Does temporal contiguity moderate contingency learning in a speeded performance task?

In four experiments, we varied the time between the onset of distracting nonwords and target colour words in a word-word version of the colour-word contingency learning paradigm. Contingencies were created by pairing a distractor nonword more often with one target colour word than with other colour words. A contingency effect corresponds to faster responses to the target colour word on high-contingency trials (i.e., distractor nonword followed by the target colour word with which it appears most often) than on low-contingency trials (i.e., distractor nonword followed by a target colour word with which it appears only occasionally). Roughly equivalent-sized contingency effects were found at stimulus-onset asynchronies (SOAs) of 50, 250, and 450?ms in Experiment 1, and 50, 500, and 1,000?ms in Experiment 2. In Experiment 3, a contingency effect was observed at SOAs of -50, -200, and -350?ms. In Experiment 4, interstimulus interval (ISI) was varied along with SOA, and learning was equivalent for 200-, 700-, and 1,200-ms SOAs. Together, these experiments suggest that the distracting stimulus does not need to be presented in close temporal contiguity with the response to induce learning. Relations to past research on causal judgement and implications for further contingency learning research are discussed.     

Does temporal contiguity moderate contingency learning in a speeded performance task?

In four experiments, we varied the time between the onset of distracting nonwords and target colour words in a word–word version of the colour–word contingency learning paradigm. Contingencies were created by pairing a distractor nonword more often with one target colour word than with other colour words. A contingency effect corresponds to faster responses to the target colour word on high-contingency trials (i.e., distractor nonword followed by the target colour word with which it appears most often) than on low-contingency trials (i.e., distractor nonword followed by a target colour word with which it appears only occasionally). Roughly equivalent-sized contingency effects were found at stimulus-onset asynchronies (SOAs) of 50, 250, and 450 ms in Experiment 1, and 50, 500, and 1,000 ms in Experiment 2. In Experiment 3, a contingency effect was observed at SOAs of –50, –200, and –350 ms. In Experiment 4, interstimulus interval (ISI) was varied along with SOA, and learning was equivalent for 200-, 700-, and 1,200-ms SOAs. Together, these experiments suggest that the distracting stimulus does not need to be presented in close temporal contiguity with the response to induce learning. Relations to past research on causal judgement and implications for further contingency learning research are discussed.     

Does working memory training have to be adaptive?

This study tested the common assumption that, to be most effective, working memory (WM) training should be adaptive (i.e., task difficulty is adjusted to individual performance). Indirect evidence for this assumption stems from studies comparing adaptive training to a condition in which tasks are practiced on the easiest level of difficulty only [cf. Klingberg (Trends Cogn Sci 14:317–324, 2010)], thereby, however, confounding adaptivity and exposure to varying task difficulty. For a more direct test of this hypothesis, we randomly assigned 130 young adults to one of the three WM training procedures (adaptive, randomized, or self-selected change in training task difficulty) or to an active control group. Despite large performance increases in the trained WM tasks, we observed neither transfer to untrained structurally dissimilar WM tasks nor far transfer to reasoning. Surprisingly, neither training nor transfer effects were modulated by training procedure, indicating that exposure to varying levels of task difficulty is sufficient for inducing training gains.     

Does luck have a place in epistemology?

Some epistemologists hold that exploration and elaboration of the nature of luck will allow us to better understand knowledge. I argue this is a mistake.     

Does learning to count involve a semantic induction?

We tested the hypothesis that, when children learn to correctly count sets, they make a semantic induction about the meanings of their number words. We tested the logical understanding of number words in 84 children that were classified as "cardinal-principle knowers" by the criteria set forth by Wynn (1992). Results show that these children often do not know (1) which of two numbers in their count list denotes a greater quantity, and (2) that the difference between successive numbers in their count list is 1. Among counters, these abilities are predicted by the highest number to which they can count and their ability to estimate set sizes. Also, children's knowledge of the principles appears to be initially item-specific rather than general to all number words, and is most robust for very small numbers (e.g., 5) compared to larger numbers (e.g., 25), even among children who can count much higher (e.g., above 30). In light of these findings, we conclude that there is little evidence to support the hypothesis that becoming a cardinal-principle knower involves a semantic induction over all items in a child's count list.     

Why is learning to read a hard task for some children?

In this brief review of some of my research on reading disability, I argue that a child’s development into literacy has two major ontogenetic roots, one involving early informal literacy socialization and one related to phonological awareness. Although failure in reading acquisition might be a question of cultural deprivation, the dynamic interaction between genetic dispositions and environment must be acknowledged, especially in a society providing rich sources of print exposure. The crucial transition in literacy development involves a step from implicit to explicit control of the phonemic units of language. When the cipher of the alphabetic system is understood the child is equipped with a powerful instrument for self teaching. A primary source of reading disability is then related to problems of segmenting the speech stream into phonemic units. The poor functioning of the phonological module seems to be a circumscribed deficit not related to general cognitive ability. The causal and reciprocal relationship between phonological awareness and learning to read has been demonstrated in my research over 20 years. Some of these studies are briefly reviewed in this article. The preventive and remedial implications of the findings are rather obvious.     

Does handedness determine which hand leads in a bimanual task?

Right- and left-handers (n = 16 in each group) were tested on a bimanual circle task that required drawing either in the same direction (parallel) or in a mirror symmetrical coordination mode with the two hands. The authors' primary purposes were to examine the effect of circle direction on within-hand and between-hands variables and to determine whether the relation between hand lead and coordination mode (parallel or mirror symmetrical) differs for left- and right-handers. A strong relation was found between lead hand and movement condition, which depended on the direction of the movements and whether the task was parallel or mirror symmetrical. The pattern of results was similar for left- and right-handers on parallel tasks, but group differences were found with respect to mirror symmetrical tasks. At odds with the general claim that the dominant hand leads, the present results indicated that hand dominance does not generally determine which hand leads.     

Young children's affective decision-making in a gambling task: Does difficulty in learning the gain/loss schedule matter?

This research investigated the development of affective decision-making (ADM) during early childhood, in particular role of difficulty in learning a gain/loss schedule. In Experiment 1, we administrated the Children's Gambling Task (CGT) to 60 Chinese children aged 3 and 4, replicating the results obtained by Kerr and Zelazo [Kerr, A., & Zelazo, P. D. (2004). Development of “hot” executive function: The Children's Gambling Task. Brain and Cognition, 55, 148–157]. In Experiment 2, the CGT was modified to make it easier for young children to learn the gain/loss schedule by increasing delayed loss frequency and magnitude in the disadvantageous deck, and a larger sample (181 children aged 3–5) was assessed. Age-differences between 3- and 4-year-olds, rather than 4- and 5-year-olds, showed that ADM develops rapidly between 3 and 4 years. The reduction of the difficulty in learning the gain/loss schedule provides the basis for an account of the development of young children's AMD.     

Can skilled readers perform a second task in parallel? A functional connectivity MRI study

When asked to search for a target letter while reading, the patterns with which people miss the target letter reveal information about the process of reading itself. Questions remain as to whether this paradigm reflects normal reading processes however. We used a novel continuous-performance neuroimaging paradigm to address this question. In separate scanning runs, subjects either read alone, read while searching for a target letter, or searched non-words continuously. Functional connectivity analysis recovered the full extent of brain areas identified for reading in a localizer scan, with no differences between reading alone and the dual task condition. Differences were found, however, between both reading conditions and the nonword search condition. These results demonstrate that in skilled readers brain activation associated with reading is unaffected by a concurrent letter-search task. They further demonstrate the utility of a naturalistic, continuous-performance paradigm for studying the neural basis of language processing.     

How well do elderly people cope with uncertainty in a learning task?

The relation between age, task complexity and learning performance in a Multiple Cue Probability Learning task was studied by systematically varying the level of uncertainty present in the task, keeping constant the direction of relationships. Four age groups were constituted: young adults (mean age = 21), middle-aged adults (45), elderly people (69) and very elderly people (81). Five uncertainty levels were considered: predictability = 0.96, 0.80, 0.64, 0.48, and 0.32. All relationships involved were direct ones. A strong effect of uncertainty on 'control', a measure of the subject's consistency with respect to a linear model, was found. This effect was essentially a linear one. To each decrement in predictability of the task corresponded an equal decrement in participants' level of control. This level of decrement was the same, regardless of the age of the participant. It can be concluded that elderly people cope with uncertainty in probability learning tasks as well as young adults.     

Does word training increase or decrease interference in a stroop task?

First and second graders (6- and 7-year-olds) practiced reading 20 words. Before and after word training, they named pictures printed with and without these words as distractors. Of interest was whether training would enhance or diminish the interference created by these words in the picture-naming task. Results indicated that children who learned to recognize unfamiliar distractor words more accurately suffered more interference after training. In contrast, children who were already familiar with the words and learned to recognize them faster experienced less interference following training. Results are interpreted as supporting LaBerge and Samuels' model of automatic word processing. Effects of accuracy training are attributed to the elimination of attention as a requirement for processing distractor words. Effects of speed training are attributed to a reduction in the time consumed by distractor words in the central processor.     

Does task sustainability provide a unified measure of subjective task difficulty?

Psychonomic Bulletin & Review - What accounts for the subjective difficulty of a task? It is easy to suggest ad hoc measures, such as how many individuals can do the task, how long it takes...     

Does reliabilism have a temporality problem?

Philosophical Studies - Matthew Frise claims that reliabilist theories of justification have a temporality problem—the problem of providing a principled account of the temporal parameters of...     

Do private gestures have a self-regulatory function? A case study

One of the most fascinating phenomena in early development is that babies not only understand signs others direct to them and later use them to communicate with others, but they also come to direct the same signs towards themselves in a private way. Private gestures become "tools of thought". There is a considerable literature about private language, but almost nothing about private gestures. Private gestures pose an intriguing communicative puzzle: they are communicative, but with the self. In this paper we study two types of private gestures (signs) before language: (1) private ostensive gestures and (2) private pointing gestures. We show in a case study of one child between 12 and 18 months of age that both are used with a self-reflexive function, as a way of "thinking" what to do, in order to solve a problem in the conventional use of an object. The private gestures become self-reflexive signs.     

Does social environment influence learning ability in a family-living lizard?

Early developmental environment can have profound effects on individual physiology, behaviour, and learning. In birds and mammals, social isolation during development is known to negatively affect learning ability; yet in other taxa, like reptiles, the effect of social isolation during development on learning ability is unknown. We investigated how social environment affects learning ability in the family-living tree skink (Egernia striolata). We hypothesized that early social environment shapes cognitive development in skinks and predicted that skinks raised in social isolation would have reduced learning ability compared to skinks raised socially. Offspring were separated at birth into two rearing treatments: (1) raised alone or (2) in a pair. After 1 year, we quantified spatial learning ability of skinks in these rearing treatments (N = 14 solitary, 14 social). We found no effect of rearing treatment on learning ability. The number of skinks to successfully learn the task, the number of trials taken to learn the task, the latency to perform the task, and the number of errors in each trial did not differ between isolated and socially reared skinks. Our results were unexpected, yet the facultative nature of this species’ social system may result in a reduced effect of social isolation on behaviour when compared to species with obligate sociality. Overall, our findings do not provide evidence that social environment affects development of spatial learning ability in this family-living lizard.     

Does retinal size have a unique correlate in perceived size?

Subjects estimated the size and distance of a single electroluminescent disc in the absence of distance cues and without the use of visual comparators. For different groups of Ss the disc subtended a visual angle of 1, 2, 4, or 8 deg. The size estimates varied directly with visual angle and the distance estimates varied inversely with visual angle. These results were considered in relation to the question of whether or not retinal size hasa direct correlate in perceived size.     

Is study time allocated selectively to a region of proximal learning?

Five experiments investigated whether people allocate their study time according to the discrepancy reduction model (i.e., to the most difficult items; J. Dunlosky & C. Hertzog, 1998) or to items in their own region of proximal learning. Consistent with the latter hypothesis, as more time was given, people shifted toward studying more difficult items. Experts, whether college students or Grade 6 children, devoted their time to items that were more difficult than did novices. However, in a multiple-trials experiment, people regressed toward easier items on Trial 2 rather than shifting to more difficult items, perhaps because Trial 1 feedback revealed poor learning of the easiest items. These findings are in opposition to the discrepancy reduction model and support the region of proximal learning hypothesis.