Discriminative learning and associative memory under the differential outcomes procedure is modulated by cognitive load.

Working memory (WM) has been thought to be the cause of associative memory deficits in older adults. Previous research has demonstrated the benefits of a discriminative learning procedure, the differential outcomes procedure (DOP), to ameliorate such associative-memory maintenance deficits in situations that simulate adherence to medical prescriptions in both healthy and pathological ageing. Specifically, the DOP involves rewarding each correct response to each stimulus-stimulus association with a distinct and unique outcome (reinforcer). The aim of the present study was to explore the limits of this procedure by testing the amount of cognitive load at which the DOP improves discriminative learning and associative memory in a task that simulates adherence to medical treatment in undergraduate students. During the training phase, participants were asked to learn three pill/name (low-load condition) or four pill/name associations (high-load conditions) under the DOP in comparison with a control condition (the non-differential outcomes condition, NOP). Long-term retention of such learned associations was tested 1h and 1week after completion of the training phase. Participants showed a better accuracy and long-term retention of the learned associations when the DOP was used, but just in the high-load condition. These results suggest that when WM is overtaxed, the DOP plays a fundamental role in the long-term maintenance of the learned stimulus-stimulus associations, rendering such learning procedure as a useful technique to enhance people's discriminative learning and associative memory.

Enhanced learning and retention of medical information in Alzheimer's disease after differential outcomes training.

BACKGROUND: Adherence to treatment is a crucial factor for patients who have chronic illnesses or multiple morbidities and polypharmacy, which is frequently found in older adults. The non-adherence to medications has important economic and social consequences as well as impacts on the health of the patients. One of the reasons that can explain the low adherence to treatment, is the memory deficits that are characteristics of this population and that are even more evident in cases that involve neurodegenerative diseases. METHODS AND FINDINGS: In this study, we explore whether the differential outcomes procedure (DOP), which has been shown to be useful in improving discriminative learning and memory in different populations, may facilitate learning and retention of medical recommendations in older adults who have been diagnosed with Alzheimer's disease. The results demonstrate that when this procedure was applied, the patients showed improvements in learning and long-term retention of two pill/time of day associations in a situation that simulates adherence to medical prescriptions. CONCLUSIONS: These findings contribute new data about the potential benefits of the DOP in patients with neurodegenerative disorders, highlighting the important role that this procedure could play in addressing important issues related to the health and quality of life of older adults, with or without neurodegenerative diseases, such as low adherence to medical treatments.

Learning and Recall of Medical Treatment-Related Information in Older Adults Using the Differential Outcomes Procedure.

It has recently been reported that the differential outcomes procedure (DOP) might be one of the therapeutical techniques focused at promoting autonomy in the elderly to deal with their medical issues. Molina et al. (2015) found that a group of healthy young adults improved their learning and long-term retention of six disorder/pill associations when each relationship to be learned was associated with a particular reinforcer (the differential outcomes condition) compared to when they were randomly administered (the non-differential outcomes condition). In the present study, we extend these findings to older adults who usually show difficulties to remember to take their medications as prescribed. Participants were asked to learn the association between three pills and the specific time at the day when they had to take each medication. Two memory tests were also performed 1 h and 1 week after completing the training phase. Results showed a faster learning of the task and long-term retention of the previously learned associations (pill/time of day) when differential outcomes were used. Furthermore, the older adults' performance in the learning and memory phases did not differ from that of the younger adults in the DOP condition. These findings demonstrate that this procedure can help elderly people to ameliorate not only their learning, but also their long-term memory difficulties, suggesting the potential for the DOP to promote adherence to treatment in this population.

Mejora del aprendizaje discriminativo en niños: consecuencias diferenciales y administración manual de diferentes formas de refuerzo / Improvement of discriminative learning in children: differential outcomes and manual administration of different types of reinforcement

Diversos estudios han mostrado que el aprendizaje discriminativo puede ser mejorado mediante la asignación de una consecuencia única para cada asociación que ha de ser aprendida (procedimiento de consecuencias diferenciales, PCD). El objetivo de este estudio fue comprobar si el PCD mejoraría el aprendizaje de discriminaciones simbólicas en niños de 5 y 7 años de edad, mediante una tarea de lápiz y papel en la que se usaron diferentes tipos de entrenamiento: 1) administración de reforzadores tras las respuestas correctas (+), 2) retirada de reforzadores tras los errores (-), o 3) una combinación de ambas (+/-). En los Experimentos 1a y 1b se utilizaron reforzadores primarios y secundarios, mientras que en los Experimentos 2a y 2b se utilizaron solo reforzadores primarios. Los participantes mostraron una mejor ejecución en las tareas cuando se administraron consecuencias diferenciales independientemente del tipo de reforzador (primario y secundario o sólo primario) y del tipo de entrenamiento empleado (+, -, o +/-). Estos resultados se suman a los encontrados en estudios previos (Martínez, Estévez, Fuentes y Overmier, 2009; Martínez, Flores, González Salinas, Fuentes y Estévez, 2013) demostrando, además, que el efecto beneficioso del PCD sobre el aprendizaje discriminativo es independiente del medio por el cual presentamos los estímulos y las consecuencias, lo que facilita su posible utilización en contextos aplicados

In recent years, several studies have demonstrated that discriminative learning is facilitated when each association to be learned is always followed by a unique outcome. This way of providing outcomes was called the differential outcomes procedure (DOP). The aim of the study reported here was to assess whether the DOP could improve learning of symbolic conditional discriminations in 5- and 7-year-old children when performing a paper-and-pencil task using different types of training in which: 1) reinforcers were given after correct choices (+), 2) reinforcers were withdrawn when errors were made (-), or 3) a combination of both (+/-). In Experiments 1a and 1b secondary reinforcers were used along with primary reinforcers, while in Experiments 2a and 2b only primary reinforcers were used. Participants showed better performance when differential outcomes were arranged regardless of the type of reinforcers (secondary plus primary or only primary) and the different strategies of reinforcement (+, -, or +/-). These results add to those found by Martínez et al. (2009, 2013) and demonstrate that the beneficial effect of the DOP on discriminative learning is also independent of the way in which the stimuli and the outcomes are presented, facilitating its use in applied contexts

The Differential Outcomes Procedure Enhances Adherence to Treatment: A Simulated Study with Healthy Adults.

Memory for medical recommendations is a prerequisite for good adherence to treatment, and therefore to ameliorate the negative effects of the disease, a problem that mainly affects people with memory deficits. We conducted a simulated study to test the utility of a procedure (the differential outcomes procedure, DOP) that may improve adherence to treatment by increasing the patient's learning and retention of medical recommendations regarding medication. The DOP requires the structure of a conditional discriminative learning task in which correct choice responses to specific stimulus-stimulus associations are reinforced with a particular reinforcer or outcome. In two experiments, participants had to learn and retain in their memory the pills that were associated with particular disorders. To assess whether the DOP improved long-term retention of the learned disorder/pill associations, participants were asked to perform two recognition memory tests, 1 h and 1 week after completing the learning phase. The results showed that compared with the standard non-differential outcomes procedure, the DOP produced better learning and long-term retention of the previously learned associations. These findings suggest that the DOP can be used as a useful complementary technique in intervention programs targeted at increasing adherence to clinical recommendations.

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.

El procedimiento de consecuencias diferenciales mejora el reconocimiento de rostros con independencia de su valencia emocional / The differential outcomes procedure improves face recognition irrespective of their emotional valence

En los últimos años, diversos estudios han demostrado que el procedimiento de consecuencias diferenciales (PCD) es una herramienta que mejora tanto el aprendizaje discriminativo como la memoria a corto plazo en diferentes poblaciones. Con respecto a esta última, los estudios realizados hasta el momento se centran, principalmente, en tareas de reconocimiento de caras neutras que no presentan ningún tipo de expresión facial emocional. En el presente estudio, nuestro objetivo fue explorar en jóvenes universitarios si el PCD mejoraría la ejecución de una tarea de memoria a corto plazo de reconocimiento de caras que presentan diferentes expresiones faciales emocionales en el momento de su reconocimiento. Los participantes mostraron un mejor reconocimiento demorado de caras cuando se administraron consecuencias diferenciales tras sus respuestas correctas. Estos resultados añaden nueva información acerca del funcionamiento del procedimiento y refuerzan la idea de que el PCD puede ser una herramienta útil en contextos más aplicados(AU)

In the last years, several studies have demonstrated that the differential outcomes procedure (DOP) facilitates both discriminative learning and short-term memory in different populations. It is worth to note that in most published studies exploring the usefulness of the DOP to improve memory, it has been used recognition memory tasks with neutral faces without emotional expressions. Our primary purpose in the present study was to test whether this procedure might increase performance of a facial recognition memory task when emotional facial expressions were used as comparison stimuli. Participants showed a significantly better delayed face recognition when differential outcomes were arranged. This novel finding adds information about how the DOP works and strongly suggests that this procedure can be a useful technique in applied contexts(AU)

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 Alzheimer's 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.

Minimizing sleep deprivation effects in healthy adults by differential outcomes.

Sleep deprivation reduces vigilance or arousal levels, affecting the efficiency of certain cognitive functions such as learning and memory. Here we assessed whether the differential outcomes procedure (DOP), a learning procedure that has proved useful to ameliorate episodic memory deficits, can also improve memory performance in sleep-deprived participants. Photographs were presented as sample faces. A probe face was then presented for recognition after either short or long delays. In the differential outcomes condition a unique reinforcer followed correct responses. In the non-differential outcomes condition reinforcers were provided in a random manner. The results indicated that the DOP prevented the recognition memory to decrement during the long delay in the control group, replicating previous findings. The sleep-deprived group showed DOP benefits mainly with the short delay, when working memory could be affected by low arousal. These findings confirm that the DOP can overcome impaired recognition memory due to sleep deprivation conditions.

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.

Improvement of age-related memory deficits by differential outcomes.

BACKGROUND: The differential outcomes procedure (DOP) has proved useful to improve discrimination learning in both animals and humans. Here we adapted DOP to assess its utility to overcome the memory loss commonly associated with normal aging. METHODS: In a delayed matching-to-sample task, subjects were exposed to a man's face, and after a delay, they were required to decide if the previously seen face was within a set of six men's faces. For half the subjects, each sample face was paired with its own outcome (differential outcomes condition); outcomes were randomly arranged for the remaining half of subjects (non-differential condition). Either short (5 second) or long (30 second) delays were interposed between the sample and the comparison stimuli. RESULTS: Results showed that relative to younger adults, older adults' performance decreased with the longer delay. However, the use of differential outcomes was able to reverse the detrimental effect of the increased delay in the elderly group, raising their performance to the level shown by younger adults. CONCLUSIONS: These findings demonstrate, for the first time, that DOP can help elderly people overcome their memory limitations, and they draw attention to the potential of this procedure as a therapeutic technique.