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Magda Osman

Publications and source records attributed to Magda Osman.

5 recordsLinked to original sources

The interaction between response effects during the acquisition of response priming.

In three experiments we investigated the role of associative learning in the acquisition of response priming by effect stimuli, by examining their interaction during response-effect learning. Having replicated the ability of visual effect stimuli to prime their associated responses, we paired a response with a compound consisting of visual and auditory effects before assessing the ability of the auditory effect stimulus to prime the response. This priming was reduced if the visual stimulus had been pre-trained as an effect of the response. By contrast, priming by the visual effect stimulus was potentiated when the auditory effect had been pre-trained. We interpret these interactions in terms of contemporary associative learning theory derived from studies of conditioning.

Adult↗

Action observation supports effector-dependent learning of finger movement sequences.

Practising a motor skill can result in effector-dependent learning (learning that does not transfer from the set of muscles used in training to a new set of muscles). Proceeding from neurophysiological evidence of motor activation during action observation, this study asked whether observational learning, learning through observation of skilled performance, can also be effector-dependent. Adult human participants observed a model's right hand as the model responded to an eight-item sequence in a serial reaction time (SRT) task. Their sequence learning was then compared in two tests with that of controls who had observed the model's right hand responding to random targets during training. All participants performed the SRT task with their right hand in the first test and with their left hand in the second. Evidence of observational learning was obtained in the right hand test but not in the left hand test. This implies that sequence learning based on observation of right hand performance did not transfer to the left hand, and therefore that observational learning can support effector-dependent learning of finger movement sequences. A second experiment used the same procedure to assess learning by a group of participants who observed a sequence of response locations only. This group did not observe the model's responses. Results suggested that action observation was necessary for the effector-dependent observational learning demonstrated in Experiment 1.

Adult↗

Individual differences in causal learning and decision making.

In judgment and decision making tasks, people tend to neglect the overall frequency of base-rates when they estimate the probability of an event; this is known as the base-rate fallacy. In causal learning, despite people's accuracy at judging causal strength according to one or other normative model (i.e., Power PC, DeltaP), they tend to misperceive base-rate information (e.g., the cause density effect). The present study investigates the relationship between causal learning and decision making by asking whether people weight base-rate information in the same way when estimating causal strength and when making judgments or inferences about the likelihood of an event. The results suggest that people differ according to the weight they place on base-rate information, but the way individuals do this is consistent across causal and decision making tasks. We interpret the results as reflecting a tendency to differentially weight base-rate information which generalizes to a variety of tasks. Additionally, this study provides evidence that causal learning and decision making share some component processes.

Cognition↗

Sequence learning by action, observation and action observation.

The serial reaction time (SRT) task was used to compare learning of a complex sequence by action (participants responded to sequential stimuli), by observation (participants watched but did not respond to sequential stimuli), and by action-observation (participants watched an expert model responding to sequential stimuli). Each of these groups was compared with an untrained control group. Experiment 1 indicated that both observation and action-observation were sufficient to support learning of a 12-item second-order conditional (SOC) sequence. Experiment 2 confirmed these findings, and showed that, as indexed by reaction time (RT), the extent of learning by observation and by action-observation was comparable to that of action-based learning. Using a recognition test, Experiment 2 and 3 also provided evidence that, whereas learning by stimulus observation was explicit, learning by action-observation was implicit. These findings are consistent with a connection between motor systems and implicit learning, but do not support the hypothesis that overt action is necessary for implicit learning.

Adult↗

An evaluation of dual-process theories of reasoning.

Current theories propose that reasoning comprises two underlying systems (Evans & Over, 1996; Sloman, 1996; Stanovich & West, 2000). The systems are identified as having functionally distinct roles, differ according to the type of information encoded, vary according to the level of expressible knowledge, and result in different responses. This article evaluates the arguments and the evidence from a select number of key tasks that have been supportive of dual-reasoning theorists' proposals. The review contrasts the dualist approach with a single-system framework that conjectures that different types of reasoning arise through the graded properties of the representations that are utilized while reasoning, and the different functional roles that consciousness has in cognition. The article concludes by arguing in favor of the alternative framework, which attempts to unify thedifferent forms of reasoning identified by dual-process theorists under a single system.

Humans↗