Rhesus monkeys (<Emphasis Type="Italic">Macaca mulatta</Emphasis>) discriminate between knowing and not knowing and collect information as needed before acting

Humans use memory awareness to determine whether relevant knowledge is available before acting, as when we determine whether we know a phone number before dialing. Such metacognition, or thinking about thinking, can improve selection of appropriate behavior. We investigated whether rhesus monkeys (Macaca mulatta) are capable of a simple form of metacognitive access to the contents of short-term memory. Monkeys chose among four opaque tubes, one of which concealed food. The tube containing the reward varied randomly from trial to trial. On half the trials the monkeys observed the experimenter baiting the tube, whereas on the remaining trials their view of the baiting was blocked. On each trial, monkeys were allowed a single chance to select the tube containing the reward. During the choice period the monkeys had the opportunity to look down the length of each tube, to determine if it contained food. When they knew the location of the reward, most monkeys chose without looking. In contrast, when ignorant, monkeys often made the effort required to look, thereby learning the location of the reward before choosing. Looking improved accuracy on trials on which monkeys had not observed the baiting. The difference in looking behavior between trials on which the monkeys knew, and trials on which they were ignorant, suggests that rhesus monkeys discriminate between knowing and not knowing. This result extends similar observations made of children and apes to a species of Old World monkey, suggesting that the underlying cognitive capacities may be widely distributed among primates.     

Persistent overconfidence despite practice: The role of task experience in preschoolers’ recall predictions

In three experiments, preschoolers’ ability to predict their picture recall was examined. Children studied 10 pictures, predicted how many they would recall, and then attempted to recall them. This study-prediction-recall trial was repeated multiple times with new pictures on each trial. In Experiment 1, children were overconfident on the initial trial, and this overconfidence persisted across three trials. In Experiment 2, children predicted either their own performance or another child’s performance. Their predictions were overconfident across all trials regardless of whether they made predictions for themselves or for another child, suggesting that wishful thinking cannot fully account for their overconfidence. In Experiment 3, some children postdicted their previous recall performance prior to making each prediction. Although their postdictions were quite accurate, their predictions were still overconfident across five trials. Preschoolers’ overconfidence was remarkably resistant to the repeated experience of recalling fewer pictures than the children had predicted. Even asking them to report the number that they recalled on a previous trial, which they could do accurately, did not cause them to lower their predictions across trials.     

Reminiscence,forgetting, and hypermnesia using face–name learning: Isolating the effects using recall and recognition memory measures

A face–name learning paradigm was used to study phenomena involved in reminiscence, forgetting, and hypermnesia. Individuals introduced themselves on videotape while participants tried to learn their names. The presence of cues during testing increased overall performance but decreased hypermnesia in Experiment 1. Significant recognition memory effects were found for reminiscence and hypermnesia in Experiments 2 and 3. Experiment 3 also showed no interference from activities between testing sessions, but did show facilitating effects from exposure to photographs of target faces and to exposure of target names. The results were interpreted as showing support for reminiscence effects being primarily caused by imagery redintegration and effects consistent with stimulus sampling theories.     

Relations between children’s metamemory and strategic performance: Time-varying covariates in early elementary school

Although much is known about the development of memory strategies and metamemory during childhood, evidence for linkages between these memory skills, either concurrently or over time, has been limited. Drawing from a longitudinal investigation of the development of memory, repeated assessments of children’s (N = 107) strategy use and declarative metamemory were made to examine the development of these skills and the relations between them over time. Latent curve models were used first to estimate the trajectories of children’s strategy use and metamemory and then to examine predictors of children’s performance in each of these domains. Children’s metamemory at the beginning of Grade 1 was linked to child- and home-level factors, whereas the development of both skills was related to maternal education level. Additional modeling of the longitudinal relations between strategic sorting and metacognitive knowledge indicated that metamemory at earlier time points was predictive of subsequent strategy use.     

Time’s up! Involvement of metamemory knowledge,executive functions,and time monitoring in children’s prospective memory performance

This study examined time-based prospective memory (PM) in children and explored the possible involvement of metamemory knowledge and executive functions in the use of an appropriate time-monitoring strategy depending on the ongoing task’s difficulty. Specifically, a sample of 72 typically developing children aged 4, 6, and 9 years old were given an original PM paradigm composed of both an ongoing procedural activity and a PM task. Half of the participants (expert group) were trained in the ongoing activity before the prospective test. As expected, results show that time monitoring had a positive effect on children’s PM performance. Furthermore, mediation analyses reveal that strategic time monitoring was predicted by metamemory knowledge in the expert group but only by executive functions in the novice group. Overall, these findings provide interesting avenues to explain how metamemory knowledge, strategy use, and executive functions interact to improve PM performance during childhood.     

Metamemory in tufted capuchin monkeys (Cebus apella)

Whereas evidence for metacognition by nonhuman primates has been obtained in great apes and old world monkeys, it is weaker in new world monkeys. For instance, capuchin monkeys may fail to recognize their own knowledge of the location of invisible bait. In the present study, we tested whether tufted capuchin monkeys would flexibly change their behavior in a delayed matching-to-sample (DMTS) test depending upon the strength of their memory trace of the sample. In Experiment 1, two monkeys were tested on a modified 9-alternative DMTS task with various delays on a computerized display. In some trials, the monkeys could choose whether to go for a memory test or for a simple key touch as an escape from the test. In other trials, they were forced to go for the memory test. Both monkeys escaped from the memory test more often when their matching accuracy on forced tests was lower. In one of the monkeys, the matching accuracies on chosen memory tests decreased more slowly as a function of delay length, and were higher after long delays than those on forced memory tests. This suggests that at least one capuchin monkey was able to recognize the strength of his own memory trace. Experiment 2 employed occasional no-sample tests, in which the monkeys faced the task choice without presentation of any sample for the trial. The monkey who was successful in Experiment 1 declined the memory test more often in no-sample trials than regular trials, further indicating metamemory in this individual. In Experiment 3, this successful monkey received a task, in which he was sometimes able to choose between shape MTS or texture MTS tasks. However, his matching accuracies did not differ between chosen tasks and forced tasks. Thus, the metamemory possessed by this new world monkey species may be more like a flag, showing strength of memory trace, than an elaborate representation showing details of the memory trace.     

The development of the memorability-based strategy: insight from a training study

We investigated whether the memorability-based strategy, a process supporting the rejection of nonexperienced event occurrence, could be promoted through training. The performance of children who received memorability-based training was compared with that of (a) children who received source-monitoring training and (b) children who did not receive any specific training but were instructed to be as accurate as possible. Participants (142 6- to 10-year-olds) enacted common and bizarre actions. Eighteen days later, participants received misinformation about the first session. Five days after being misinformed, children were questioned about the first session. Compared with children in the no training condition, those in both training conditions reported significantly more true events, but only older children who received the memorability-based training were more likely to reject bizarre suggested events. Age interacted with action type when metacognitive assessments about false event rejection were examined, consistent with the idea that the use of the memorability-based strategy develops late during the elementary school years.     

Attributions for Memory Performance in Adulthood: Age Differences and Mediation Effects

We examined age differences in attributions to internal (controllable and uncontrollable), external (uncontrollable), and unstable factors for performance on a free recall memory task in 149 young, middle-aged, and older adults. Attributions varied by age and by level of memory performance. Middle-aged and older adults rated internal, uncontrollable factors (ability and genes) as more influential for high performance than for low performance, and they were less likely than young adults to attribute low performance to these factors. Within age groups, only the older adults rated memory ability as more influential than strategy use, even though they were as likely as the other age groups to use a categorization strategy. Attributions to both internal controllable (strategy use) and uncontrollable (ability) factors as well as to health were associated with better memory performance. These attributions partially mediated the relationship between age and memory performance. Thus, attributions may provide some insight into sources of age differences in memory performance.     

Importance effects on performance in event‐based prospective memory tasks

In the present study we manipulated the importance of performing two event‐based prospective memory tasks. In Experiment 1, the event‐based task was assumed to rely on relatively automatic processes, whereas in Experiment 2 the event‐based task was assumed to rely on a more demanding monitoring process. In contrast to the first experiment, the second experiment showed that importance had a positive effect on prospective memory performance. In addition, the occurrence of an importance effect on prospective memory performance seemed to be mainly due to the features of the prospective memory task itself, and not to the characteristics of the ongoing tasks that only influenced the size of the importance effect. The results suggest that importance instructions may improve prospective memory if the prospective task requires the strategic allocation of attentional monitoring resources.     

Object permanence in lemurs

Object permanence, the ability to mentally represent objects that have disappeared from view, should be advantageous to animals in their interaction with the natural world. The objective of this study was to examine whether lemurs possess object permanence. Thirteen adult subjects representing four species of diurnal lemur (Eulemur fulvus rufus, Eulemur mongoz, Lemur catta and Hapalemur griseus) were presented with seven standard Piagetian visible and invisible object displacement tests, plus one single visible test where the subject had to wait predetermined times before allowed to search, and two invisible tests where each hiding place was made visually unique. In all visible tests lemurs were able to find an object that had been in clear view before being hidden. However, when lemurs were not allowed to search for up to 25-s, performance declined with increasing time-delay. Subjects did not outperform chance on any invisible displacements regardless of whether hiding places were visually uniform or unique, therefore the upper limit of object permanence observed was Stage 5b. Lemur species in this study eat stationary foods and are not subject to stalking predators, thus Stage 5 object permanence is probably sufficient to solve most problems encountered in the wild.     

Further evidence for the efficacy of a metacognitive group training in schizophrenia

Metacognitive training (MCT) for patients with schizophrenia is a novel psychological group treatment targeting cognitive biases putatively involved in the pathogenesis of schizophrenia (e.g. jumping to conclusions, overconfidence in errors). Its eight modules are available cost-free online in many languages. In the present study, 36 subacute or remitted patients were randomly allocated to either the MCT or a wait-list group who received treatment-as-usual (TAU). Baseline and post assessments were 8 weeks apart and were performed blind to group status. MCT showed significantly greater improvement on the following parameters relative to the TAU group: delusion distress (PSYRATS), memory and social quality of life. In the MCT group, the rate of jumping to conclusions bias was reduced after training. No differences occurred on the PANSS. The present study confirms prior reports that MCT exerts beneficial effects on some cognitive and symptomatic parameters.     

Cognitive function and depression in symptom resolution in schizophrenia patients treated with an atypical antipsychotic

OBJECTIVE: To investigate which cognitive and affective features contribute most to responder/non-responder group separation during a switching trial with atypical antipsychotic. DESIGN: A prospective open trial with an atypical antipsychotic (olanzapine). PATIENTS: One hundred and thirty-four patients meeting diagnostic criteria for schizophrenia, schizophreniform or schizoaffective disorder began an 8-week open-label olanzapine treatment at a dose of 5 mg/day which was increased to 10 mg/day after one week. INTERVENTIONS: Olanzapine during 8 weeks. Patients were considered as responders if their BPRS score decreased of at least 20% (n = 96) and non-responders if it did not (n = 38). Neuropsychological assessments were carried out at baseline, at four and at eight weeks. RESULTS: Neurocognitive measures were analyzed for discriminate factors between responder and non-responder groups. A regression analysis was applied to explain the effects of depression on each cognitive variable. Depression was found to be a weak discriminant factor, however this finding could not firmly establish that depression is a potential factor in explaining deficits and improvements in cognition.