Letter perception: from pixels to pandemonium

In 1959, Oliver Selfridge proposed a model of letter perception, the Pandemonium model, in which the central hypothesis was that letters are identified via their component features. Although a consensus developed around this general approach over the years, key evidence in its favor remained lacking. Recent research has started to provide important evidence in favor of feature-based letter perception, describing the nature of the features, and the time-course of processes involved in mapping features onto abstract letter identities. There is now hope that future 'pandemonium-like' models will be able to account for the rich empirical database on letter identification that has accumulated over the past 50 years, hence solving one key component of the reading process.     

The role of adventitious reinforcement during differential reinforcement of other behavior: A systematic replication

Differential reinforcement of other behavior (DRO) is commonly used to decrease problem behavior by presenting reinforcers contingent upon the absence of a target response. Although it is well demonstrated that DROs decrease response rates, the processes producing these decreases are not well understood. The present study systematically replicated previous research assessing whether adventitious reinforcement of alternative behavior contributes to the effectiveness of DRO. We presented university students with two options on a computer and reinforced target responding on a variable-ratio schedule. Next, we compared decreases in target-response rates and any increases in alternative responding during DRO schedules versus yoked variable-time schedules or extinction probes. DRO schedules resulted in the lowest target-response rate and highest alternative-response rate. These findings generally provide some support for the adventitious reinforcement of “other” behavior.     

The effects of response effort on safe performance by therapists at an autism treatment facility

The effects of response effort on safe behaviors (i.e., glove wearing, hand sanitizing, and electrical outlet replacement) exhibited by therapists at an autism treatment center were examined. Participants were exposed to 2 or 3 levels of effort (i.e., high, medium, low) for each dependent variable. Results showed increased safe performance during the low-effort conditions relative to other conditions across all dependent variables for all participants.     

Problems with Dreyfus' dialectic

Phenomenology and the Cognitive Sciences -     

Haptic modality takes its time: Dynamic of activations of sensory modalities in perceptual and memory processes

Based on claims resulting from grounded cognition theory that perceptual and memory processes are using the same distributed systems, the present study investigated the temporal aspect of access to memory traces through haptic and auditory modalities. Unlike in the case of visual or auditory components, the perception of a vibrotactile component is more sequential in nature and therefore cannot be fully processed before the end of the signal. The present study explores the dynamic of components activation in a situation of audio‐vibrotactile asynchrony. We used a short‐term priming paradigm consisting of an association phase (between a vibration and sound) and a test phase testing priming effect of a vibrotactile stimulation on the processing of a target sound. Results showed an interference with a simultaneous processing and a facilitation with a sequential processing. The temporality process of perceptual components is also important at a memory level.     

The Temporal Dynamics of Regularity Extraction in Non‐Human Primates

Extracting the regularities of our environment is one of our core cognitive abilities. To study the fine‐grained dynamics of the extraction of embedded regularities, a method combining the advantages of the artificial language paradigm (Saffran, Aslin, & Newport, 1996 ) and the serial response time task (Nissen & Bullemer, 1987 ) was used with a group of Guinea baboons (Papio papio) in a new automatic experimental device (Fagot & Bonté, 2010 ). After a series of random trials, monkeys were exposed to language‐like patterns. We found that the extraction of embedded patterns positioned at the end of larger patterns was faster than the extraction of initial embedded patterns. This result suggests that there is a learning advantage for the final element of a sequence that benefits from the contextual information provided by previous elements.     

Adventitious reinforcement during long-duration DRO exposure

Differential reinforcement of other behavior (DRO) is a procedure often used to decrease problem behavior, but the processes responsible for behavior reduction are not well understood. This study assessed whether adventitious reinforcement of other behavior contributes to DRO effectiveness when, relative to previous research, DRO exposure is prolonged. Two response options were presented on a computer and target responding was reinforced on a variable-ratio schedule. Response rates were then compared during DRO versus yoked variable-time or extinction probes. Across 2 experiments, DRO decreased target responding and increased other responding more than control conditions. However, increases in other responding did not usually maintain despite target responding remaining at low levels. DRO might adventitiously reinforce other responses transiently but the decreases in target behavior could not be entirely explained by adventitious reinforcement of the other response. Instead, reductions in target responding likely depend on the discriminability of the DRO contingency.     

Community-based Peer Groups: an Intervention Programme for Teenage Mothers

This paper assesses the use of community-based peer groups as an intervention strategy to provide teenage mothers with an opportunity to share common experiences, receive social support and identify links between personal and social problems. The method utilized in a recent community project on teenage pregnancy is outlined. Over a period of 8 weeks a group of 10 teenage mothers met weekly to share their experiences of pregnancy and motherhood. The facilitators used various games and audio-visual aids to build rapport and to enhance willingness to discuss sensitive topics. The final session comprised a 1-day training workshop to enable the participants to act as co-facilitators for similar groups in the future. The evaluation indicated that the participants felt empowered by the opportunity to discuss common experiences and to have their perceptions affirmed by their peers. The potential value of this programme within the broader mental health context of South Africa is briefly discussed, and also the possibility of adding a consciousness-raising element to such groups.     

Simulating individual word identification thresholds and errors in the fragmentation task

This article presents a large-scale study that collected word identification thresholds and errors in the fragmentation task for all four-letter French words. In the first part of this article, we identify some of the variables (e.g., word frequency, neighborhood size, letter confusability) that affect performance in the fragmentation task. In the second part, we analyze individual response performance and identify different response strategies. We demonstrate that the interactive activation model can account for individual response strategies by adapting two of its original parameters: word-letter feedback and letter-word inhibition. In the third part, we demonstrate that the adaptation of the interactive activation model to the fragmentation task makes it possible to successfully simulate a facilitatory frequency effect on identification thresholds, an inhibitory neighborhood size effect on error rates, and an inhibitory letter confusability effect on identification thresholds. When the task-specific processes of the fragmentation task are specified and individual response strategies are considered, the interactive activation model provides a parsimonious architecture for modeling the task-independent processes involved in word perception.