http://www.behavioralandbrainfunctions.com The latest research articles published by Behavioral and Brain Functions 2010-03-09T00:00:00Z This is an RSS newsfeed from BioMed Central It is intended to be used with an RSS reader. For more information about RSS newsfeeds from BioMed Central, visit http://www.biomedcentral.com/info/about/rss/ Autistic Spectrum Disorders (ASDs) are a set of complex developmental disabilities de-fined by impairment in social interaction and communication, as well as by restricted interests or repetitive behaviors. Neuroimaging studies have substantially advanced our understanding of the neural mechanisms that underlie the core symptoms of ASDs. Nevertheless, a number of chal-lenges still remain in the application of neuroimaging techniques to the study of ASDs. We re-view three major conceptual and methodological challenges that complicate the interpretation of findings from neuroimaging studies in ASDS, and that future imaging studies should address through improved designs. These include: (1) identification and implementation of tasks that more specifically target the neural processes of interest, while avoiding the confusion that the symptoms of ASD may impose on both the performance of the task and the detection of brain activations; (2) the inconsistency that disease heterogeneity in persons with ASD can generate on research findings, particularly heterogeneity of symptoms, symptom severity, differences in IQ, total brain volume, and psychiatric comorbidity; and (3) the problems with interpretation of find-ings from cross-sectional studies of persons with ASD across differing age groups. Failure to ad-dress these challenges will continue to hinder our ability to distinguish findings that outline the causes of ASDs from brain processes that represent downstream or compensatory responses to the presence of the disease. Here we propose strategies to address these issues: 1) the use of sim-ple and elementary tasks, that are easier to understand for autistic subjects; 2) the scanning of a more homogenus group of persons with ASDs, preferably at younger age; 3) the performance of longitudinal studies, that may provide more straight forward and reliable results. We believe that this would allow for a better understanding of both the central pathogenic processes and the compensatory responses in the brain of persons suffering from ASDs. http://www.behavioralandbrainfunctions.com/content/6/1/17 Luigi Mazzone Paolo Curatolo Behavioral and Brain Functions 2010, 6:17 2010-03-09T00:00:00Z doi:10.1186/1744-9081-6-17 Behavioral and Brain Functions 1744-9081 6 17 2010-03-09T00:00:00Z PDF Background: Active contraction leads to facilitation of motor responses evoked by transcranial magnetic stimulation (TMS). In small hand muscles, motor facilitation is known to be also influenced by the nature of the task. Recently, we showed that corticomotor facilitation was selectively enhanced when young participants actively discriminated tactile symbols with the tip of their index or little finger. This tactile-dependant motor facilitation reflected, for the large part, attentional influences associated with performing tactile discrimination, since execution of a concomitant distraction task abolished facilitation. In the present report, we extend these observations to examine the influence of age on the ability to produce extra motor facilitation when the hand is used for sensory exploration. Methods: Corticomotor excitability was tested in 16 healthy seniors (58-83 years) while they actively moved their right index finger over a surface under two task conditions. In the tactile discrimination (TD) condition, participants attended to the spatial location of two tactile symbols on the explored surface, while in the non discrimination (ND) condition, participants simply moved their finger over a blank surface. Changes in amplitude, in latency and in the silent period (SP) duration were measured from recordings of motor evoked potentials (MEP) in the right first dorsal interosseous muscle in response to TMS of the left motor cortex. Results: Healthy seniors exhibited widely varying levels of performance with the TD task, older age being associated with lower accuracy and vice-versa. Large inter-individual variations were also observed in terms of tactile-specific corticomotor facilitation. Regrouping seniors into higher (n = 6) and lower performance groups (n = 10) revealed a significant task by performance interaction. This latter interaction reflected differences between higher and lower performance groups; tactile-related facilitation being observed mainly in the former group. Latency measurements and SP durations were not affected by task conditions. Conclusions: The present findings provide further insights into the factors influencing task-dependant changes in corticomotor excitability in the context of aging. Our results, in particular, highlight the importance of adjusting task demands and controlling for attention when attempting to elicit task-specific motor facilitation in older persons engaged in fine manual actions. Such information could be critical in the future for planning interventions to re-educate or maintain hand function in the presence of neurological impairments. http://www.behavioralandbrainfunctions.com/content/6/1/16 Sabah Master Francois Tremblay Behavioral and Brain Functions 2010, 6:16 2010-03-05T00:00:00Z doi:10.1186/1744-9081-6-16 Behavioral and Brain Functions 1744-9081 6 16 2010-03-05T00:00:00Z XML Background: The intending process plays an important part to the successful completion of many daily activities. However, few researchers have paid attention to this issue. This study was set to investigate the time course and the electrophysiological evidence of the intending process with a cue-respond task. Methods: Event-related potentials (ERPs) were recorded while participants were performing different cued conditions (deceptive, truthful, and watch-only). The time course of intending process was analyzed through the different effect of the cue stimuli. Results: The P2 component, that appeared between 200 and 400 ms after the cue was onset, can be observed in the intended conditions (deceptive, truthful), but cannot be found in un-intended condition (watch-only). The mean amplitude in P2 between the truthful and deceptive conditions was consistent with previous studies. P2 was thought to be the reflection of the intention process. Conclusions: The results suggested that the intention process happened 200 to 400 ms after the cue stimuli was onset, and the P2 in the posterior scalp during this period could be a specific component that related with the process of intention. http://www.behavioralandbrainfunctions.com/content/6/1/15 Guangheng Dong Yanbo Hu Hui Zhou Behavioral and Brain Functions 2010, 6:15 2010-02-24T00:00:00Z doi:10.1186/1744-9081-6-15 Behavioral and Brain Functions 1744-9081 6 15 2010-02-24T00:00:00Z PDF Background: The N200 component of event related potentials (ERPs) is considered an index of monitoring error related responses. The aim of the present work was to study the effect of mismatch conditions on the subjects' responses in an auditory identification task and their relation to the N200 of stimulus-locked ERPs. Methods: An auditory identification task required to correctly map a horizontal slider onto an active frequency range by selecting a slider position that matched the stimulus tone in each trial. Fourteen healthy volunteers participated in the study and ERPs were recorded by 32 leads. Results: Results showed that the subjects' erroneous responses were equally distributed within trials, but were dependent on mismatch conditions, generated by large differences between the frequencies of the tones of consecutive trials. Erroneous trials showed a significantly greater negativity within the time window of 164-191 ms after stimulus, located mainly at the Cz and Fz electrodes. The LORETA solution showed that maximum activations, as well as maximum differences, were localized mainly at the frontal lobe. Conclusions: These findings suggest that the fronto-central N200 component, conceived an index of "reorientation of attention", represents a correlate of an error signal, being produced when representation of the actual response and the required response are compared. Furthermore the magnitude of the amplitude of the N200 rests on the relation between the present and the previous stimulus. http://www.behavioralandbrainfunctions.com/content/6/1/14 Irene Karanasiou Charalabos Papageorgiou Eleni Tsianaka Miltiades Kyprianou George Matsopoulos Errikos Ventouras Nikolaos Uzunoglu Behavioral and Brain Functions 2010, 6:14 2010-02-23T00:00:00Z doi:10.1186/1744-9081-6-14 Behavioral and Brain Functions 1744-9081 6 14 2010-02-23T00:00:00Z XML Background: The development of an evolutionarily grounded analogue magnitude representation linked to the parietal lobes is frequently thought to be a major factor in the arithmetic development of humans. We investigated the relationship between counting and the development of magnitude representation in children, assessing also children's knowledge of number symbols, their arithmetic fact retrieval, their verbal skills, and their numerical and verbal short-term memory. Methods: The magnitude representation was tested by a non-symbolic magnitude comparison task. We have perfected previous experimental designs measuring magnitude discrimination skills in 65 children kindergarten (4-7-year-olds) by controlling for several variables which were not controlled for in previous similar research. We also used a large number of trials which allowed for running a full factorial ANOVA including all relevant factors. Tests of verbal counting, of short term memory, of number knowledge, of problem solving abilities and of verbal fluency were administered and correlated with performance in the magnitude comparison task.Results and discussionVerbal counting knowledge and performance on simple arithmetic tests did not correlate with non-symbolic magnitude comparison at any age. Older children performed successfully on the number comparison task, showing behavioural patterns consistent with an analogue magnitude representation. In contrast, 4-year-olds were unable to discriminate number independently of task-irrelevant perceptual variables. Sensitivity to irrelevant perceptual features of the magnitude discrimination task was also affected by age, and correlated with memory, suggesting that more general cognitive abilities may play a role in performance in magnitude comparison tasks. Conclusion: We conclude that young children are not able to discriminate numerical magnitudes when co-varying physical magnitudes are methodically pitted against number. We propose, along with others, that a rather domain general magnitude representation provides the later basis for a specialized representation of numerical magnitudes. For this representational specialization, the acquisition of the concept of abstract numbers, together with the development of other cognitive abilities, is indispensable. http://www.behavioralandbrainfunctions.com/content/6/1/13 Fruzsina Soltesz Denes Szucs Livia Szucs Behavioral and Brain Functions 2010, 6:13 2010-02-18T00:00:00Z doi:10.1186/1744-9081-6-13 Behavioral and Brain Functions 1744-9081 6 13 2010-02-18T00:00:00Z XML Background: Change blindness refers to a failure to detect changes between consecutively presented images separated by, for example, a brief blank screen. As an explanation of change blindness, it has been suggested that our representations of the environment are sparse outside focal attention and even that changed features may not be represented at all. In order to find electrophysiological evidence of neural representations of changed features during change blindness, we recorded event-related potentials (ERPs) in adults in an oddball variant of the change blindness flicker paradigm. Methods: ERPs were recorded when subjects performed a change detection task in which the modified images were infrequently interspersed (p = .2) among the frequently (p = .8) presented unmodified images. Responses to modified and unmodified images were compared in the time window of 60-100 ms after stimulus onset. Results: ERPs to infrequent modified images were found to differ in amplitude from those to frequent unmodified images at the midline electrodes (Fz, Pz, Cz and Oz) at the latency of 60-100 ms even when subjects were unaware of changes (change blindness). Conclusions: The results suggest that the brain registers changes very rapidly, and that changed features in images are neurally represented even without participants' ability to report them. http://www.behavioralandbrainfunctions.com/content/6/1/12 Pessi Lyyra Jan Wikgren Piia Astikainen Behavioral and Brain Functions 2010, 6:12 2010-02-09T00:00:00Z doi:10.1186/1744-9081-6-12 Behavioral and Brain Functions 1744-9081 6 12 2010-02-09T00:00:00Z XML No description available http://www.behavioralandbrainfunctions.com/content/6/1/11 Lutz Jancke Pascale Sandmann Behavioral and Brain Functions 2010, 6:11 2010-02-08T00:00:00Z doi:10.1186/1744-9081-6-11 Behavioral and Brain Functions 1744-9081 6 11 2010-02-08T00:00:00Z XML Background: The assessment of social attribution skills in children can potentially identify and quantify developmental difficulties related to autism spectrum disorders and related conditions. However, relatively little is known about how these skills develop in typically developing children. Therefore the present study aimed to map the trajectory of social attribution skill acquisition in typically developing children from a young age. Methods: In the conventional social attribution task (SAT) participants ascribe feelings to moving shapes and describe their interaction in social terms. However, this format requires that participants understand both, that an inanimate shape is symbolic, and that its action is social in nature. This may be challenging for young children, and may be a potential confounder in studies of children with developmental disorders. Therefore we developed a modified SAT (mSAT) using animate figures (e.g. animals) to simplify the task. We used the SAT and mSAT to examine social attribution skill development in 154 healthy children (76 boys, 78 girls), ranging in age from 6 to 13 years and investigated the relationship between social attribution ability and executive function. Results: The mSAT revealed a steady improvement in social attribution skills from the age of 6 years, and a significant advantage for girls compared to boys. In contrast, children under the age of 9 years performed at baseline on the conventional format and there were no gender differences apparent. Performance on neither task correlated with executive function after controlling for age and verbal IQ, suggesting that social attribution ability is independent of cognitive functioning. The present findings indicate that the mSAT is a sensitive measure of social attribution skills from a young age. This should be carefully considered when choosing assessments for young children and those with developmental disorders. http://www.behavioralandbrainfunctions.com/content/6/1/10 Zhouyi Hu Raymond Chan Grainne McAlonan Behavioral and Brain Functions 2010, 6:10 2010-02-03T00:00:00Z doi:10.1186/1744-9081-6-10 Behavioral and Brain Functions 1744-9081 6 10 2010-02-03T00:00:00Z XML Background: Traditional peripheral biofeedback has grade A evidence for effectively treating migraines. Two newer forms of neurobiofeedback, EEG biofeedback and hemoencephalography biofeedback were combined with thermal handwarming biofeedback to treat 37 migraineurs in a clinical outpatient setting. Methods: 37 migraine patients underwent an average of 40 neurofeedback sessions combined with thermal biofeedback in an outpatient biofeedback clinic. All patients were on at least one type of medication for migraine; preventive, abortive or rescue. Patients kept daily headache diaries a minimum of two weeks prior to treatment and throughout treatment showing symptom frequency, severity, duration and medications used. Treatments were conducted an average of three times weekly over an average span of 6 months. Headache diaries were examined after treatment and a formal interview was conducted. After an average of 14.5 months following treatment, a formal interview was conducted in order to ascertain duration of treatment effects. Results: Of the 37 migraine patients treated, 26 patients or 70% experienced at least a 50% reduction in the frequency of their headaches which was sustained on average 14.5 months after treatments were discontinued. Conclusions: All combined neuro and biofeedback interventions were effective in reducing the frequency of migraines with clients using medication resulting in a more favorable outcome (70% experiencing at least a 50% reduction in headaches) than just medications alone (50% experience a 50% reduction) and that the effect size of our study involving three different types of biofeedback for migraine (1.09) was more robust than effect size of combined studies on thermal biofeedback alone for migraine (.5). These non-invasive interventions may show promise for treating treatment-refractory migraine and for preventing the progression from episodic to chronic migraine. http://www.behavioralandbrainfunctions.com/content/6/1/9 Deborah Stokes Martha Lappin Behavioral and Brain Functions 2010, 6:9 2010-02-02T00:00:00Z doi:10.1186/1744-9081-6-9 Behavioral and Brain Functions 1744-9081 6 9 2010-02-02T00:00:00Z XML Background: The aim of this study was to investigate the effects of a massed compared to a distributed practice upon visuomotor learning as well as upon the regional oscillatory activity in the sensorimotor cortex. Methods: A continuous visuomotor tracking task was used to assess visuomotor learning; the underlying neuronal correlates were measured by means of EEG. The massed practice group completed a continuous training of 60 minutes, while the distributed practice group completed four 15 minutes practice blocks separated by rest intervals. Results: While the massed and the distributed practice group did not differ in performance, effects of practice distribution were evident in the regional oscillatory activity. In the course of practice, the massed training group showed a higher task-related theta power and a strong task-related power decrease in the upper alpha frequency over the sensorimotor cortex compared to the distributed practice group. Conclusions: These differences in the regional oscillatory activity indicate a higher cognitive effort and higher attention demands in the massed practice group. The results of this study support the hypothesis, that a distributed practice is superior to a massed practice in visuomotor learning. http://www.behavioralandbrainfunctions.com/content/6/1/8 Bettina Studer Susan Koeneke Julia Blum Lutz Jancke Behavioral and Brain Functions 2010, 6:8 2010-01-22T00:00:00Z doi:10.1186/1744-9081-6-8 Behavioral and Brain Functions 1744-9081 6 8 2010-01-22T00:00:00Z XML