From the lab to the classroom: Improving children's prospective memory in a natural setting.

BACKGROUND: Laboratory-based studies have shown that children's ability to remember intentions (i.e., prospective memory; PM) can be improved by asking them to imagine performing the PM task beforehand (i.e., episodic future thinking; EFT) or to predict their PM performance. Moreover, combining the two strategies resulted in an additional improvement in children's PM performance. However, the effectiveness of these encoding strategies on real-life PM tasks is still unknown. AIMS: The aim of the present study was to evaluate the effect of EFT instructions, performance predictions, and of their combination on children's PM in a natural setting, namely in the classroom. SAMPLE: Twelve classes composed by a total of 121 children (53% females) aged between seven and 9 years participated to the study. METHODS: As a PM task, children were asked by their teachers to deliver a letter to their parents and to bring it back to school the next day. Children were divided into four groups: control, prediction, EFT, and the EFT + prediction group. Parent reports on children's everyday prospective and retrospective memory failures were also collected. RESULTS: Results showed that encoding strategies were effective in enhancing children's PM performance. However, differences compared to previous laboratory-based findings emerged since predicting PM performance resulted to be most effective in enhancing real-life PM performance. Moreover, parent reports were related to children's PM performance. CONCLUSIONS: These novel findings highlight the importance of studying PM interventions in natural settings in order to increase their ecological validity and inform educational practices.

Wider and Stronger Inhibitory Ring of the Attentional Focus in Schizophrenia.

Anomalies of attentional selection have been repeatedly described in individuals with schizophrenia spectrum disorders. However, a precise analysis of their ability to inhibit irrelevant visual information during attentional selection is not documented. Recent behavioral as well as neurophysiological and computational evidence showed that attentional search among different competing stimuli elicits an area of suppression in the immediate surrounding of the attentional focus. In the present study, the strength and spatial extension of this surround suppression were tested in individuals with schizophrenia and neurotypical controls. Participants were asked to report the orientation of a visual "pop-out" target, which appeared in different positions within a peripheral array of non-target stimuli. In half of the trials, after the target appeared, a probe circle circumscribed a non-target stimulus at various target-to-probe distances; in this case, participants were asked to report the probe orientation instead. Results suggest that, as compared to neurotypical controls, individuals with schizophrenia showed stronger and spatially more extended filtering of visual information in the areas surrounding their attentional focus. This increased filtering of visual information outside the focus of attention might potentially hamper their ability to integrate different elements into coherent percepts and influence higher order behavioral, affective, and cognitive domains.

"Teacher, forgive me, I forgot to do it!" The impact of children's prospective memory on teachers' evaluation of academic performance.

BACKGROUND: According to Munsat (1965, The concept of memory. University of Michigan), a person who makes frequent prospective memory (PM) errors is considered as having a flawed character rather than a bad memory. Given that PM completes its development only in young adulthood, this bias might occur not only within social relationships but also in school. However, little is known about the impact of this bias on academic performance. AIMS: This study aimed to evaluate the impact of children's PM on teacher's evaluations of their academic performance (i.e., grades) and social skills. SAMPLE: A total of 158 eight- and twelve-year-old children (48% females) participated in this study. METHODS: A working memory (WM) updating task was used as ongoing task (OT), in which the PM task was embedded and required participants to respond whenever certain pictures appeared. Children's social skills were measured through teacher ratings, whereas grades were collected as indicators of teachers' assessment of academic performance. Children's WM span and inhibitory control were also assessed. RESULTS: Results showed that 8- and 12-year-old children's academic performance was predicted by both PM performance and teachers' evaluations of social skills. However, social skills evaluations were not predicted by PM performance. WM span was related to grades in 8 year olds, while inhibitory control was related to PM performance in 12 year olds. CONCLUSIONS: These outcomes highlight that children's grades are not explained only by academic performance itself but also by other personal skills. Awareness of the biases which can occur when evaluating children's academic performance can help teachers to be more objective in their assessment.

Improving prospective memory in school-aged children: Effects of future thinking and performance predictions.

Recently, event-based prospective memory (PM) performance of children has been shown to benefit from different encoding strategies such as imagining the execution of a future PM task (i.e., future thinking) and making performance predictions (i.e., metacognitive monitoring). This study aimed to investigate whether and how these two encoding strategies affect PM performance alone and in combination. For this purpose, 127 children aged 8-11 years were assigned to four encoding conditions: (a) standard, (b) performance predictions, (c) future thinking, and (d) future thinking + performance predictions. The ongoing task performance costs (i.e., attentional monitoring), working memory (WM) span, and metacognitive monitoring judgments, such as task difficulty expectations, performance postdictions, confidence judgments, and strategy use, were also evaluated among participants. The results show that combining future thinking instructions with performance predictions considerably improved children's PM performance without incurring additional attentional monitoring costs. Moreover, whereas children generally tended to overestimate their PM performance, more realistic lower-performance predictions were related to higher PM scores for children in the combined condition. Finally, age, WM, and strategy use significantly predicted PM performance independent of the encoding condition. This study is the first to demonstrate that combining future thinking instructions with performance predictions enhances children's PM performance compared with each encoding strategy alone. Moreover, this work is the first to show that by simply imagining the execution of a PM task, children's prediction accuracy can be improved, which is significantly related to the PM performance advantage.

Differential involvement of left and right frontoparietal areas in visuospatial planning: An rTMS study.

The planning process consists of pre-determining an ordered series of actions to accomplish a goal. Previous research showed that the left prefrontal cortex (PFC) is likely to create the strategy for a plan, while the right PFC could be relevant for its update. These roles for the two PFCs need to be ascertained for visuospatial planning, whether communalities or differences exist with other planning tasks. Moreover, the contribution of the posterior parietal cortex (PPC) to planning still lacks evidence. Online repetitive transcranial magnetic stimulation (1 Hz) was used, and 32 participants were involved in the visuospatial planning task in a within-subject design to inhibit either the frontal or the parietal cortex of either the left or the right hemisphere. The goal consisted of evaluating the contribution of these cortical regions, also controlling for gender, in a computerized version of the travelling salesman problem (TSP), the "Maps" task. The results showed that all the stimulated sites produced significant differences in their involvement, reflected in several parameters (such as initial planning and execution times, strategies and heuristics used), with respect to the control group. The roles for the two PFCs were generally confirmed in all measures except path length, while the contribution of the PPC emerged throughout the measures related to the ongoing execution. We concluded that the results obtained with the TSP paradigm were consistent with results obtained using other tasks used to study the planning process (such as the Tower of London) for the evaluation of PFC contribution. In addition, we showed that the contribution of the PPC to the planning process has probably been underestimated.

Performance predictions and postdictions in prospective memory of school-aged children.

Prospective memory (PM) undergoes important developmental changes during the primary school years, particularly around 7 and 8 years of age. Recent studies have suggested that, as well as executive functions (EFs), PM development also benefits from age-related increments in metamemory (MM) abilities. The primary aim of the current study was to explore the role of MM monitoring and control processes (i.e., procedural MM) of 7- and 8-year-old children in a PM task including specific cues. Monitoring processes were assessed by asking children to judge their own PM performance before (predictions) and after (postdictions) in performing a PM task. In addition, children were asked to report the strategy they used to remember the PM task. Reactive effects of making predictions and using strategies were assessed via both an ongoing task (OT) and PM performance. EF and declarative MM performance was also examined. Results showed that children who were asked to predict PM performance had faster PM response times (RTs), but not higher accuracy rates, than children in a control group. However, strategy use affected both PM and OT performance, with those children reporting active strategy use obtaining higher PM accuracy rates and slower OT RTs. Finally, switching abilities were also predictive of OT performance. This investigation highlights the importance of studying MM monitoring and control processes in relation to children's PM.

The role of declarative and procedural metamemory in event-based prospective memory in school-aged children.

Prospective memory (PM) develops considerably during the primary school years (7 or 8years of age). Developmental changes have been mainly related to executive functions, although it has been recently suggested that PM would also potentially benefit from metamemory (MM). To date, only procedural MM, operationalized as performance predictions, has been investigated in relation to PM, whereas declarative MM has remained unexplored. Adults' performance has been shown to improve with predictions, but only in a resource-demanding (i.e., categorical) PM task rather than a more automatic (i.e., specific) one. The aim of the current investigation was to study whether PM performance of 7-year-old children (N=59) would benefit from performance predictions. Thus, half of the children predicted their performance and half of them received standard instructions for two PM tasks: one including categorical PM targets and one including specific ones. To investigate the processes underlying the retrieval of PM targets and the effect of predictions, we obtained measures for declarative MM, inhibitory control, and working memory (WM). Results revealed that children benefitted from performance predictions in the categorical PM task but not in the specific one. This advantage caused slower ongoing task response times, suggesting that strategic monitoring processes were enhanced. Moreover, PM performance was related to WM capacity and declarative MM. However, declarative MM mainly predicted PM advantage in the prediction group, showing that children with high MM knowledge benefitted especially from performance predictions. These findings are the first showing the important relation among procedural MM, declarative MM, and PM in school-aged children.

Content encapsulation in consciousness is likely to be incomplete.

Although the passive frame theory (PST) seems to be very plausible, the encapsulation of content generation deserves further elaboration. Many concepts and data considering the capacity theory, perception, and higher cognitive processes seem to contradict this principle. In general, PST can be suitable in many cases, but it needs to be completed by other mechanisms.

A transcranial magnetic stimulation study on response activation and selection in spatial conflict.

In choice reaction tasks, subjects typically respond faster when the relative spatial positions of stimulus and response correspond than when they do not, even when spatial information is irrelevant to the task (e.g. in the Simon task). Cognitive models attribute the Simon effect to automatic response activation elicited by spatial information, which facilitates or competes with the controlled selection of the correct response as required by task demands. In the present study, we investigated the role of the dorsal premotor cortex (PMd) in response activation and selection during spatial conflict. We applied single-pulse transcranial magnetic stimulation (TMS) to the PMd of the right and left hemispheres during the execution of a Simon task, at different times after the onset of the visual stimulus. The results showed that TMS produced a different effect on subjects' performance in two separate time windows. When TMS was applied at an early time [160-ms stimulus onset asynchrony (SOA)], we observed suppression of the Simon effect, resulting from a delay of corresponding trials. When TMS was applied at a late time (220 and 250-ms SOA), we observed an increase in the Simon effect, resulting from a delay of non-corresponding trials. These outcomes revealed that the PMd is involved both in the activation of the spatially triggered response and in response selection during spatial conflict.

Low-frequency rTMS inhibitory effects in the primary motor cortex: Insights from TMS-evoked potentials.

The neuromodulatory effects of repetitive transcranial magnetic stimulation (rTMS) have been mostly investigated by peripheral motor-evoked potentials (MEPs). New TMS-compatible EEG systems allow a direct investigation of the stimulation effects through the analysis of TMS-evoked potentials (TEPs). We investigated the effects of 1-Hz rTMS over the primary motor cortex (M1) of 15 healthy volunteers on TEP evoked by single pulse TMS over the same area. A second experiment in which rTMS was delivered over the primary visual cortex (V1) of 15 healthy volunteers was conducted to examine the spatial specificity of the effects. Single-pulse TMS evoked four main components: P30, N45, P60 and N100. M1-rTMS resulted in a significant decrease of MEP amplitude and in a significant increase of P60 and N100 amplitude. There was no effect after V1-rTMS. 1-Hz rTMS appears to increase the amount of inhibition following a TMS pulse, as demonstrated by the higher N100 and P60, which are thought to originate from GABAb-mediated inhibitory post-synaptic potentials. Our results confirm the reliability of the TMS-evoked N100 as a marker of cortical inhibition and provide insight into the neuromodulatory effects of 1-Hz rTMS. The present finding could be of relevance for therapeutic and diagnostic purposes.

When working memory updating requires updating: analysis of serial position in a running memory task.

This study aimed to investigate updating in working memory (WM), analyzing the effects of task demand and memory resources on serial position curve (SPC), in a running memory task with slow pace presentation and a probed recognition procedure. These task conditions were supposed to produce an easier WM updating task, which may allow evidencing whether the task is performed through an active or a passive updating. Serial position curves were compared in conditions of high or low memory load, and with or without interference of a secondary (prospective memory, PM) task. With either a high WM load, or a high PM load, results showed a SPC with both primacy and recency effects, indicating the use of an active strategy. When resources were taken up by both PM task and high WM demand the usual pattern with only recency effect was obtained. Taken together, these findings support the ideas that 1--people can effectively update WM, and 2--the performance is dependent on both memory and executive resource availability.

TMS on right frontal eye fields induces an inflexible focus of attention.

The focus of spatial attention can be not only oriented to a particular location, but also adjusted in its size to select visual information from a narrow (zoom-in) or broad (zoom-out) region of the visual field. Attentional orienting, saccades programming, and visual search have been linked to the frontal eye fields (FEF) activity. However, the FEF causal role in the frontoparietal network for the attentional focus size modulation remains unclear. Here, we delivered single-pulse transcranial magnetic stimulation (TMS) on FEF while participants performed an attentional zooming task. They were asked to detect a visual target appearing at 3 eccentricities from the fixation. Two cue types modulated the size of the attended region: a small cue was employed to narrow the attentional focus, whereas a large cue induced participants to broaden the attended region. Results showed that TMS delivered on the right FEF, but not on the left FEF, was able to interfere with both zoom-in and zoom-out attentional mechanisms. Our results provide the first evidence of the right FEF casual role in the attentional zooming control and give new insights into the neural mechanisms of dysfunctional spatial attention deployment shown in neurodevelopmental disorders, such as autism and dyslexia.

Touching motion: rTMS on the human middle temporal complex interferes with tactile speed perception.

Brain functional and psychophysical studies have clearly demonstrated that visual motion perception relies on the activity of the middle temporal complex (hMT+). However, recent studies have shown that hMT+ seems to be also activated during tactile motion perception, suggesting that this visual extrastriate area is involved in the processing and integration of motion, irrespective of the sensorial modality. In the present study, we used repetitive transcranial magnetic stimulation (rTMS) to assess whether hMT+ plays a causal role in tactile motion processing. Blindfolded participants detected changes in the speed of a grid of tactile moving points with their finger (i.e. tactile modality). The experiment included three different conditions: a control condition with no TMS and two TMS conditions, i.e. hMT+-rTMS and posterior parietal cortex (PPC)-rTMS. Accuracies were significantly impaired during hMT+-rTMS but not in the other two conditions (No-rTMS or PPC-rTMS), moreover, thresholds for detecting speed changes were significantly higher in the hMT+-rTMS with respect to the control TMS conditions. These findings provide stronger evidence that the activity of the hMT+ area is involved in tactile speed processing, which may be consistent with the hypothesis of a supramodal role for that cortical region in motion processing.

Single pulse TMS induced disruption to right and left parietal cortex on addition and multiplication.

Whether or not mathematical operations are dependent on verbal codes in left hemisphere areas - particularly the left intraparietal sulcus - remains an issue of intense debate. Using single pulse transcranial magnetic stimulation directed at horizontal and ventral regions of the left and right intraparietal sulcus, we examined disruption to reaction times in simple addition and multiplication. Results indicate that these two operations differ in the pattern of lateralization across time for the two areas studied. These show that computational efficiency is not specifically dependent on left hemisphere regions and, in particular, that efficiency in multiplication is dependent on the ventral region of the intraparietal sulcus in the right hemisphere considered to be critical for motion representation and automatization.

Timing spatial conflict within the parietal cortex: a TMS study.

Orienting and motor attention are known to recruit different regions within right and left parietal lobes. However, the time course and the role played by these modules when visual information competes for different motor response are still unknown. To deal with this issue, single-pulse TMS was applied over the angular (AG) and the supramarginal (SMG) gyri of both hemispheres at several time intervals during the execution of a Simon task. Suppression of the conflict between stimulus and response positions (i.e., the Simon effect) was found when TMS pulse was applied 130 msec after stimulus onset over the right AG and after 160 msec when applied over the left AG and SMG. Interestingly, only stimulation of the left SMG suppressed the asymmetry in conflict magnitude between left- and right-hand responses, usually observed in the Simon task. The present data show that orienting attention and motor attention processes are temporally, functionally, and spatially separated in the posterior parietal cortex, and both contribute to prime motor response during spatial conflict.

Functional inhibition of the human middle temporal cortex affects non-visual motion perception: a repetitive transcranial magnetic stimulation study during tactile speed discrimination.

The visual motion-responsive middle temporal complex (hMT+) is activated during tactile and aural motion discrimination in both sighted and congenitally blind individuals, suggesting a supramodal organization of this area. Specifically, non-visual motion processing has been found to activate the more anterior portion of the hMT+. In the present study, repetitive transcranial magnetic stimulation (rTMS) was used to determine whether this more anterior portion of hMT+ truly plays a functional role in tactile motion processing. Sixteen blindfolded, young, healthy volunteers were asked to detect changes in the rotation velocity of a random Braille-like dot pattern by using the index or middle finger of their right hand. rTMS was applied for 600 ms (10 Hz, 110% motor threshold), 200 ms after the stimulus onset with a figure-of-eight coil over either the anterior portion of hMT+ or a midline parieto-occipital site (as a control). Accuracy and reaction times were significantly impaired only when TMS was applied on hMT+, but not on the control area. These results indicate that the recruitment of hMT+ is necessary for tactile motion processing, and thus corroborate the hypothesis of a 'supramodal' functional organization for this sensory motion processing area.

Prospective memory and working memory: asymmetrical effects during frontal lobe TMS stimulation.

The role of working memory (WM) for the realization of an intended action (prospective memory, PM) has been debated in recent neuropsychological literature. The present study aimed to assess whether WM and PM share resources or are, alternatively, two distinct mechanisms. A verbal task was used, which manipulated the cognitive demand of both WM and PM dimensions on an event-based prospective task. Transcranial magnetic stimulation (TMS) was also employed to clarify the causal contribution of frontal areas previously related to WM, to the PM process. The prospective task required the participant to respond whenever a word appeared which had been presented before the beginning of the task. Two ongoing tasks were administered: an updating WM task (in two conditions of medium and high WM demands) and a lexical decision task (representing a low WM demand). In the first two experiments, higher PM demand affected WM only at higher loads, but the PM load effect was independent of WM, showing asymmetrical behavioural effects. In the third experiment, single pulse TMS was applied to left and right dorsolateral prefrontal cortices. When applied to the experimental sites, stimulation increased error rates of the PM task, while the effect was only marginal in the WM task. The effect was bilateral, since there was no difference between left and right stimulation sites. These findings demonstrated, from both behavioural and neurofunctional perspectives, that WM and PM processes are not based on the same memory system, but PM may require WM resources at high demand.

Gender differences in visuospatial planning: an eye movements study.

Gender studies report a male advantage in several visuospatial abilities. Only few studies however, have evaluated differences in visuospatial planning behaviour with regard to gender. This study was aimed at exploring whether gender may affect the choice of cognitive strategies in a visuospatial planning task and, if oculomotor measures could assist in disentangling the cognitive processes involved. A computerised task based on the travelling salesperson problem paradigm, the Maps test, was used to investigate these issues. Participants were required to optimise time and space of a path travelling among a set of sub-goals in a spatially constrained environment. Behavioural results suggest that there are no gender differences in the initial visual processing of the stimuli, but rather during the execution of the plan, with males showing a shorter execution time and a higher path length optimisation than females. Males often showed changes of heuristics during the execution while females seemed to prefer a constant strategy. Moreover, a better performance in behavioural and oculomotor measures seemed to suggest that males are more able than females in either the optimisation of spatial features or the realisation of the planned scheme. Despite inconclusive findings, the results support previous research and provide insight into the level of cognitive processing involved in navigation and planning tasks, with regard to the influence of gender.