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Shifting motor actions from reflexively reacting to an environmental stimulus to predicting it allows for smooth synchronization of behavior with the outside world. This shift relies on the identification of patterns within the stimulus - knowing when a stimulus is predictable and when it is not - and launching motor actions accordingly. Failure to identify predictable stimuli results in movement delays whereas failure to recognize unpredictable stimuli results in early movements with incomplete information that can result in errors. Here we used a metronome task, combined with video-based eye-tracking, to quantify temporal predictive learning and performance to regularly paced visual targets at 5 different interstimulus intervals (ISIs). We compared these results to the random task where the timing of the target was randomized at each target step. We completed these tasks in female pediatric psychiatry patients (age range: 11-18 years) with borderline personality disorder (BPD) symptoms, with (n = 22) and without (n = 23) a comorbid attention-deficit hyperactivity disorder (ADHD) diagnosis, against controls (n = 35). Compared to controls, BPD and ADHD/BPD cohorts showed no differences in their predictive saccade performance to metronome targets, however, when targets were random ADHD/BPD participants made significantly more anticipatory saccades (i.e., guesses of target arrival). The ADHD/BPD group also significantly increased their blink rate and pupil size when initiating movements to predictable versus unpredictable targets, likely a reflection of increased neural effort for motor synchronization. BPD and ADHD/BPD groups showed increased sympathetic tone evidenced by larger pupil sizes than controls. Together, these results support normal temporal motor prediction in BPD with and without ADHD, reduced response inhibition in BPD with comorbid ADHD, and increased pupil sizes in BPD patients. Further these results emphasize the importance of controlling for comorbid ADHD when querying BPD pathology. [ABSTRACT FROM AUTHOR]

The capacity for inhibitory control is an important cognitive process that undergoes dynamic changes over the course of the lifespan. Robust characterization of this trajectory, considering age continuously and using flexible modeling techniques, is critical to advance our understanding of the neural mechanisms that differ in healthy aging and neurological disease. The interleaved pro/anti-saccade task (IPAST), in which pro- and anti-saccade trials are randomly interleaved within a block, provides a simple and sensitive means of assessing the neural circuitry underlying inhibitory control. We utilized IPAST data collected from a large cross-sectional cohort of normative participants (n = 604, 5–93 years of age), standardized pre-processing protocols, generalized additive modeling, and change point analysis to investigate the effect of age on saccade behavior and identify significant periods of change throughout the lifespan. Maturation of IPAST measures occurred throughout adolescence, while subsequent decline began as early as the mid-20s and continued into old age. Considering pro-saccade correct responses and anti-saccade direction errors made at express (short) and regular (long) latencies was crucial in differentiating developmental and aging processes. We additionally characterized the effect of age on voluntary override time, a novel measure describing the time at which voluntary processes begin to overcome automated processes on anti-saccade trials. Drawing on converging animal neurophysiology, human neuroimaging, and computational modeling literature, we propose potential frontal-parietal and frontal-striatal mechanisms that may mediate the behavioral changes revealed in our analysis. We liken the models presented here to "cognitive growth curves" which have important implications for improved detection of neurological disease states that emerge during vulnerable windows of developing and aging. [ABSTRACT FROM AUTHOR]

Impulsivity and emotional dysregulation are two core features of borderline personality disorder (BPD), and the neural mechanisms recruited during mixed-strategy interactions overlap with frontolimbic networks that have been implicated in BPD. We investigated strategic choice patterns during the classic two-player game, Matching Pennies, where the most efficient strategy is to choose each option randomly from trial-to-trial to avoid exploitation by one's opponent. Twenty-seven female adolescents with BPD (mean age: 16 years) and twenty-seven age-matched female controls (mean age: 16 years) participated in an experiment that explored the relationship between strategic choice behavior and impulsivity in both groups and emotional dysregulation in BPD. Relative to controls, BPD participants showed marginally fewer reinforcement learning biases, particularly decreased lose-shift biases, increased variability in reaction times (coefficient of variation; CV), and a greater percentage of anticipatory decisions. A subset of BPD participants with high levels of impulsivity showed higher overall reward rates, and greater modulation of reaction times by outcome, particularly following loss trials, relative to control and BPD participants with lower levels of impulsivity. Additionally, BPD participants with higher levels of emotional dysregulation showed marginally increased reward rate and increased entropy in choice patterns. Together, our preliminary results suggest that impulsivity and emotional dysregulation may contribute to variability in mixed-strategy decision-making in female adolescents with BPD. [ABSTRACT FROM AUTHOR]

When presented with a periodic stimulus, humans spontaneously adjust their movements from reacting to predicting the timing of its arrival, but little is known about how this sensorimotor adaptation changes across development. To investigate this, we analyzed saccade behavior in 114 healthy humans (ages 6-24 years) performing the visual metronome task, who were instructed to move their eyes in time with a visual target that alternated between two known locations at a fixed rate, and we compared their behavior to performance in a random task, where target onsets were randomized across five interstimulus intervals (ISIs) and thus the timing of appearance was unknown. Saccades initiated before registration of the visual target, thus in anticipation of its appearance, were labeled predictive [saccade reaction time (SRT),90ms] and saccades that were made in reaction to its appearance were labeled reactive (SRT.90ms). Eye-tracking behavior including saccadic metrics (e.g., peak velocity, amplitude), pupil size following saccade to target, and blink behavior all varied as a function of predicting or reacting to periodic targets. Compared with reactive saccades, predictive saccades had a lower peak velocity, a hypometric amplitude, smaller pupil size, and a reduced probability of blink occurrence before target appearance. The percentage of predictive and reactive saccades changed inversely from ages 8--16, at which they reached adult-levels of behavior. Differences in predictive saccades for fast and slow target rates are interpreted by differential maturation of cerebellar-thalamic-striatal pathways. [ABSTRACT FROM AUTHOR]

Abstract: Eye movement desensitization and reprocessing (EMDR), a form of psychotherapy for individuals with post‐traumatic stress disorder (PTSD), has long been a controversial topic, hampered in part by a lack of understanding of the neural mechanisms that contribute to its remedial effect. Here, we review current theories describing EMDR's potential neurobiological mechanisms of action involving working memory, interhemispheric communication, de‐arousal, and memory reconsolidation. We then discuss recent studies describing the temporal and spatial aspects of smooth pursuit and predictive saccades, which resemble those made during EMDR, and their neural correlates within the default mode network (DMN) and cerebellum. We hypothesize that if the production of bilateral predictive eye movements is supportive of DMN and cerebellum activation, then therapies that shift the brain towards this state correspondingly would benefit the processes regulated by these structures (i.e., memory retrieval, relaxation, and associative learning), all of which are essential components for PTSD recovery. We propose that the timing of sensory stimulation may be relevant to treatment effect and could be adapted across different patients depending on their baseline saccade metrics. Empirical data in support of this model are reviewed and experimental predictions are discussed. [ABSTRACT FROM AUTHOR]

Objective: [1] To highlight the effectiveness of multi-family psychoeducation group therapy (MFPGT) in children with mood or anxiety disorders; [2] to measure change in knowledge and awareness of mood and anxiety disorders in families and children; and [3] to compare the relative effectiveness of online compared to live MFPGT.Method: Participants included families of children (12 years or younger) referred with a mood or anxiety disorder to the Division of Child and Adolescent Psychiatry at Queen's University (n=16) who were on a waitlist to see a psychiatrist. Change was measured through questionnaires for all parents before and after the program. Using SPSS v22, comparisons between the online (n=6) and live (n=10) groups were made using the Mann-Whitney U test and within group comparisons were made using Wilcoxon signed-rank test.Results: The online and live education groups showed similar overall improvements in knowledge acquisition and expressed emotion in participating families. However, statistical significance must be interpreted with caution due to the small sample size.Conclusions: Online MFPGT may be an effective way to increase knowledge, provide resources and support and build on skills thus giving individuals more control and confidence when dealing with a mood or anxiety disorder while on a waitlist. MFPGT showed equal efficacy in live and online groups, indicating that the online program has the potential to be a more convenient and accessible program for families. More research is needed with a greater sample size. [ABSTRACT FROM AUTHOR]

Objective: [1] To highlight the effectiveness of multi-family psychoeducation group therapy (MFPGT) in children with mood or anxiety disorders; [2] to measure change in knowledge and awareness of mood and anxiety disorders in families and children; and [3] to compare the relative effectiveness of online compared to live MFPGT., Method: Participants included families of children (12 years or younger) referred with a mood or anxiety disorder to the Division of Child and Adolescent Psychiatry at Queen's University (n=16) who were on a waitlist to see a psychiatrist. Change was measured through questionnaires for all parents before and after the program. Using SPSS v22, comparisons between the online (n=6) and live (n=10) groups were made using the Mann-Whitney U test and within group comparisons were made using Wilcoxon signed-rank test., Results: The online and live education groups showed similar overall improvements in knowledge acquisition and expressed emotion in participating families. However, statistical significance must be interpreted with caution due to the small sample size., Conclusions: Online MFPGT may be an effective way to increase knowledge, provide resources and support and build on skills thus giving individuals more control and confidence when dealing with a mood or anxiety disorder while on a waitlist. MFPGT showed equal efficacy in live and online groups, indicating that the online program has the potential to be a more convenient and accessible program for families. More research is needed with a greater sample size.