Learning capacity in early-stage Alzheimer's disease: The role of feedback during learning on memory performance.

Alzheimer's disease is characterized by a decline in episodic memory and executive functioning, hampering learning ability. Insight into outcome-based learning capacity may be relevant for optimizing the learning potential of these patients. To date, mixed results have been found in studies in which cognitively impaired participants have to learn based on positive and negative outcomes. In this study, we investigated the role of negative and positive feedback on memory performance and participants' ability to adjust their behaviour accordingly in a sample of 23 early-stage AD patients and 23 matched healthy controls. We administered a novel computerized object-location memory task, in which participants were instructed to learn and memorize the locations of different everyday objects following errorless learning (EL) and trial-and-error learning (TEL). A separate probabilistic TEL task was employed in which participants had to learn how to adjust their behaviour based on positive and negative feedback. EL had a beneficial general effect on memory performance for object locations. However, this effect was not larger in early-stage AD patients compared to controls and error frequency during acquisition of object locations was unrelated to later recall performance. No group differences were found on the probabilistic learning task with respect to learning performance over time and based on positive and negative feedback. Although the error monitoring system seems intact in patients with early-stage AD, errors during learning are likely acting as a source of interference causing difficulty in storage or retrieval of object locations.

Errorless and trial-and-error learning of object locations in patients with executive deficits after brain injury.

Studies investigating the efficacy of errorless learning (EL), a rehabilitation method in which the occurrence of errors during learning are eliminated, have predominantly involved patients with memory impairment. However, the most recent perspective on the underlying mechanism of EL explicitly takes executive processes into account. The aim of this study was to investigate whether EL of object locations is beneficial for memory performance compared to trial-and-error learning (TEL) in patients with acquired brain injury (ABI) experiencing executive deficits (N = 15) and matched healthy controls (N = 15). Participants completed an EL and TEL condition of a computerized spatial learning task, in which the location of everyday objects had to be memorized. The number of errors made during learning was predetermined, varying from 0 (EL condition) to 1, 2, 3, 4 or 5 errors (TEL condition). Results showed a beneficial effect of EL on memory performance in both ABI patients and controls (p < .001), but this advantage was not larger in ABI patients compared to controls and was not moderated by the amount of errors made during learning.

So what'cha want? The impact of individualised rewards on associative learning in psychopathic offenders.

Psychopathic individuals typically present with associative learning impairments under explicit learning conditions. The present study aimed to investigate whether the formation of stimulus-outcome associations, as well as updating of these associations after changed contingencies, could be improved by using rewards with sufficiently high subjective values. To this end, 20 psychopathic offenders, 17 non-psychopathic offenders and 18 healthy controls performed a passive avoidance task with a reversal phase under three motivational conditions, using naturalistic rewards. The subjective values of the rewards were assessed a priori for each individual participant using a visual analogue scale. The correspondence of these values to their internal representation was confirmed by analyses of brain potentials. Analyses using both signal detection theory and classical approaches indicated that psychopathic offenders performed worse compared to the other groups during passive avoidance learning. However, using the signal detection approach, we found this deficiency to be present only when a hypothetical reward was used ('neutral reward' condition), whereas psychopathic offenders performed similar to the other groups when naturalistic rewards could be obtained ('low reward' and 'high reward' conditions). Furthermore, traditional analyses suggested that psychopathic offenders had more hits than the other groups during reversal learning, but the signal detection approach indicated that no effects of group or condition were present. Analysis of win-stay and lose-shift behaviour showed that psychopathic offenders were less likely to stay with a rewarded response during passive avoidance learning in the neutral reward condition. In addition, regardless of experimental phase or condition, psychopathic offenders were less likely to stop responding to a particular stimulus after receiving negative feedback. Although the approaches employed did not lead to unequivocal results, our findings suggest that psychopathic offenders do have the ability to adapt their behaviour to environmental contingencies when positive reinforcers with sufficiently high subjective values are used.

Prevention is better than cure: effects of errors on memory performance during spatial learning in healthy aging.

BACKGROUND: Healthy aging is accompanied by a decline in learning ability and memory capacity. One widely-studied method to improve learning outcome is by reducing the occurrence of errors during learning (errorless learning; EL). However, there is also evidence that committing errors during learning (trial-and-error learning; TEL) may benefit memory performance. We argue that these inconsistent findings could be driven by a lack of control over the error frequency in traditional EL and TEL paradigms. AIM: This study employed a spatial learning task to study EL and TEL and to determine the impact of error frequency on memory recall in healthy older adults (OA; N = 68) and young adults (YA; N = 60). METHOD: Four groups of participants (YA-EL, YA-TEL, OA-EL, OA-TEL) were instructed to first place and memorize the locations of everyday objects in a chest of drawers presented on a computer screen, and in whom memory recall performance was later tested. In the TEL condition, the amount of errors made before the correct drawer was 'found' was predetermined, varying from 0 to 5. During the EL condition, every first attempt was correct (i.e., no errors were made). RESULTS: We found better overall performance in YA compared to OA and a beneficial effect of EL in both age groups. However, the amount of errors committed during learning did not influence accuracy of memory recall. CONCLUSION: Our results indicate that elimination of errors during learning can benefit memory performance in both YA and OA compared to TEL.

The impact of error frequency on errorless and errorful learning of object locations using a novel paradigm.

Errorless learning (EL) is an approach in which errors are eliminated or reduced as much as possible while learning of new information or skills. In contrast, during trial-and-error - or errorful - learning (TEL) errors are not reduced and are often even promoted. There is a complex and conflicting pattern of evidence whether EL or TEL may result in better memory performance. One major confound in the extant literature is that most EL studies have not controlled for the number of errors made during TEL, resulting in a large variability in the amount of errors committed. This variability likely explains why studies on the cognitive underpinnings of EL and TEL have produced mixed findings. In this study, a novel object-location learning task was employed to examine EL and TEL in 30 healthy young adults. The number of errors was systematically manipulated, allowing us to investigate the impact of frequency of errors on learning outcome. The results showed that recall from memory was significantly better during EL. However, the number of errors made during TEL did not influence the performance in young adults. Altogether, our novel paradigm is promising for measuring EL and TEL, allowing for more accurate analyses to understand the impact of error frequency on a person's learning ability and style.

Unfair offers, unfair offenders? Fairness considerations in incarcerated individuals with and without psychopathy.

Offenders with psychopathy have often committed crimes violating social norms, which may suggest a biased moral reasoning in psychopathy. Yet, as findings on utilitarian decisions remain conflicting, the current study investigated different aspects of fairness considerations in offenders with psychopathy, offenders without psychopathy and healthy individuals (N = 18/14/18, respectively). Unfair offers in a modified Ultimatum Game (UG) were paired with different unselected alternatives, thereby establishing the context of a proposal, and made under opposing intentionality constraints (intentional vs. unintentional). As in previous studies, unfair offers were most often rejected when the alternative was fair and when the offer was made intentionally. Importantly, however, offenders with psychopathy demonstrated a similar rejection pattern to that of healthy individuals, i.e., taking the unselected alternative into account. In contrast, delinquents without psychopathy did not adjust their decision behavior to the alternatives to an offer, suggesting stronger impairments in social decision-making. Crucially, the mechanisms and processes underlying rejection decisions might differ, particularly with regard to cognitive vs. emotional competencies. While preserved cognitive perspective-taking could drive seemingly intact decision patterns in psychopathy, emotional empathy is likely to be compromised.

Reversal deficits in individuals with psychopathy in explicit but not implicit learning conditions.

BACKGROUND: Psychopathy is a severe personality disorder that has been linked to impaired behavioural adaptation during reinforcement learning. Recent electrophysiological studies have suggested that psychopathy is related to impairments in intentionally using information relevant for adapting behaviour, whereas these impairments remain absent for behaviour relying on automatic use of information. We sought to investigate whether previously found impairments in response reversal in individuals with psychopathy also follow this dichotomy. We expected response reversal to be intact when the automatic use of information was facilitated. In contrast, we expected impaired response reversal when intentional use of information was required. METHODS: We included offenders with psychopathy and matched healthy controls in 2 experiments with a probabilistic cued go/no-go reaction time task. The task implicated the learning and reversal of 2 predictive contingencies. In experiment 1, participants were not informed about the inclusion of a learning component, thus making cue-dependent learning automatic/incidental. In experiment 2, the instructions required participants to actively monitor and learn predictive relationships, giving learning a controlled/intentional nature. RESULTS: While there were no significant group differences in acquisition learning in either experiment, the results revealed impaired response reversal in offenders with psychopathy when controlled learning was facilitated. Interestingly, this impairment was absent when automatic learning was predominant. LIMITATIONS: Possible limitations are the use of a nonforensic control group and of self-report measures for drug use. CONCLUSION: Response reversal deficits in individuals with psychopathy are modulated by the context provided by the instructions, according to the distinction between automatic and controlled processing in these individuals.