To do or not to do? Prospective memory versus response inhibition in autism spectrum disorder and attention-deficit/hyperactivity disorder

Practice is the best of all instructors-Effects of enactment encoding and episodic future thinking on prospective memory performance in high-functioning adults with autism spectrum disorder

Prospective memory (PM) is the ability to remember to carry out intended actions in the future. The present study investigated the effects of episodic future thinking (EFT) and enactment encoding (EE) on PM performance in autistic adults (ASD). A total of 72 autistic individuals and 70 controls matched for age, gender, and cognitive abilities completed a computerized version of the Dresden breakfast Task, which required participants to prepare breakfast following a set of rules and time restrictions. A two (group: ASD vs. controls) by three (encoding condition: EFT vs. EE vs. standard) between-subjects design was applied. Participants were either instructed to engage in EFT or EE to prepare to the different tasks prior to performing the Dresden breakfast or received standard instructions. Analyses of variance were conducted. Autism-spectrum-disorders (ASD) participants did not differ from control participants in their PM performance, regardless of which strategy they used. Compared to the standard condition, EE but not EFT improved time-based PM performance in all participants. This is the first study to find spared time-based PM performance in autistic individuals. The results confirm earlier results of beneficial effects of EE on PM performance. Findings are discussed with regards to the methodology used, sample composition as well as autistic characteristics.

Time-Based and Event-Based Prospective Memory in Adults with Autism Spectrum Disorder: A Virtual Week Investigation

PURPOSE

Autism spectrum disorder (ASD) is a complex developmental condition including persistent challenges with social communication, restricted interests, and repetitive behavior. Though prospective memory failures are commonly observed in ASD population it has been less studied among adults with ASD. Prospective memory (PM) refers to the execution of delayed intentions. There are contradictory findings of regular and irregular prospective memory task among autistic adults. The present study is an attempt to investigate prospective memory performance among adults with autism spectrum disorder using the Virtual Week board game.

METHOD

Virtual Week (Rendell & Craik, 2000) (3-day Version) is a computerized board game in which participants after rolling a die move token clockwise around the board. Each round of the board represents one virtual "day." Adults between 16 and 25 years of age who were diagnosed with ASD (N = 23) were compared with non-ASD (N = 26) adults.

RESULTS

Analyses of variance were used to analyze the data. Results revealed that autistic adults as compared to normal adults showed poorer performance on time-based task than on event-based task. A significant difference was evident between regular and irregular prospective memory tasks across both tasks among autistic adults. Results also revealed that ASD difficulties are associated with the prospective component of the irregular task.

CONCLUSIONS

Prospective memory failures are widely observed in ASD group, and have important implications for functional independence. The findings of this study provide insight into prospective memory challenges that adults with autism spectrum disorder face in a daily basis.

Do emotionally salient cues improve prospective memory performance in children and adolescents with autism?

BACKGROUND

Prospective memory (PM) describes the ability to initiate and perform a planned action after a delay. Previous studies suggest reduced PM in autism spectrum disorder (ASD); especially when tasks put high demands on executive control resources. Increasing cue salience by presenting emotional cues improves PM performance in non-autistic populations.

AIMS

To explore whether children with ASD, whose processing of emotionally connoted information might differ from that of typically developing children, may also benefit from this type of salience in PM tasks.

METHODS AND PROCEDURES

Twenty-five children with and 25 children without ASD completed a 1-back ongoing task into which an event-based PM task was embedded. Emotional salience of PM cues was varied.

OUTCOMES AND RESULTS

Children with ASD performed as well as children without ASD on the PM task and equally benefited from emotionally salient cues. Specifically, negative cues increased PM performance compared to neutral cues in both groups CONCLUSIONS AND IMPLICATIONS: The findings are consistent with the multiprocess framework which postulates that salient PM cues increase performance by promoting automatic intention retrieval and reducing executive control demands. Children with ASD seem to show similar comprehension and accessibility to emotional cues as typically developing children.

Did you hear? Auditory prospective memory cues are more beneficial for autistic than for non-autistic children and adolescents

BACKGROUND

The transition from primary to secondary school is particularly difficult for autistic children, a transition underpinned by an increase in prospective memory (PM) demands.

AIMS

To better understand PM in autistic children of the relevant age range and its underlying processes, the current study investigated the impact of cue salience (distinctiveness) on PM in autistic and non-autistic children and adolescents. The study was unique in manipulating the visual and auditory salience of PM cues. Salient cues are assumed to put lower demands on executive control resources as compared to cues that blend in with the ongoing activity.

METHODS AND PROCEDURES

The children completed a computer-based categorisation task in which an event-based PM task was embedded. The salience of PM cues was manipulated (low, high visual and high auditory salience).

OUTCOMES AND RESULTS

Results revealed that both groups benefitted from an increase in visual and auditory salience, but only autistic participants were faster to respond to auditory cues.

CONCLUSIONS AND IMPLICATIONS

Increased cue salience improved PM performance for all children. Positive effects of auditory cues were especially evident in autistic children.

"No Way Out Except From External Intervention": First-Hand Accounts of Autistic Inertia

This study, called for by autistic people and led by an autistic researcher, is the first to explore ‘autistic inertia,’ a widespread and often debilitating difficulty acting on their intentions. Previous research has considered initiation only in the context of social interaction or experimental conditions. This study is unique in considering difficulty initiating tasks of any type in real life settings, and by gathering qualitative data directly from autistic people. Four face-to-face and 2 online (text) focus groups were conducted with 32 autistic adults (19 female, 8 male, and 5 other), aged 23–64 who were able to express their internal experiences in words. They articulate in detail the actions they have difficulty with, what makes it easier or harder to act, and the impact on their lives. Thematic analysis of the transcripts found four overarching themes: descriptions of inertia, scaffolding to support action, the influence of wellbeing, and the impact on day-to-day activities. Participants described difficulty starting, stopping and changing activities that was not within their conscious control. While difficulty with planning was common, a subset of participants described a profound impairment in initiating even simple actions more suggestive of a movement disorder. Prompting and compatible activity in the environment promoted action, while mental health difficulties and stress exacerbated difficulties. Inertia had pervasive effects on participants’ day-to-day activities and wellbeing. This overdue research opens the door to many areas of further investigation to better understand autistic inertia and effective support strategies.

Event-Based Prospective Memory Deficit in Children with ADHD: Underlying Cognitive Factors and Association with Symptoms

Event-based prospective memory (PM) was investigated in children with Attention deficit/hyperactivity disorder (ADHD), using a novel experimental procedure to evaluate the role of working memory (WM) load, attentional focus, and reward sensitivity. The study included 24 children with ADHD and 23 typically-developing controls. The experimental paradigm comprised one baseline condition (BC), only including an ongoing task, and four PM conditions, varying for targets: 1 Target (1T), 4 Targets (4T), Unfocal (UN), and Reward (RE). Children with ADHD were slower than controls on all PM tasks and less accurate on both ongoing and PM tasks on the 4T and UN conditions. Within the ADHD group, the accuracy in the RE condition did not differ from BC. A significant relationship between ADHD-related symptoms and reduced accuracy/higher speed in PM conditions (PM and ongoing trials), but not in BC, was detected. Our data provide insight on the adverse role of WM load and attentional focus and the positive influence of reward in the PM performance of children with ADHD. Moreover, the relation between PM and ADHD symptoms paves the road for PM as a promising neuropsychological marker for ADHD diagnosis and intervention.

Event-, Time- and Activity-Based Prospective Memory in Children with ADHD

We examined prospective memory (PM) function in children with attention deficit hyperactivity disorder (ADHD). A group of 28 children with ADHD and 28 typically developing children completed event-, time- and activity-based PM tasks and attention tests. ADHD children had impaired attention but intact PM performance. Both groups performed best in activity-based PM tasks, followed by event-based PM tasks, and performed worst in time-based PM tasks. ADHD children had lower ongoing task performance in the event-based PM task. The findings indicate that children with ADHD may have an intact PM, but this may be at the cost of ongoing task performance.

Prospective Memory in Adolescents with Autism: A Preliminary Study of the Impact of Memory Load

We evaluated event-based prospective memory (EBPM) in adolescents with Autism, varying the load of the to-be-performed intentions. We included measures of inhibition, working memory and binding. Results showed that increasing the retrospective memory load reduced performance in controls. In Autism, adolescents were impaired in the low load condition with normal performance for the ongoing task, with the reverse pattern in the high load condition. EBPM may be impacted in Autism due to difficulty to process ongoing and EBPM tasks simultaneously possibly because of restricted inhibitory control.

Do importance instructions improve time-based prospective remembering in autism spectrum conditions?

This study explored the impact of motivation on the memory for delayed intentions (so-called, prospective memory, PM) in autistic individuals. Specifically, we were interested in the effects of personal (i.e., receiving a reward) as compared to social motivation (i.e., performing a favour for someone). Given the well-established theory of mind deficits in autism, we expected autistic individuals to benefit more strongly from personal than social importance manipulations, whereas the opposite pattern was predicted for controls. Sixty-one adolescents with autism and 61 typically developing adolescents participated, with each group distributed equally to one of the three motivation conditions of standard, social and personal reward. Participants worked on a 2-back picture-based ongoing task in which a time-based PM task was embedded. A mixed 2 (Group) x 3 (Motivation condition) analysis of covariance with age, verbal and non-verbal abilities as covariates and correct PM responses as dependent variable indicated solely a main effect of group, with controls outperforming the autism group. In contrast to our expectations, there was no main effect of condition, no significant interaction, and none of the covariates had any significant impact. However, further planned analyses revealed that controls only outperformed autistic individuals in the personal reward condition. Controls performed significantly best when a personal reward was promised, whereas there were no significant differences between the motivation conditions for autistic individuals. Findings are discussed in terms of underlying processes.

Prospective memory (partially) mediates the link between ADHD symptoms and procrastination

Individuals with attention deficit hyperactivity disorder (ADHD) often show poor planning and poor organization of tasks and activities which has been related to reduced memory for delayed intentions (prospective memory) and procrastination-in addition to other cognitive or motivational factors. This study set out to bring the fields of prospective memory and procrastination research together and to explore possible relations between the two constructs in ADHD. Twenty-nine adults with ADHD and 24 healthy controls performed several laboratory-based and real-life prospective memory tasks and filled in questionnaires measuring their symptom severity and procrastination behaviour. Overall, individuals' with ADHD showed clear deficits in everyday prospective memory performance. Individuals with ADHD recalled and executed less of their own real-life intentions. Moreover, there were clear links between everyday prospective memory performance and reported procrastination behaviour, and everyday prospective memory performance mediated the link between ADHD symptoms and procrastination behaviour.

Reinforcing the prospective remembering of children with autism spectrum disorder

Prospective memory is remembering to carry out a behavior on a particular occasion or at a specific time in the future. This form of remembering is critical for the daily functioning of children with autism spectrum disorder (ASD) and their functional independence from caregivers. We used a single-subject design to investigate whether reinforcement increased the accuracy of prospective remembering in the context of a computerized board game, Virtual Week, of four 6- to 7-year-old children diagnosed with ASD. Reinforcement increased accuracy for all participants compared to baseline performance and effects were maintained after reinforcement was discontinued for three of four children. This is the first study of which we are aware to use a reinforcement-based behavioral intervention to improve the prospective remembering of children with ASD. Limitations and areas for future research are discussed.

Do Inhibitory Control Demands Affect Event-Based Prospective Memory Performance in ADHD?

OBJECTIVE

Empirical evidence on prospective memory (PM) in ADHD is inconsistent. Differential findings have been related to differential executive control demands. This study aimed at exploring the impact of inhibitory control on event-based PM performance in ADHD.

METHOD

Eighteen adults with ADHD and 18 controls performed a word categorization task with an embedded event-based PM task. In addition, participants performed an acoustically presented task that put either low or high loads on inhibitory control processes.

RESULTS

Inhibitory load did not differentially affect PM performance: Across both inhibitory load conditions, individuals with ADHD showed reduced PM performance when compared with controls. Moreover, inhibitory load did not influence PM performance across both groups.

CONCLUSION

Possibly, full inhibitory control resources are not necessary during the entire duration of an event-based PM task, but may suffice to be employed after cue detection when needing to interrupt the ongoing task. (J. of Att. Dis. 2019; 23(1) 51-56).

Prospective memory in children with attention deficit hyperactivity disorder: a review

OBJECTIVE

The objective of the paper is to synthesize the research on prospective memory (PM) in children with attention-deficit/hyperactivity disorder (ADHD).

METHOD

Research on PM and ADHD in youth was synthesized according to the PRISMA guidelines and a summary of the types of PM deficits typically seen in these children, as well as the methods currently available to assess and treat these deficits is provided. Suggestions on ways to better manage PM deficits in children's everyday lives are also discussed.

RESULTS

Six studies have investigated PM in children with ADHD. The majority of these studies found a deficit in time-based PM, but not event-based PM. The mechanisms underlying this deficit, however, are still unknown. There are currently no specific measures available to clinically assess PM in children and there are no specific evidence-based interventions available that specifically target PM deficits in children with ADHD.

CONCLUSION

Remediation strategies aimed at compensating for these PM deficits in daily life may be most useful. Nevertheless, more research is necessary to better understand PM in children with ADHD.

A Meta-Analysis and Critical Review of Prospective Memory in Autism Spectrum Disorder

Prospective memory (PM) is the ability to remember to carry out a planned intention at an appropriate moment in the future. Research on PM in ASD has produced mixed results. We aimed to establish the extent to which two types of PM (event-based/time-based) are impaired in ASD. In part 1, a meta-analysis of all existing studies indicates a large impairment of time-based, but only a small impairment of event-based PM in ASD. In Part 2, a critical review concludes that time-based PM appears diminished in ASD, in line with the meta-analysis, but that caution should be taken when interpreting event-based PM findings, given potential methodological limitations of several studies. Clinical implications and directions for future research are discussed.

The Sequential Binge, a New Therapeutic Approach for Binge Eating: A Pilot Study

Background and Objectives

A sizeable proportion of patients experiencing binge eating do not respond to cognitive behavioral therapy (CBT). We present the sequential binge (SB), a new behavioral intervention that complements CBT, and preliminary results of its effects. SB breaks up the binge into repeated identical sequences of eating separated by incremental pauses. This pattern of ingestion aims at facilitating boredom toward the ingested foods and at turning cognitive control away from binge food restriction. SB is hypothesized to reduce food intake during the binge and the number of daily binges.

Methods

Prospective pilot study. Fifteen binging patients with previous unsuccessful intensive CBT were given SB as an adjunct to their treatment and were followed up for 16 weeks from admission. All patients were reassessed 47 weeks on average after discharge.

Results

SB was associated with a 44% relative reduction in the planned food intake (p<0.001), a longer consecutive binge refractory period compared to regular binges (median: 48 hours versus 4 hours, p = 0.002) and an average relative reduction by 26% of binge number the day after each SB (p = 0.004). 47% of patients reached binge abstinence for four consecutive weeks 16 weeks after the first SB.

Conclusion

This case series shows promising evidence for the use of SB in patients with refractory binge eating. Further evaluation in a prospective randomized controlled trial would be justified.

The role of interstimulus interval and "Stimulus-type" in prepotent response inhibition abilities in people with ASD: A quantitative and qualitative review

Autism spectrum disorders (ASD) are associated with prepotent response inhibition difficulties. However, the large variation between studies suggests that understudied factors, such as interstimulus interval (ISI) and "stimulus-type" (both hypothesized proxies of stressors influencing arousal), might influence the inhibitory abilities of people with ASD. Using meta-analysis, we tested whether differences in prepotent response inhibition between people with and without ASD was influenced by ISI. There was not enough variation in "stimulus-type" between the studies to include it as a moderator. Thirty-seven studies met inclusion criteria, with a combined sample size of 950 people with ASD and 966 typically developing controls. Additionally, a qualitative review including studies comparing a neutral and an arousing condition in one experiment was performed to examine whether fast ISI or specific arousing stimuli directly influence prepotent response inhibition. The meta-analysis indicated that ISI was not a relevant moderator. The qualitative review showed that ISI and "stimulus-type" had the same effect for both groups. Although all studies regarding ISI indicated that fast ISI worsened performance, different types of stimuli had either a positive or a negative influence. This could suggest that distinctive stimuli might affect arousal differently. While we replicated the inhibition difficulties in people with ASD (g = .51), our results do not show strong ASD-specific effects of ISI or "stimulus-type" on inhibition. Nonetheless, ISI and "stimulus-type" do seem to influence performance. Future research focusing on potential underlying factors (e.g., baseline physiological arousal) is needed to examine why this is the case. Autism Res 2016, 9: 1124-1141. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.

Event-based prospective memory in mildly and severely autistic children

BACKGROUND

There is a growing body of research into the development of prospective memory (PM) in typically developing children but research is limited in autistic children (Aut) and rarely includes children with more severe symptoms.

AIMS

This study is the first to specifically compare event-based PM in severely autistic children to mildly autistic and typically developing children.

METHODS AND PROCEDURES

Fourteen mildly autistic children and 14 severely autistic children, aged 5-13 years, were matched for educational attainment with 26 typically developing children aged 5-6 years. Three PM tasks and a retrospective memory task were administered.

OUTCOMES AND RESULTS

Results showed that severely autistic children performed less well than typically developing children on two PM tasks but mildly autistic children did not differ from either group. No group differences were found on the most motivating (a toy reward) task.

CONCLUSIONS AND IMPLICATIONS

The findings suggest naturalistic tasks and motivation are important factors in PM success in severely autistic children and highlights the need to consider the heterogeneity of autism and symptom severity in relation to performance on event-based PM tasks.

Prospective memory in adults with high-functioning autism spectrum disorders: exploring effects of implementation intentions and retrospective memory load

This study examined, for the first time, the impact of implementation intentions on prospective memory (PM) performance in adults with autism spectrum disorders (ASD) and further explored the role of retrospective memory for PM in ASD. PM was assessed with Virtual Week, a computerized game simulating upcoming everyday-life tasks. Twenty-seven adults with ASD and 27 age- and ability-matched controls were included. Half of the participants were instructed to form implementation intentions (i.e., encoding PM tasks in form of if-then statements), while the rest received simple PM instructions. Results provide first tentative evidence for beneficial effects of implementation intentions and PM tasks with low demands on retrospective memory for adults with ASD's PM. Overall, results point to the importance of planning and retrospective memory for successful prospective remembering in ASD.

Task dissociation in prospective memory performance in individuals with ADHD

OBJECTIVE

The present study investigated, for the first time, event- and time-based prospective memory (PM) in the same sample of adults with ADHD within one paradigm using parallel task constraints.

METHOD

A total of 25 individuals with ADHD and 25 matched neurotypical controls completed a computerized version of the Dresden Breakfast Task, which required participants to prepare breakfast following a set of rules and time restrictions.

RESULTS

Although groups did not differ in event-based PM, results demonstrated a large-sized impairment in individuals with ADHD in time-based PM.

CONCLUSION

Findings suggest a task-specific impairment in PM functioning and are discussed in an executive control framework of neurocognitive functioning in ADHD.

A Virtual Week study of prospective memory function in autism spectrum disorders

Prospective memory (PM) refers to the implementation of delayed intentions, a cognitive ability that plays a critical role in daily life because of its involvement in goal-directed behavior and consequently the development and maintenance of independence. Emerging evidence indicates that PM may be disrupted in autism spectrum disorders (ASDs), potentially contributing to the functional difficulties that characterize this group. However, the degree, nature, and specificity of ASD-related impairment remains poorly understood. In the current study, children between 8 and 12 years of age who were diagnosed with ASDs (n=30) were compared with typically developing children (n=30) on a child-appropriate version of the Virtual Week board game. This measure provides an opportunity to investigate the different sorts of PM failures that occur. The ASD group showed significant PM impairment on measures of time-based (but not event-based) prospective remembering. However, only a subtle difference emerged between regular and irregular PM tasks, and group differences were consistent across these tasks. Because regular and irregular tasks differentially load retrospective memory, these data imply that the PM difficulties seen in ASDs may primarily reflect a monitoring deficit and not an encoding and memory storage deficit. PM performance was poorer under conditions of high ongoing task absorption, but the magnitude of this effect did not vary as a function of group. In both groups, time-based (but not event-based) PM difficulties were associated with functional outcomes in daily life, but only an inconsistent association with executive control emerged.

Prepotent response inhibition and interference control in autism spectrum disorders: two meta-analyses

There is a substantial amount of data providing evidence for, but also against the hypothesis that individuals with autism spectrum disorders (ASD) encounter inhibitory control deficits. ASD is often associated with interference control deficits rather than prepotent response inhibition. Moreover, the developmental trajectory for these inhibitory control processes is hypothesized to differ in ASD as compared to typical development. In efforts to gain a more comprehensive perspective of inhibition in ASD, separate quantitative analysis for prepotent response inhibition studies and interference control studies were conducted. Together, these two meta-analyses included 41 studies with a combined sample size of 1,091 people with ASD (M age 14.8 years), and 1,306 typically developing (TD) controls (M age 13.8 years).The meta-analyses indicated that individuals with ASD show increased difficulties in prepotent response inhibition (effect size 0.55) and in interference control (effect size 0.31). In addition, age was a relevant moderator for prepotent response inhibition but not for interference control. Exploratory analyses revealed that when IQ was taken into account, heterogeneity considerably decreased among interference control studies but not among prepotent response inhibition. In contrast to the general belief, both prepotent response inhibition and interference control problems were observed in individuals with ASD. However, a large variation between studies was also found. Therefore, there remain factors beyond inhibition type, age, or IQ that significantly influence inhibitory control performance among individuals with ASD.

Time-based and event-based prospective memory in autism spectrum disorder: the roles of executive function and theory of mind, and time-estimation

Prospective memory (remembering to carry out an action in the future) has been studied relatively little in ASD. We explored time-based (carry out an action at a pre-specified time) and event-based (carry out an action upon the occurrence of a pre-specified event) prospective memory, as well as possible cognitive correlates, among 21 intellectually high-functioning children with ASD, and 21 age- and IQ-matched neurotypical comparison children. We found impaired time-based, but undiminished event-based, prospective memory among children with ASD. In the ASD group, time-based prospective memory performance was associated significantly with diminished theory of mind, but not with diminished cognitive flexibility. There was no evidence that time-estimation ability contributed to time-based prospective memory impairment in ASD.

Diminished time-based, but undiminished event-based, prospective memory among intellectually high-functioning adults with autism spectrum disorder: relation to working memory ability

Objective: Prospective memory (PM) is the ability to remember to carry out an intended action. Working memory is the ability to store information in mind while processing potentially distracting information. The few previous studies of PM in autism spectrum disorder (ASD) have yielded inconsistent findings. Studies of working memory ability in ASD have suggested a selective impairment of “visual working memory.” However, it remains unclear whether any such impairment is the result of diminished (domain-specific; visual/verbal) storage capacity or diminished (domain-general) processing capacity. We aim to clarify these issues and explore the relation between PM and working memory in ASD. Method: Seventeen adults with ASD and 17 age- and IQ-matched comparison participants completed experimental measures of both event-based (perform action x when event y occurs) and time-based (perform action a at time b) PM, plus a self-report measure of PM skills. Participants also completed a working memory test battery. Results: Participants with ASD self-reported diminished PM skill, and showed diminished performance on the time-based, but not event-based, PM task. On the working memory test battery, visual but not verbal storage capacity was diminished among participants with ASD, as was processing ability. Whereas visual storage was associated with event-based PM task performance among comparison participants, verbal storage was associated among ASD participants. Conclusions: ASD appears to involve a selective deficit in time-based PM and a selective difficulty with aspects of working memory that depend on the storage of visual information. However, event-based PM may be achieved through compensatory strategies in ASD.

Do adults with autism spectrum disorders compensate in naturalistic prospective memory tasks?

The present study is the first to directly compare event- and time-based prospective memory in Autism Spectrum Disorders (ASD) using a contextual task mirroring real life demands of prospective memory. Twenty-five individuals with ASD and 25 age- and ability-matched controls completed the Dresden Breakfast task which required participants to prepare breakfast following a set of rules and time restrictions. Overall, adults with ASD had less correct time- and event-based prospective memory responses in comparison to controls, which is consistent with previous research in children with ASD. Moreover, ASD participants completed fewer tasks, followed rules less closely, and monitored the elapsing time less closely than controls. Individuals with ASD seem not to be compensating in naturalistic prospective memory tasks.

Complex prospective memory in adults with attention deficit hyperactivity disorder

Objectives

Attention deficit hyperactivity disorder (ADHD) in adults has been associated with disturbances of attention and executive functions. Furthermore, impairments of verbal and figural retrospective memory were reported. However, little is known about the effects of ADHD on prospective memory, the execution of delayed intentions in the future.

Methods

The present study compared the performance of 45 adult patients with ADHD not treated with stimulant medication with the performance of 45 matched healthy individuals on a paradigm of complex prospective memory which measured task planning, plan recall, self-initiation and execution. Furthermore, the contribution of other cognitive functions to prospective memory functioning was assessed, including measures of attention, executive functions and memory.

Results

A large-scale impairment could be observed in task planning abilities in patients with ADHD. Only negligible to small effects were found for plan recall, self-initiation and execution. Inhibition was identified to contribute significantly to performance on task planning.

Conclusions

The present findings suggest that four cognitive components contribute to the performance of prospective memory. Impairments of prospective memory mainly emerged from deficient planning abilities in adults with ADHD. Implications on behavioral based intervention strategies are discussed.

Diagnosing autism in neurobiological research studies

Autism spectrum disorder (ASD) is by definition a complex and heterogeneous disorder. Variation in factors such as developmental level, language ability and IQ further complicate the presentation of symptoms. Clinical research and basic science must continue to inform each other's questions to help address the heterogeneity inherent to the disorder. This review uses a clinical perspective to outline the common tools and best practices for diagnosing and characterizing ASD in a research setting. We discuss considerations for classifying research populations, including language ability and IQ and examine the advantages and disadvantages of different psychometric measurements. Ultimately, the contribution of multiple sources of data representing different perspectives is crucial for interpreting and understanding the ASD phenotype.

Neuroeconomics of attention-deficit/hyperactivity disorder: differential influences of medial, dorsal, and ventral prefrontal brain networks on suboptimal decision making?

Psychiatric neuroeconomics offers an alternative approach to understanding mental disorders by studying the way disorder-related neurobiological alterations constrain economic agency, as revealed through decisions about choices between future goods. In this article, we apply this perspective to understand suboptimal decision making in attention-deficit/hyperactivity disorder (ADHD) by integrating recent advances in the neuroscience of decision making and studies of the pathophysiology of ADHD. We identify three brain networks as candidates for further study and develop specific hypotheses about how these could be implicated in ADHD. First, we postulate that altered patterns of connectivity within a network linking medial prefrontal cortex and posterior cingulate cortex (i.e., the default mode network) disrupts ordering of utilities, prospection about desired future states, setting of future goals, and implementation of aims. Second, we hypothesize that deficits in dorsal frontostriatal networks, including the dorsolateral prefrontal cortex and dorsal striatum, produce executive dysfunction-mediated impairments in the ability to compare outcome options and make choices. Third, we propose that dopaminergic dysregulation in a ventral frontostriatal network encompassing the orbitofrontal cortex, ventral striatum, and amygdala disrupts processing of cues of future utility, evaluation of experienced outcomes (feedback), and learning of associations between cues and outcomes. Finally, we extend this perspective to consider three contemporary themes in ADHD research.

The role of timing in testing nonverbal IQ in children with ASD

15 School-aged high functioning children on the autistic spectrum were compared with a neurotypical cohort on the WISC-III and the KABC-II, to determine the impact of the relatively more strict timing criteria of the former test on the evaluation of nonverbal intelligence. Significant group effects, showing lower performance by the ASD group were found for three of the five sub-tests for the WISC but not for the KABC, peaks and troughs were more evident for the WISC, and the evaluation of intellectual level was also markedly lower for ASD children on the WISC-III as opposed to the KABC-II. The results are discussed in terms of how speed of processing can impact on how children with ASD are 'matched' against neurotypical samples.