Pigeons' reactivity to food and to Pavlovian signals for food in a closed economy: Effects of feeding time and signal reliability.

Studied feeding behavior and responses to Pavlovian signals for food of 6 naive pigeons (Columba livia) in a 24-hr closed economy, in 2 experiments. The Ss could initiate a feeding sequence at any time during the light period of the 12 hr–22 hr light–dark cycle by pressing on a foot treadle. Six treadle presses produced 1 of 3 conditioned stimulus/stimuli (CS) colors on the response key; the colors signaled different probabilities of food access (1.0, 0.5, or 0) at the end of the 10-sec CS. Food-access time was varied across phases (Exp I) and from day to day (Exp II) but was always constant within a day. The results indicate that the effect of 50% signal reliability was negligible at all but the longest hopper durations, where pecking was somewhat weaker to the 50% signal than to the 100% signal. Keypecking rate, rate of eating from the food hopper, and number of trials produced each day were inversely related to the duration of hopper presentations. Time spent eating, amount of food eaten, and body weight were directly related to hopper duration. An inverse relation between keypecking rate and hopper duration has not previously been reported in Pavlovian experiments where unconditioned stimulus/stimuli (UCS) magnitude is varied. This unique result may be related to the way hopper duration affects feeding behavior in the closed economy. (45 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mechanisms underlying the effects of unsignaled delayed reinforcement on key pecking of pigeons under variable-interval schedules

Three experiments were conducted to test an interpretation of the response-rate-reducing effects of unsignaled nonresetting delays to reinforcement in pigeons. According to this interpretation, rates of key pecking decrease under these conditions because key pecks alternate with hopper-observing behavior. In Experiment 1, 4 pigeons pecked a food key that raised the hopper provided that pecks on a different variable-interval-schedule key met the requirements of a variable-interval 60-s schedule. The stimuli associated with the availability of the hopper (i.e., houselight and keylight off, food key illuminated, feedback following food-key pecks) were gradually removed across phases while the dependent relation between hopper availability and variable-interval-schedule key pecks was maintained. Rates of pecking the variable-interval-schedule key decreased to low levels and rates of food-key pecks increased when variable-interval-schedule key pecks did not produce hopper-correlated stimuli. In Experiment 2, pigeons initially pecked a single key under a variable-interval 60-s schedule. Then the dependent relation between hopper presentation and key pecks was eliminated by arranging a variable-time 60-s schedule. When rates of pecking had decreased to low levels, conditions were changed so that pecks during the final 5 s of each interval changed the keylight color from green to amber. When pecking produced these hopper-correlated stimuli, pecking occurred at high rates, despite the absence of a peck-food dependency. When peck-produced changes in keylight color were uncorrelated with food, rates of pecking fell to low levels. In Experiment 3, details (obtained delays, interresponse-time distributions, eating times) of the transition from high to low response rates produced by the introduction of a 3-s unsignaled delay were tracked from session to session in 3 pigeons that had been initially trained to peck under a conventional variable-interval 60-s schedule. Decreases in response rates soon after the transition to delayed reinforcement were accompanied by decreases in eating times and alterations in interresponse-time distributions. As response rates decreased and became stable, eating times increased and their variability decreased. These findings support an interpretation of the effects of delayed reinforcement that emphasizes the importance of hopper-observing behavior.     

"Attenuation of Gastric Lesions by Psychological Aspects of Aggression in Rats": Erratum.

Reports an error in the original article by Jay M. Weiss, Larissa A. Pohorecky, Sherry Salman, and Michael Gruenthal (Journal of Comparative & Physiological Psychology, 1976[Mar], Vol 90[3], 252-259). The figures on pages 255 and 257 should be reversed as Figure 4 now bears the caption of Figure 3 and vice versa. The figures with their correct captions are provided. (The following abstract of this article originally appeared in record 1976-20292-001.) In a study with 80 male albino rats, Ss that fought with each other in response to electric shock showed reduced gastric lesions in comparison with Ss that received the same shocks alone so that fighting behavior did not occur. Also, gastric lesions were similarly reduced in Ss that fought even though they could not physically contact one another because of a barrier between them. In this case, the "protective" effect of fighting derived from the release or display of fighting behavior and did not require physical combat. A 2nd experiment with 48 rats showed that Ss that received shock together but did not engage in fighting behavior showed no reduction of gastric lesions, so that the protective effect of fighting was not an artifact of Ss receiving shock together. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Studies in spatial learning: I. Orientation and the short-cut.

(This reprinted article originally appeared in the Journal of Experimental Psychology, 1946, Vol 36, 13–24. The following abstract of the original article appeared in PA, Vol 20:2297.) The original rough formulation of the expectancy theory is difficult to distinguish from the alternative stimulus-response doctrines, partly because of the implicit definition of the matrix "x expects a goal at location L" which makes it equivalent to the matrix "x runs down the practiced path" when certain conditions are fulfilled. A substitute definition is suggested which makes the former matrix equivalent to "x runs down the path which points directly to the location L" when certain conditions are fulfilled. To determine whether the class defined by this latter definition has members, 56 "maze-wise" female rats were trained to run in a simple maze to obtain food. When the original path was blocked and a choice among 18 different paths was presented, 36% chose the path pointing directly toward the goal. The other rats chose the other paths in a chance fashion… (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Toward a statistical theory of learning.

(This partially reprinted article originally appeared in Psychological Review, 1950, Vol 57, 94–207. The following abstract of the original article appeared in PA, Vol 24:5093.) An attempt has been made to clarify some issues in current learning theory by giving a statistical interpretation to the concepts of stimulus and response and by deriving quantitative laws that govern simple behavior systems. Dependent variables, in this formulation, are classes of behavior samples with common quantitative properties; independent variables are statistical distributions of environmental events. Laws of the theory state probability relations between momentary changes in behavioral and environmental variables. From this point of view it has been possible to derive simple relations between probability of response and several commonly used measures of learning, and to develop mathematical expressions describing learning in both classical conditioning and instrumental learning situations under simplified conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The physiology of motivation.

(This reprinted article originally appeared in Psychological Review, 1954, Vol 61, 5–22. The following abstract of the original article appeared in PA, Vol 28:7127.) With the assumption that the amount of motivated behavior is a function of the amount of activity in certain excitatory centers of the hypothalamus, a physiological theory of motivated behavior is presented along with supporting evidence from a variety of different motivating situations. The problem of learned motives is also considered. A section on theoretical advantages and limitations concludes the article. 62 references. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Several effects of behavioral cost on pigeons' reactivity to food and to Pavlovian signals for food.

The effects of behavioral cost of obtaining food on pigeons' responsiveness to Pavlovian signals and food were investigated in three free-feeding experiments. During 10-hr sessions a pigeon could produce a 10-s keylight followed by 10-s access to a grain hopper by stepping on a foot treadle. Cost was manipulated by using four different fixed ratio (Experiment 1) or variable ratio (Experiment 2) schedules to vary the number of treadle presses required. The number of consecutive trials on which the cost was low or high was varied in Experiment 3. The rates of keypecking and eating were both found to be positively related to the average cost (Experiments 1 and 2). When cost varied from trial to trial (Experiments 2 and 3), keypecking rate was inversely related to the cost on a trial. Results of Experiment 3 indicated that keypecking tended to decrease over a series of low-cost trials and to increase over a series of high-cost trials. It was proposed that the pigeons continually update their estimate of average cost and that the cost on each trial is compared with that estimate. Furthermore, signal-directed responding (a) is potentiated when cost on a trial is less than the average and (b) is reduced when cost on a trial is greater than the average cost. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"Asymptotically distribution-free (ADF) interval estimation of coefficient alpha": Correction.

Reports an error in "Asymptotically distribution-free (ADF) interval estimation of coefficient alpha" by Alberto Maydeu-Olivares, Donna L. Coffman and Wolfgang M. Hartmann (Psychological Methods, 2007[Jun], Vol 12[2], 157-176). The sentence describing Equation 1 is incorrect. The corrected sentence is presented in the erratum. (The following abstract of the original article appeared in record 2007-07830-003.) The point estimate of sample coefficient alpha may provide a misleading impression of the reliability of the test score. Because sample coefficient alpha is consistently biased downward, it is more likely to yield a misleading impression of poor reliability. The magnitude of the bias is greatest precisely when the variability of sample alpha is greatest (small population reliability and small sample size). Taking into account the variability of sample alpha with an interval estimator may lead to retaining reliable tests that would be otherwise rejected. Here, the authors performed simulation studies to investigate the behavior of asymptotically distribution-free (ADF) versus normal-theory interval estimators of coefficient alpha under varied conditions. Normal-theory intervals were found to be less accurate when item skewness >1 or excess kurtosis >1. For sample sizes over 100 observations, ADF intervals are preferable, regardless of item skewness and kurtosis. A formula for computing ADF confidence intervals for coefficient alpha for tests of any size is provided, along with its implementation as an SAS macro. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"Marking effects in Pavlovian trace conditioning": Correction to Thomas, Robertson, and Lieberman.

Reports an error in "Marking effects in Pavlovian trace conditioning" by Glyn V. Thomas, Derek Robertson and David A. Lieberman (Journal of Experimental Psychology: Animal Behavior Processes, 1987[Apr], Vol 13[2], 126-135). The last sentence in the second paragraph of the Discussion on page 128 should read as follows: "A second possibility is that in the marked ITI group, the marking of irrelevant events in the middle of the intertrial interval promoted associations between those events and food, which then interfered with the learning of an association between SI and food." (The following abstract of the original article appeared in record 1987-24113-001.) In four experiments we investigated pigeons' acquisition of a successive discrimination with a trace autoshaping procedure. The conditioned stimuli were 5-s presentations of colored key lights, one of which was followed by food after a 5-s delay. In Experiment 1, which used spatially defined cues, we found that acquisition of differential responding to the reinforced cue was facilitated when a brief flash of light immediately followed both reinforced and nonreinforced cues. Experiment 2 found a similar enhancement by the added light flash in a purely visual discrimination. Experiment 3 found that the flash facilitated learning only when presented immediately after the discriminative cues, and not when it occurred immediately before the cues or at the time of reinforcement. A fourth experiment found this facilitation effect only when the flash and reinforcement occurred on the same trial. These results are interpreted in terms of marking: The flash enhanced learning because it triggered a backward scan through recent memory to search for possible predictors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"Rhythms and responses": Correction to Kolers and Brewster.

Reports an error in "Rhythms and responses" by Paul A. Kolers and Joan M. Brewster (Journal of Experimental Psychology: Human Perception and Performance, 1985[Apr], Vol 11[2], 150-167). There is a typographical error on page 153. A correction to this error has been provided in the erratum. (The following abstract of the original article appeared in record 1986-05383-001.) Tested the assumption that there is a central clock coordinating behavior in all sensory modalities and response modes. A rhythmic tapping task was used in 3 experiments in which 12 undergraduates first attempted to synchronize responses with brief auditory, tactile, or visual stimuli and then continued to tap at the same rate on their own. Performance was most variable with visual stimuli and least variable with auditory stimuli. Results suggest that performances were not based on a common clock and that different strategies were employed when the task was presented in different modalities. The hypothesis of a single timing mechanism controlling behavior is rejected, and the validity is questioned of information processing models that are formulated without regard to temporal relations among their conjectured processes. Discussion focuses on the relation between successive responses and the means by which timing is accomplished. (56 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"The truly false consensus effect: An ineradicable and egocentric bias in social perception": Correction.

Reports an error in the original article by J. Krueger and R. W. Clement (Journal of Personality and Social Psychology, 1994[Oct], Vol 67[4], 596–610). A correction to the equation on page 605 is provided. (The following abstract of this article originally appeared in PA, Vol 82:5338.) Consensus bias is the overuse of self-related knowledge in estimating the prevalence of attributes in a population. The bias seems statistically appropriate (R. M. Dawes; see record 1989-25841-001), but according to the egocentrism hypothesis, it merely mimics normative inductive reasoning. In Exp 1, Ss made population estimates for agreement with each of 40 personality inventory statements. Even Ss who had been educated about the consensus bias, or had received feedback about actual consensus, or both showed the bias. In Exp 2, Ss attributed bias to another person, but their own consensus estimates were more affected by their own response to the item than by the other person's response. In Exp 3, there was bias even in the presence of unanimous information from 20 randomly chosen others. In all 3 experiments, Ss continued to show consensus bias despite the availability of other statistical information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"Inferences from personnel tests and their validity": Correction to Lawshe.

Reports an error in "Inferences from personnel tests and their validity" by C. H. Lawshe (Journal of Applied Psychology, 1985[Feb], Vol 70[1], 237-238). On page 238, line 4, the word "each" appears and should be "such." The sentence will, therefore, refer "to the use of such cognitive processes as inductive and deductive reasoning and such characteristics of temperament as emotional stability and self-esteem." (The following abstract of the original article appeared in record 1985-16032-001.) Contends that despite clear definitions in standard sources, psychologists persistently refer to the validity of tests instead of the validity of inferences from test scores. This persistence leads to references to "kinds of validity" when, in fact, there are "kinds of validity analysis strategies" whereby data are collected or generated to determine or defend the extent, degree, or strength of the inference or inferences that can be made from a set of test scores. It is concluded that content validity analysis strategies are appropriate only when the job behavior under scrutiny falls at the observation end of the continuum; when such behavior approaches the abstract end of the continuum, a construct validity analysis strategy is indicated. (5 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"Gender differences in interaction style and influence": Correction.

Reports an error in the original article by L. L. Carli (Journal of Personality and Social Psychology, 1989, [Apr] Vol 56[4], 565–576). On page 567, the 3rd sentence in the Procedure section should read, "Half of the subjects were paired with same-sex partners and half with opposite-sex partners, resulting in 16 female pairs, 16 male pairs, and 32 mixed-sex pairs.' On page 568, the equation at the bottom of the left-hand column should read as follows: (Mfs?–?Mms?–?Mfm?+?Mmm)/((2MSe?+ &2MS′e)(1/n))?. (The following abstract of this article originally appeared in record 1989-25837-001.) Observed 128 Ss in mixed- and same-sex dyads to examine effects of interaction on sex differences in influence. Ss discussed 2 topics on which they disagreed. During the 2nd discussion, 1 S in each pair was told to influence the other. Ss showed more agreement and positive social behavior when paired with a woman and more disagreement and task behavior when paired with a man. Although… (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Complement consuming antibodies against a modified human serum protein in pigeon breeders' disease

The sera of patients with pigeon breeders' disease contain precipitating and human complement consuming antibodies against pigeon dropping antigens. Cessation of antigen exposure results in a decrease of precipitins below the level of detection in immunodiffusion. Complement consuming antibodies remain present, however, despite antigen avoidance. A close correlation is observed between human complement consumption tests with pigeon dropping antigens PDF1-A or pigeon cropmilk IgA and a modified human serum gamma-globulin. Isolation of this protein is readily achieved by its non-specific adsorption onto activated Sepharose 4B and subsequent elution with 1 M acetic acid. This modified protein may act as an autoantigen in pigeon breeders' disease, maintaining human complement consuming antibodies for years in subjects with no further bird antigen contact.     

"Does motor programming necessitate response execution?": Correction.

Reports an error in the original article by A. Osman et al (Journal of Experimental Psychology: Human Perception and Performance, 1990, Vol 16[1], 183–298). In Table 3 on page 192, 2 responses for high-complexity sequences should read "1 Ri?+?3 Li or 1 Li?+?3 Ri.' (The following abstract of this article originally appeared in record 1990-13808-001.) The complexity of a movement is known to affect the time it takes to initiate the movement. This effect is thought to reflect changes in the duration of processes that operate on a motor program. This question addressed here is whether programming a movement compels the start of its overt execution. If it does, then the programming processes may be said to occur after the "point of no return.' We report results from an empirical procedure and a theoretical analysis designed to study processes before and after this point separately. According to our results, changes in the complexity of a movement affect only the prior set of processes. From this we argue that motor programming does not necessitate response execution and that the point of no return occurs very late in the information-processing system. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"Dynamic testing": Erratum.

Reports an error in the original article by E. L. Grigorenko and R. J. Sternberg (Psychological Bulletin, 1998[Jul], Vol 124[1], 75–111). The original article contained a word-processing error that resulted in an incorrect word substitution in the reference list. Corrections to the references are listed. (The following abstract of this article originally appeared in record 1998-04232-004.) This article evaluatively reviews the literature on dynamic testing, a collection of testing procedures designed to quantify not only the products or even the processes of learning but also the potential to learn. The article considers a variety of approaches to dynamic testing and the strengths and weaknesses of each. Moreover, the literature on each approach is reviewed and analyzed in terms of the extent to which it fulfills the claims made for it. In all of these approaches, testing involves learning at the time of test, rather than just static testing of what has been learned before. It is concluded that dynamic testing has great potential for helping to understand people's potentials but that its potential has yet to be realized fully. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"Not to be and then to be: Visual representation of ignored unfamiliar faces": Erratum.

Reports an error in "Not to be and then to be: Visual representation of ignored unfamiliar faces" by Beena Khurana, W. C. Smith and M. T. Baker (Journal of Experimental Psychology: Human Perception and Performance, 2000[Feb], Vol 26[1], 246-263). Beena Khurana was listed as the sole author in the original article. Dr. Khurana has indicated that the following names should have been included as authors: W. Carter Smith and Margaret T. Baker. The correct citation for the article should be Khurana, B., Smith, W. O, & Baker, M. T. (2000). Not to be and then to be: Visual representation of ignored unfamiliar faces. Journal of Experimental Psychology: Human Perception and Performance, 26, 246-263. The author note should include the following information: Experiments 1-4 made up a first-year graduate research project that was funded by a Cornell University Sage Graduate Fellowship to W. Carter Smith. (The following abstract of the original article appeared in record 2000-13210-015.) Negative priming, the increase in response time and/or errors to targets previously encountered as distractors, is explained by inhibitory mechanisms that block the access of distractor representations to response systems. The processing of unfamiliar human faces was investigated using negative priming. Observers viewed a row of faces to decide whether 2 target faces were the same or different. Response latencies were longer when 1 or both targets had appeared as distractors on the immediately preceding trial--evidence that never-before seen faces are represented and require inhibition. Response latencies were shorter when face targets had appeared as distractors, either corrupted with high-frequency noise or contrast inverted-evidence that representations are facilitated. Finally, response latencies remained unaltered when face targets had appeared as upside-down distractors--evidence that not all distractor representations afford response priming. The visual system indeed represents ignored unfamiliar faces, but blocks these representations only if they vie with targets for the control of action. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Environmental constraints on motor abilities used in grooming, swimming, and eating by decorticate rats.

Successive tests reexamined the grooming, swimming, and eating behaviors of 20 decorticate male Long-Evans rats by evoking the behaviors in various circumstances (stimulus conditions). Ss showed normal-length grooming sequences during spontaneous home cage grooming; when grooming was elicited by removing them from their home cage and soaking their fur by a brief swim, grooming sequences were shorter. In cold water (18°C), Ss swam well and with exaggerated vigor and frequently inhibited forelimb movements; in warm water (37°C), they swam poorly and paddled with all 4 limbs. To eat small pieces of food, Ss sat up and used forepaws as do normal rats, but they frequently dropped the food; they did not use their forepaws to eat large pieces of food. When given powdered food, they first tried to grasp it in their mouth while they scratched at the floor surface with their front limbs; thereafter, they became increasingly proficient in licking it up. Thus, in a narrow range of stimulus conditions, decorticate rats can make movements resembling those of normal ones. They also improve with practice in some tasks but not in others. In order to elucidate the role of the cortex in control of motor behavior, it is considered necessary to obtain "behavior profiles" of each behavior by testing the animals repeatedly and under widely varying test conditions. (36 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"Does violence beget violence? A critical examination of the literature": Clarification of publishing history.

Alerts APA researchers and readers that the article "Does violence beget violence? A critical examination of the literature" by C. S. Widom (Psychological Bulletin, 1989, Vol 106(1), Jul, 3–28) has been amplified and reprinted in a book chapter: Widom, C. S. (1989). The intergenerational transmission of violence. In N. A. Weinger & M. E. Wolfgang (Eds.), Pathways to criminal violence. Newbury Park, CA: Sage. Through an oversight, cross-reference between the two publications and information in the copyright for this article were omitted from the Sage book. The copyright is held by the American Psychological Association. (The following abstract of this article originally appeared in PA, Vol 76:36811.) Critically examines the "violence breeds violence" hypothesis broadly defined. Organized into 7 sections, the literature review includes (a) the abuse breeds abuse hypothesis; (b) reports of small numbers of violent/homicidal offenders; (c) studies examining the relationship of abuse and neglect to delinquency; (d) to violent behavior, and (e) to aggressive behavior in infants and young children; (f) abuse, withdrawal, and self-destructive behavior; and (g) studies of the impact of witnessing or observing violent behavior… (PsycINFO Database Record (c) 2010 APA, all rights reserved)