Contextual conditioning

Eastern and Western interpretations of contextual control of phasic conditional responses (transswitching) are contrasted. The Eastern (Asratyan, 1965) approach emphasizes the role of the tonic conditional stimulus and the (hypothetical) tonic response it evokes. The Western (Lachnit, 1986) approach emphasizes the role of compound conditional stimuli. Although Lachnit showed that transswitching-like results can be obtained without a tonic stimulus, attempts to simulate transswitching experiments using a computer model of the Rescorla-Wagner theory (Kimmel and Lachnit, 1988) have shown that predictions from the theory approximate empirical results in human classical conditioning only when the tonic stimulus is given far greater weight than the phasic stimulus. In other words, only when the Rescorla-Wagner theory is made more like Asratyan’s theory, can the compound conditional stimulus approach account for real empirical transswitching data.     

A STELLA-II teaching simulation of the dynamics of action model

Although the Atkinson and Birch (1970) dynamics of action model of behavior is included in many textbooks, the details of the model are left out. To facilitate the teaching of the full theory, the conceptual model is outlined, research findings are reviewed, and a simulation model using STELLA-II is presented. STELLA-II, an icon-based program, provides a visual representation of the model that students can follow, with graphical and tabular output and animation of the rise and fall of parameter values.     

Transswitching and contextual conditioning

An empirical evaluation of temporal aspects of contextual conditioning was conducted in relation to Asratyan’s (1965) theory of transswitching and to an alternative explanation that was partly stimulated by the Rescorla-Wagner model (Rescorla and Wagner 1972). On the basis of a human electrodermal conditioning preparation suggested by Kimmel and Ray (1978), five groups with 12 subjects each were run. The results indicated that the basic phenomena of transswitching are robust and therefore could be replicated; but the Asratyan theory was rejected. All the results supported an alternative explanation: in contextual conditioning, duration of contextual stimuli is less important than order. Phasic switching is due to simultaneous occurrence of stimuli (differential compound conditioning) and is therefore compatible with the Rescorla-Wagner model. Tonic switching is due to signals that occur before a marked sequence of conditioning trials, in part a challenge to the Rescorla-Wagner model. Long delays between critical events can perhaps be compensated for by mediating memory processes.     

Cerebellar Substrates for Error Correction in Motor Conditioning

The authors evaluate a mapping of Rescorla and Wagner's (1972) behavioral model of classical conditioning onto the cerebellar substrates for motor reflex learning and illustrate how the limitations of the Rescorla-Wagner model are just as useful as its successes for guiding the development of new psychobiological theories of learning. They postulate that the inhibitory pathway that returns conditioned response information from the cerebellar interpositus nucleus back to the inferior olive is the neural basis for the error correction learning proposed by Rescorla and Wagner (Gluck, Myers, & Thompson, 1994; Thompson, 1986). The authors' cerebellar model expects that behavioral processes described by the Rescorla-Wagner model will be localized within the cerebellum and related brain stem structures, whereas behavioral processes beyond the scope of the Rescorla-Wagner model will depend on extracerebellar structures such as the hippocampus and related cortical regions. Simulations presented here support both implications. Several novel implications of the authors' cerebellar error-correcting model are described including a recent empirical study by Kim, Krupa, and Thompson (1998), who verified that suppressing the putative error correction pathway should interfere with the Kamin (1969) blocking effect, a behavioral manifestation of error correction learning. The authors also discuss the model's implications for understanding the limits of cerebellar contributions to associative learning and how this informs our understanding of hippocampal function in conditioning. This leads to a more integrative view of the neural substrates of conditioning in which the authors' real-time circuit-level model of the cerebellum can be viewed as a generalization of the long-term memory module of Gluck and Myers' (1993) trial-level theory of cerebellar-hippocampal interaction in motor conditioning.     

Equilibria of the Rescorla-Wagner model

The Rescorla-Wagner model has been a leading theory of animal causal induction for nearly 30 years, and human causal induction for the past 15 years. Recent theories (especially Psychol. Rev. 104 (1997) 367) have provided alternative explanations of how people draw causal conclusions from covariational data. However, theoretical attempts to compare the Rescorla-Wagner model with more recent models have been hampered by the fact that the Rescorla-Wagner model is an algorithmic theory, while the more recent theories are all computational. This paper provides a detailed derivation of the long-run behavior of the Rescorla-Wagner model under a wide range of parameters and experimental setups, so that the model can be compared with computational theories. It also shows that the model agrees with competing theories on a wider range of cases than had previously been thought. The paper concludes by showing how recently suggested modifications of the Rescorla-Wagner model impact the long-run behavior of the model.     

L’entraînement de la mémoire de travail par le programme Cogmed et le TDAH

IntroductionAttention-deficit/hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder. Inattention, hyperactivity, and impulsivity are key symptoms of ADHD. It is typically associated with working memory deficits at the cognitive level. For this reason, interventions have been designed to train working memory in ADHD. Currently, Cogmed Working Memory Training program is the most commonly used and studied program in clinical practice and research. This program is proposed as an intervention for ADHD that targets working memory deficits with specific exercises through intensive training sessions.ObjectivesThe goal of this literature review is to examine the effects of the Cogmed program in children and adolescents with ADHD on working memory, inhibition, non-verbal reasoning, attention functioning, ADHD symptoms and academic achievement. All existing studies on the subject that included a control group (n = 8) are reviewed.ResultsIt is clear from most studies that Cogmed training program increases and verbal and visuospatial working memory (or the phonological loop and visuospatial sketchpad in Baddeley's model (1986, 2007), among ADHD participants. However, transfer of learning is not demonstrated on other components of working memory that are not directly targeted by the program such as the central executive described in Baddeley's model or the secondary memory defined by Unsworth & Engle (2007). With regards to far transfer measures, results are controversial for inhibition, non-verbal reasoning, ADHD symptoms reported by parents, and reading abilities. No improvement is demonstrated for attentional capacities, ADHD symptoms reported by teachers and mathematic reasoning.ConclusionCogmed training improves verbal and visuospatial working memory, two cognitive functions that play an important role in ADHD. However, Cogmed's exercises need to be modified in order to train more complex working memory components such as the central executive (Baddeley, 1986, 2007) and the secondary memory (Unsworth & Engle, 2007), which are more impaired in ADHD than the phonological loop and visuospatial sketchpad. Another approach would be to design programs that can tackle a larger range of cognitive functions that are impaired in ADHD (e.g., inhibition). In future, studies evaluating such modified programs, direct observation instruments that are more sensitive to short-term changes need to be included. Follow-up measures should also be systematically included.     

A theoretical and empirical comparison of mainframe,microcomputer, and pocket calculator pseudorandom number generators

This article presents an extensive theoretical and empirical analysis of the pseudorandom number generators provided by subroutine libraries (NAG, CERN, IMSL, and ESSL), statistical and simulation software packages (GLIM, SAS, SPSS, DATASIM, ESSP, and LLRANDOMII), builtin functions of programming languages (APL, Turbo Pascal, Advanced BASIC, GW-BASIC, and QBASIC), and autoimplemented algorithms (Fishman & Moore, 1986; Wichmann & Hill, 1982; Van Es, Gill, & Van Putten, 1983). On the basis of these analyses, it is concluded that most of the built-in functions of the software packages that were tested can be used safely. In addition, it is concluded that the Wichmann and Hill algorithm is a good choice if only single-precision arithmetic is available, but that a prime-modulus multiplicative congruential generator with modulus 2³¹ ?1 and multiplier 16,807 is a better choice if double-precision arithmetic is available, and that the same generator with multiplier 62,089,911 or 742,938,285 is the best choice if extended-precision arithmetic is available. A Turbo Pascal and a VS FORTRAN program for the latter are given in the Appendixes.     

The role of cognition and coping in health behavior outcomes of asthmatic patients

This study investigates the meaning of cognitions and coping in well-being, hospital admissions, medication consumption, and absence from work due to asthma in asthmatic patients. Patients completed five questionnaires: the Respiratory Illness Opinion Survey (Kinsman, Jones, Matus, & Schum, 1976), measuring external control, psychological stigma, and optimism; the Asthma Coping Questionnaire (Maes, Schl?sser, & Vromans, 1986), measuring coping mechanisms; the Dutch version of the STAI (van der Ploeg, Defares, & Spielberger, 1979), measuring state and trait anxiety; the Questionnaire for Inner Well-Being (Hermans & Tak-van de Ven, 1973), measuring well-being; and the General Questionnaire for Asthmatic Patients (Maes et al., 1986) measuring medical outcome. Stepwise multiple regression showed that cognitions and coping determined a considerable part of the variance in the dependent variables: well-being, hospital admissions, and absence from work due to asthma.     

Is the number of trials a primary determinant of conditioned responding?

Acquisition of conditioned responding is thought to be determined by the number of pairings of a conditioned stimulus (CS) and an unconditioned stimulus (US). However, it is possible that acquisition is primarily determined not by the number of trials but rather by quantities that often correlate with the number of trials, such as cumulative intertrial interval (ITI) and the number of sessions. Four experiments examined whether the number of trials has an effect on acquisition of conditioned responding, once cumulative ITI and number of sessions are equated. Results of the experiments with rats and mice favor the hypothesis that over an eightfold range, variation in number of CS-US pairings has little effect. It is suggested that learning curves might more accurately be plotted across cumulative ITI or number of sessions, and not across number of trials. Results pose a challenge to trial-centered accounts of conditioning, as demonstrated by simulations of the Rescorla-Wagner model, a simplified version of Wagner's standard operating procedure model (SOP), and Stout & Miller's sometimes competing retrieval model (SOCR). A time-centered account, rate estimation theory (RET), predicts the main finding but has trouble with other aspects of the learning process more easily accommodated by trial-centered models.     

The widespread influence of the Rescorla-Wagner model

The theory of Pavlovian conditioning presented by Robert Rescorla and Allan Wagner in 1972 (the Rescorla-Wagner model) has been enormously important in animal learning research. It also has been applied in a variety of areas other than animal learning. We summarize the contribution of the Rescorla-Wagner model to research in verbal learning, social psychology, human category learning, human judgments of correlational relationships, transitive inference, color aftereffects, and physiological regulation. We conclude that there have been few models in experimental psychology as influential as the Rescorla-Wagner model.     

Making causal judgments from the proportion of confirming instances: the pCI rule

It is proposed that causal judgments about contingency information are derived from the proportion of confirmatory instances (pCI) that are evaluated as confirmatory for the causal candidate. In 6 experiments, pCI values were manipulated independently of objective contingencies assessed by the deltaP rule. Significant effects of the pCI manipulations were found in all cases, but causal judgments did not vary significantly with objective contingencies when pCI was held constant. The experiments used a variety of stimulus presentation procedures and different dependent measures. The power PC theory, a weighted version of the deltaP rule, the Rescorla-Wagner associative learning model (R. A. Rescorla & A. R Wagner, 1972), and the deltaD rule, which is the frequency-based version of the pCI rule, were unable to account for the significant effects of the pCI manipulations. These results are consistent with a general explanatory approach to causal judgment involving the evaluation of evidence and updating of beliefs with regard to causal hypotheses.     

Learning about environmental geometry: an associative model

K. Cheng (1986) suggested that learning the geometry of enclosing surfaces takes place in a geometric module blind to other spatial information. Failures to find blocking or overshadowing of geometry learning by features near a goal seem consistent with this view. The authors present an operant model in which learning spatial features competes with geometry learning, as in the Rescorla-Wagner model. Relative total associative strength of cues at a location determines choice of that location and thus the frequencies of reward paired with each cue. The model shows how competitive learning of local features and geometry can appear to result in potentiation, blocking, or independence, depending on enclosure shape and kind of features. The model reproduces numerous findings from dry arenas and water mazes.     

Conditioning,attention, and the CS-US interval

A revised version of the Rescorla-Wagner (1972) mathematical model is presented. A metatheoretical assumption of an attentional process, the added revision, is conceived as an independent α-salience growth factor determining both rate of association and performance. Conditioned stimulus-unconditioned stimulus (CS-US) correlation, and CS-US interval (two primary conditioning parameters) are incorporated in the mathematical model as α-salience growth rate and as α-salience and association asymptote factors, respectively. In this manner, the long-standing issue of necessary and sufficient factors in classical conditioning is resolved. An empirical assessment of the model’s parameters has been included.     

The importance of feature distribution and correlation for simulating 3 to 4-month-old infants' visual categorization processes

Mareschal, French, and Quinn (2000) and Mareschal, Quinn, and French (2002) have proposed a connectionist model of visual categorization in 3- to 4-month-old infants that simulates and predicts previously unexplained behavioural effects such as the asymmetric categorization effect (French, Mareschal, Mermillod, & Quinn, 2004). In the current paper, we show that the model's ability to simulate the asymmetry depends on the correlational structure of the stimuli. These results are important given that adults (Anderson & Fincham, 1996) as well as infants (Younger & Cohen, 1986) are able to rely on correlation information to perform visual categorization. At a behavioural level, the current paper suggests that pure bottom-up processes, based on the correlational structure of the categories, could explain the disappearance of the asymmetry in older 10-month-old infants (Furrer & Younger, 2005). Moreover, our results also raise new challenges for visual categorization models that attempt to simulate the shift from asymmetric categorization in 3- to 4-month-old to symmetric categorization in 10-month-old infants (Shultz & Cohen, 2004; Westermann & Mareschal, 2004, 2012).     

The role of memory for compounds in cue competition

Revisions of common associative learning models incorporate a within-compound association mechanism in order to explain retrospective cue competition effects (e.g., [Dickinson, A., & Burke, J. (1996). Within-compound associations mediate the retrospective revaluation of causality judgements. Quarterly Journal of Experimental Psychology, 49B, pp. 60-80.]). These models predict a correlation between memory for compounds (as a measure for the strength of within-compound associations) and retrospective cue competition but not forward cue competition. This was indeed found in a study of [Melchers, K. G., Lachnit, H., & Shanks, D. (2004). Within-compound associations in retrospective revaluation and in direct learning: A challenge for comparator theory. Quarterly Journal of Experimental Psychology, 57B, pp. 25-54.]. We argue that a higher-order reasoning account of causal learning can also explain the evidence for the role of within-compound associations in cue competition. Moreover, this account predicts that if making inferences during the learning stage is impeded, a correlation between memory for compounds and forward cue competition should be found as well. The results of a new study confirmed this prediction.     

A criterion-shift model for enhanced discriminability in perceptual identification: A note on the counter model

The original version of the counter model for perceptual identification (Ratcliff & McKoon, 1997) assumed that word frequency and prior study act solely to bias the identification process (i.e., subjects have a tendency to prefer high-frequency and studied low-frequency words, irrespective of the presented word). In a recent study, using a two-alternative forced-choice paradigm, we showed an enhanced discriminability effect for high-frequency and studied low-frequency words (Wagenmakers, Zeelenberg, & Raaijmakers, 2000). These results have led to a fundamental modification of the counter model: Prior study and high frequency not only result in bias, but presumably also result in a higher rate of feature extraction (i.e., better perception). We demonstrate that a criterion-shift model, assuming limited perceptual information extracted from the flash as well as a reduced distance to an identification threshold for high-frequency and studied low-frequency words, can also account for enhanced discriminability.     

More evidence for the universality of a contempt expression

Since its publication in 1986, Ekman and Friesen's (1986) discovery of a universal facial expression unique to contempt has received considerable attention (e.g., see Ekman & Friesen, 1988; Ekman & Heider, 1988; Ekman, O'Sullivan, & Matsumoto, 1991a, 1991b; Izard & Haynes, 1988; Russell, 1991a, 1991b; Ricci Bitti, Brighetti, Garotti, Boggi-Cavallo, 1989). Actually, much of this argument began before there was adequate sampling of contempt photographs across many cultures. In order to address this concern, this study reports judgment data on all 12 photos used in previous studies depicting the contempt expression from four non-American cultures. The data provide a strong replication of Ekman and Friesen's (1986) and Ekman and Heider's (1988) findings for a universal expression of contempt.The research reported in this article was supported in part by a grant from the National Institute of Mental Health (MH 42749-01), and by a Faculty Award for Creativity, Scholarship, and Research from San Francisco State University. I would like to thank Veronica Ton for her aid in the collection of the Vietnamese data; Valerie Hearn for her aid in the collection of the Polish and Hungarian data; Masami Kobayashi, Fazilet Kasri, Deborah Krupp, Bill Roberts, and Michelle Weissman for their aid in my research program on emotion; and William Irwin for his aid in the data analysis.     

The dynamics of Prägnanz

Summary There is quite wide-spread agreement about the relevance of pattern Pragnanz (Koffka, 1935) with respect to the human interpretation of visual patterns. There is less agreement about whether pattern Pragnanz is based solely on pattern information (static) or also on the history of the perceiver (dynamic). In Van Leeuwen and Van den Hof (1991), experimental data concerning serial patterns are presented within the framework of the dynamic-network approach initiated by Buffart (1986, 1987). These experimental data are claimed to give evidence against the static-coding approach initiated by Leeuwenberg (1969, 1971). In the present paper, however, I show first that Buffart's theoretical basis is incorrect, and that in fact Leeuwenberg's static-coding approach is the basis for the dynamic-network approach. Second, I show that those experimental data rather give evidence in favor of the static-coding approach, by using those same data for a test of the most recent static-coding model (Van der Helm & Leeuwenberg, 1991; Van der Helm, Van Lier, & Leeuwenberg, 1992). Finally, I propose a reconciliation between the two approaches, in the sense that the dynamic-network model could be shaped in such a way that it yields a simulation, and maybe even an enrichment, of the static-coding model.     

A computational model for simulating text comprehension

In the present article, we outline the architecture of a computer program for simulating the process by which humans comprehend texts. The program is based on psycholinguistic theories about human memory and text comprehension processes, such as the construction-integration model (Kintsch, 1998), the latent semantic analysis theory of knowledge representation (Landauer & Dumais, 1997), and the predication algorithms (Kintsch, 2001; Lemaire & Bianco, 2003), and it is intended to help psycholinguists investigate the way humans comprehend texts.