Ginesa López-Crespo

Enhancing recognition memory in adults through differential outcomes

It has been widely demonstrated that the differential outcomes procedure (DOP) facilitates both the learning of conditional relationships and the memory for the conditional stimuli in animal subjects. For conditional discriminations in humans, the DOP also produces an increase in the speed of acquisition and/or final accuracy. However, the potential facilitative effects of differential outcomes in human memory have not been fully assessed. In the present study, we aimed to test whether this procedure improves performance on a recognition memory task in healthy adults. Participants showed significantly better delayed face recognition when differential outcomes were used. This novel finding is discussed in the light of other studies on the differential outcomes effect (DOE) in both animals and humans, and implications for future research are presented.

Improving Delayed Face Recognition in Alzheimer's Disease by Differential Outcomes

OBJECTIVE Previous studies have demonstrated the benefit of the differential outcomes procedure (DOP) in human learning. In the present study we aimed to explore whether the DOP might also help to overcome the face recognition memory deficit commonly observed in Alzheimers disease (AD) patients. METHOD A delayed matching-to-sample task was used. Participants were instructed to choose which of the 4 alternative faces (comparison stimuli) matched the previously seen face (sample stimulus). Either short (5 seconds) or long (25 seconds) delays were interposed between the sample and the comparison stimuli. In the differential outcomes condition each sample face was paired with its own outcome. In contrast, in the nondifferential condition, outcomes were randomly arranged. RESULTS The differential outcomes effect (DOE) was evident in the AD patients with both accuracy and latency data. That is, they showed a significantly better and faster delayed face recognition when differential outcomes were arranged. The analyses also revealed a significant main effect of delay; participants were slower in the 25 seconds condition than in the 5 seconds condition, but the difference was higher in the patients than in the controls. CONCLUSIONS These findings demonstrate, to our knowledge for the first time, that face recognition memory in patients with Alzheimer is improved when differential outcomes are used and draw attention to the potential of this procedure as a therapeutic technique.

Visual working memory in deaf children with diverse communication modes: Improvement by differential outcomes

Although visual functions have been proposed to be enhanced in deaf individuals, empirical studies have not yet established clear evidence on this issue. The present study aimed to determine whether deaf children with diverse communication modes had superior visual memory and whether their performance was improved by the use of differential outcomes. Severely or profoundly deaf children who employed spoken Spanish, Spanish Sign Language (SSL), and both spoken Spanish and SSL modes of communication were tested in a delayed matching-to-sample task for visual working memory assessment. Hearing controls were used to compare performance. Participants were tested in two conditions, differential outcome and non-differential outcome conditions. Deaf groups with either oral or SSL modes of communication completed the task with less accuracy than bilingual and control hearing children. In addition, the performances of all groups improved through the use of differential outcomes.

Differential outcomes training improves face recognition memory in children and in adults with Down syndrome

Previous studies have demonstrated that the differential outcomes procedure (DOP), which involves paring a unique reward with a specific stimulus, enhances discriminative learning and memory performance in several populations. The present study aimed to further investigate whether this procedure would improve face recognition memory in 5- and 7-year-old children (Experiment 1) and adults with Down syndrome (Experiment 2). In a delayed matching-to-sample task, participants had to select the previously shown face (sample stimulus) among six alternatives faces (comparison stimuli) in four different delays (1, 5, 10, or 15s). Participants were tested in two conditions: differential, where each sample stimulus was paired with a specific outcome; and non-differential outcomes, where reinforcers were administered randomly. The results showed a significantly better face recognition in the differential outcomes condition relative to the non-differential in both experiments. Implications for memory training programs and future research are discussed.

Differential outcomes aid the formation of categorical relationships between stimuli.

The differential outcome effect is when learning is enhanced through the application of different outcomes to different conditions of a task. Here we explore whether one difference in learning with differential outcomes is an enhanced categorisation of objects. We demonstrate that participants learning conditional discriminations are better able to identify previously unpaired objects as belonging to the same category when differential outcomes were used in learning these stimuli.

An Architecture Proposal for Adaptive Neuropsychological Assessment

In this work we present the architecture of an special sort of software capable of changing its presentation depending on the behavior of a particular user. Although the proposed solution is applicable as the base of a general adaptive application, we want to expose the peculiarities of the model designed specifically to work in a special domain, the cognitive neuropsychology. In this domain, one of the most important topic is the design of task for the assessment of patients with cerebral damage. Depending of the patient, and its particular characteristics, the therapists must adjust the exposition time of several stimulus in order to obtain the best parameter values, and therefore to obtain the profile in a precise way. This is a very important topic because correct assessment implies successful rehabilitation but, in practice, this process is time-consuming and difficult to be done. So, with the aim to help the therapists in the task tuning process, we propose the use of artificial intelligence-based techniques in order to detect the patients profile automatically during the execution time, adapting the values of the parameters dynamically. In particular, we propose the foundation of temporal similarities techniques as the basis of design adaptive software.