aged 19 to 35 yr., were subjects. Each was screened for level of fear toward snakes and ability to form clear images. They were randomly assigned to one of five treatment conditions and one of three categories of expectancy. Conditions were covert positive reinforcement, reversed covert positive reinforcement, neutral consequence, reversed covert positive reinforcement to nonsnake stimuli, and nondirective contact. Assessment of expectancy occurred pretreatment and posttreatment, posttreatment only, and no assessment. Results showed that assessment of expectancy did not affect performance on subjective or behavioral measures of fear. All treatment conditions except contact produced significant reductions in fear and increased expectations about ability to approach a live snake. Findings did not support the explanations of instrumental-conditioning, counterconditioning, or exposure. A cognitive-mediational account was offered as an alternative explanation for effects of covert reinforcement.

scholarly journals Effects of White Potato Preparation on Subjective Appetite, Food Intake and Glycemic Response in Healthy Older Adults (P08-083-19)

2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Jennifer Lee ◽  
Robena Amalraj ◽  
Neil Brett ◽  
Sarah Proteau ◽  
Alexander Schwartz ◽  
...  
Keyword(s):  
Older Adults ◽  
Food Intake ◽  
Glycemic Response ◽  
Short Term ◽  
White Potato ◽  
Healthy Older Adults ◽  
Meal Skipping ◽  
Treatment Conditions ◽  
Ad Libitum ◽  
All Treatment

Abstract Objectives Although some epidemiological studies have linked potato consumption to obesity, diabetes, and mortality, there are limited studies on the effects of potatoes on appetite, food intake, and glycemic regulation in older adults. Therefore, the objective was to compare the effects of white potato preparation on subjective appetite, short-term food intake, and glycemic response in healthy older adults (>65 y). Methods Using a within-subject, repeated-measures design, 20 participants (age: 70.5 ± 0.7 y; BMI: 24.2 ± 0.6 kg/m2) completed five treatment conditions. Following an overnight fast, participants completed five treatment conditions (∼283 kcal) of baked potatoes, mashed potatoes, fried French fries, white bread, or continued to fast. Treatment meals were matched for available carbohydrates (33.1 g) and total fat (13.7 g). Subjective appetite and glycemic response were measured at baseline and over 120 min post-meal consumption using visual analogue scales and capillary blood samples, respectively. An ad libitum pizza lunch was provided to measure food intake at 120 min. Results Change from baseline subjective appetite and subjective appetite incremental area under the curve (iAUC) were lower after all treatment meals compared with meal skipping (P < 0.01). Ad libitum pizza lunch food intake was lower after all treatment meals compared with meal skipping by 175–215 kcal (P < 0.02). However, cumulative food intake (treatment meal + ad libitum food intake) did not differ among test conditions (P = 0.26). Change from baseline blood glucose and blood glucose iAUC were higher after all treatment meals compared with meal skipping (P < 0.001), but did not differ from each other. Conclusions White potatoes suppressed subjective appetite and short-term food intake compared with meal skipping, suggesting that white potatoes do not bypass regulatory control mechanisms of energy intake in healthy older adults. Funding Sources Alliance for Potato Research & Education.

Intracellular pH regulation in neurons from chemosensitive and nonchemosensitive regions of Helix aspersa

2000 ◽  
Vol 279 (2) ◽  
pp. R414-R423 ◽  
Author(s):  
Jonathan I. Goldstein ◽  
James M. Mok ◽  
Christopher M. Simon ◽  
J. C. Leiter
Keyword(s):  
Brain Stem ◽  
Intracellular Ph ◽  
Ph Regulation ◽  
Helix Aspersa ◽  
Phylogenetic Distance ◽  
Hypercapnic Acidosis ◽  
Intracellular Ph Regulation ◽  
Treatment Conditions ◽  
Snail Helix Aspersa ◽  
All Treatment

We used 2′,7′-bis(carboxyethyl)-5(6)-carboxyflourescein (BCECF), a pH-sensitive fluorescent dye, to study intracellular pH (pHi) regulation in neurons in CO2chemoreceptor and nonchemoreceptor regions in the pulmonate, terrestrial snail, Helix aspersa. We studied pHiduring hypercapnic acidosis, after ammonia prepulse, and during isohydric hypercapnia. In all treatment conditions, pHifell to similar levels in chemoreceptor and nonchemoreceptor regions. However, pHi recovery was consistently slower in chemoreceptor regions compared with nonchemoreceptor regions, and pHi recovery was slower in all regions when extracellular pH (pHe) was also reduced. We also studied the effect of amiloride and DIDS on pHi regulation during isohydric hypercapnia. An amiloride-sensitive mechanism was the dominant pHi regulatory process during acidosis. We conclude that pHe modulates and slows pHiregulation in chemoreceptor regions to a greater extent than in nonchemoreceptor regions by inhibiting an amiloride-sensitive Na+/H+ exchanger. Although the phylogenetic distance between vertebrates and invertebrates is large, similar results have been reported in CO2-sensitive regions within the rat brain stem.

Effects of Feedback and Reinforcement in Tachistoscopic Training on a Fault-Detection Task

1980 ◽  
Vol 51 (3) ◽  
pp. 987-993
Author(s):  
Jose Bustamante ◽  
Patricio Moreno ◽  
Lucio Rehbein ◽  
Aldo Vizueta
Keyword(s):  
Fault Detection ◽  
Positive Reinforcement ◽  
Stimulus Presentation ◽  
Detection Task ◽  
Control Group ◽  
Treatment Conditions ◽  
Group A ◽  
Recorded Data ◽  
Group 2 ◽  
Effects Of Feedback

This study looked at possible differential effects of feedback and reinforcement on a simulated fault-detection task. Volunteer college students, 11 females and 13 males, participated in the study. Subjects were assigned to three different groups and tachistoscopically presented with series of slides of intact and faulty cups randomly arranged. Subjects in Group 1 were shown a highly preferred slide following each correct detection (positive reinforcement). In Group 2, subjects received a second, longer presentation of every item responded to and every critical one omitted (knowledge of results). Subjects in Group 3 faced a blank screen during inter-stimulus intervals (practice control). Detection scores along five decreasing stimulus presentation times were recorded. Data indicate the treatment conditions as equally efficient and significantly better than the control condition. However, performance of the control group did improve significantly throughout training which suggests the use of tachistoscope as a training device per se. Commission and omission errors did not differ significantly within treatments, though both types of error were significantly elevated for the control group. A possible dissociation between the effects of reinforcers and feedback is discussed, and experiments which would tax higher levels of information processing are suggested to probe this issue further.

Effect of Long-Term Exposure to Acidf Aluminum, and Low Calcium on Adult Brook Trout (Salvelinus fontimlis). 2. Vitellogenesss and Osmoregulation

1988 ◽  
Vol 45 (9) ◽  
pp. 1633-1642 ◽  
Author(s):  
D. R. Mount ◽  
J. R. Hockett ◽  
W. A. Gern
Keyword(s):  
Brook Trout ◽  
Salvelinus Fontinalis ◽  
Plasma Osmolality ◽  
Low Ph ◽  
Reproductive Physiology ◽  
Treatment Conditions ◽  
Plasma Estradiol ◽  
Survival And Growth ◽  
All Treatment

Adult brook trout (Salvelinus fontinalis) were exposed for 193 d (previtellogenesis to spawning) to six combinations of acid, Al, and low Ca. Survival and growth were reduced by low pH combined with low Ca concentrations. After 41 d of exposure, fish in ail low pH exposures showed depressed plasma osmolality and Na concentrations, but by day 97 this apparent osmoregulatory stress was compensated for in all but the most severe treatment (pH 4.97, 47 μg inorganic Al/L, 0.5 mg Ca/L). At the observed peak of yolking (day 147), fish exposed to this treatment also had mean concentrations of plasma estradiol, vitellogenin, and Ca of only half control values. Fecundity (eggs per female) was significantly reduced as well, but this reduction was due in part to decreased growth. Despite these abnormalities in ionoregulatory and reproductive physiology, fish in all treatment conditions produced mature eggs. Among fish in stressful conditions, individual variation in growth and physiological parameters appeared to be correlated with osmoregulatory status. We hypothesize that the suite of physiological disturbances observed are linked to osmoregulatory impairment.

Interfaces in β–SiC whiskers/6061 aluminum composites

1993 ◽  
Vol 8 (10) ◽  
pp. 2569-2576 ◽  
Author(s):  
Katsuaki Suganuma
Keyword(s):  
Squeeze Casting ◽  
Matrix Composites ◽  
Interface Microstructure ◽  
Alloy Matrix ◽  
Treatment Conditions ◽  
Transmission Electron ◽  
Heat Treated ◽  
Sic Whiskers ◽  
Direct Lattice ◽  
All Treatment

6061 alloy matrix composites reinforced with β–SiC whiskers were fabricated both by squeeze casting and by hot-pressing and were heat-treated in the temperature range between 600 °C and 800 °C. The changes in interface microstructure were observed by transmission electron microscopy. In all treatment conditions, no special reaction product, e.g., Al4C3, were observed except for fine γ–Al2O3 particles adhering to the whiskers. A direct lattice connection at the whiskers/matrix interfaces was observed in all composites. β–SiC whiskers were proved to be quite stable in the 6061 matrix.

scholarly journals INFLUENCE OF TIME AND HEAT TREATMENT TEMPERATURE ON PERMEABILITY OF Eucalyptus grandis WOOD

2019 ◽  
Vol 43 (3) ◽  
Author(s):  
Fabiana Paiva de Freitas ◽  
Ana Márcia Macedo Ladeira Carvalho ◽  
Angélica de Cássia Oliveira Carneiro ◽  
Benedito Rocha Vital ◽  
Lira Maria Sivieiro Gonçalves ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Heat Treatment Temperature ◽  
Eucalyptus Grandis ◽  
Treatment Temperature ◽  
Permeability Characteristics ◽  
Treatment Conditions ◽  
Length Width ◽  
Processing Techniques ◽  
All Treatment

ABSTRACT Due to the fact that raw timber has permeability characteristics unsuitable for some applications, several processing techniques have been developed, such as hydrothermal treatments and freezing, which aim to improve these properties. The objective of this study was to analyze the effects of treatment temperature and duration on the permeability of Eucalyptus grandis wood. Heartwood samples from three E. grandis trees were utilized, each with the dimensions 30 x 8 x 3 (length, width, thickness). The treatments were carried out at three temperatures (-20°C, 60°C, and 100°C) and three exposure durations (5, 10, and 15 hours). Treatments at -20°C were conducted inside a domestic freezer, while treatments at 60°C and 100°C took place inside a Parr Reactor, while the wood being submerged in water. Extractive removal was only observed at the surface and interior of wood treated at 60°C and 100°C; while all treatment conditions increased permeability with respect to control treatments.

Pavlovian and Instrumental Conditioning

2021 ◽  
Author(s):  
Federico Sanabria
Keyword(s):  
Conditional Probability ◽  
Positive Reinforcement ◽  
Negative Reinforcement ◽  
Instrumental Conditioning ◽  
Prior Experience ◽  
Time Interval ◽  
Inhibitory Conditioning ◽  
The Difference ◽  
Contextual Stimuli ◽  
Societal Problems

Conditioning is the change in the response to a stimulus either because of the relation of that stimulus to other stimuli (Pavlovian conditioning), or because of the relation between the response and other stimuli (instrumental conditioning). These relations are formulated in terms of differences in conditional probability known as contingencies. Pavlovian contingencies refer to the difference in the conditional probability of one stimulus (the outcome, or O) given the presence vs. the absence of another stimulus (the conditioned stimulus, or CS). A conditioned response (CR) may be strengthened by a positive Pavlovian contingency (excitatory conditioning) or it may be weakened by a negative Pavlovian contingency (inhibitory conditioning). CRs are anticipatory or modified responses to the O, so their topography depends on the nature of the O (appetitive vs. aversive); the proximity between and congruency of O and CS; prior experience with the CS, O, and their contingency; the magnitude of their contingency; and the characteristics of other stimuli in the environment. Instrumental contingencies refer to the relation between one stimulus (the discriminative stimulus, or SD), a response (or operant, R), and the outcome of that response (O). The nature of the O and of its contingency with the R determines whether the O strengthens or weakens the R: Os that introduce an appetitive stimulus (positive reinforcement) or remove an aversive stimulus (negative reinforcement) strengthen the R. Positive reinforcement is typically arranged on a subset of one or more Rs following a set of rules known as a schedule of reinforcement. The probability that an R is reinforced may depend on the number of Rs (ratio schedules) or the amount of time (interval schedules) since the last reinforcer. The topography and strength of instrumental Rs depend on variables that are analogous to those that affect Pavlovian CRs: the amount and nature of prior experience with the O; the proximity, congruency, and contingency of R and O; and characteristics of other stimuli in past and present environments. Contemporary quantitative models of Pavlovian and instrumental conditioning recognize the importance of contextual stimuli that compete for cognitive and behavioral resources, constraining and shaping the expression of target responses. These models have guided the bulk of recent empirical research and conceptual developments, leading to a progressively unified view of learning and motivation processes. Along the way, Pavlovian and instrumental research have demonstrated their utility in addressing a broad range of consequential societal problems.

Higher levels of intrinsic motivation are related to higher levels of class performance for male but not female students

2013 ◽  
Vol 37 (3) ◽  
pp. 227-232 ◽  
Author(s):  
Ronald N. Cortright ◽  
Heidi L. Lujan ◽  
Amanda J. Blumberg ◽  
Julie H. Cox ◽  
Stephen E. DiCarlo
Keyword(s):  
Intrinsic Motivation ◽  
Classroom Practice ◽  
Student Attitudes ◽  
Exercise Physiology ◽  
Perceived Competence ◽  
Female Students ◽  
Male Students ◽  
Behavioral Measures ◽  
Perceived Choice ◽  
Intrinsic Motivation Inventory

Our students are naturally curious, with powerful intrinsic motives to understand their world. Accordingly, we, as teachers, must capitalize on this inherently active and curious nature so that learning becomes a lifelong activity where students take initiative for learning, are skilled in learning, and want to learn new things. Achieving this goal requires an understanding of student attitudes, beliefs, characteristics, and motivations. To achieve this goal, we administered the intrinsic motivation inventory (IMI) to assess our students' interest and enjoyment, perceived choice, and perceived competence while taking our undergraduate exercise physiology class (46 students; 20 female students and 26 male students). The interest and enjoyment subscale is considered the self-reported measure of intrinsic motivation. The perceived choice and perceived competence concepts are theorized to be positive predictors of both self-reported and behavioral measures of intrinsic motivation. Our results documented a significant increase in course grade with an increase in survey score for the interest and enjoyment subscale of the IMI when female and male students were combined. Specifically, each increase in survey score for the interest and enjoyment subscale of the IMI was associated with a significant ( P < 0.05) increase of 3.9% in course grade. However, the increase in survey score was associated with a significantly greater ( P < 0.05) increase in course grade for male (6.1%) compared with female (0.3%) students. These results have implications for both classroom practice and educational reform policies.

scholarly journals The use of operant instrumental conditioning with positive reinforcement for collection of saliva from marmosets (Callithrix jacchus) for research purposes

2013 ◽  
Author(s):  
Myrna Campos Ferraz ◽  
André Vicente Ruiz de Matos ◽  
Carlos Roberto Teixeira ◽  
Bruna Silva Miranda ◽  
Lygia Karla Sanches Francelino ◽  
...  
Keyword(s):  
Positive Reinforcement ◽  
Instrumental Conditioning ◽  
Callithrix Jacchus
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