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Emotional dysregulation in ADHD patients has become an important issue in recent years. Dysfunctions especially in brain regions related to emotional processing as well as psychophysiological reactions have been reported. This review includes functional MRI, event-related potentials as well as emotion-modulated startle studies in ADHD patients. It reflects a selective review of the authors with no claim of completeness. Changes in the processing of positive stimuli, with reduced brain activity in the amygdala, in the ventral striatum and reduced EEG potentials were found. The relevance of the observed dysregulation in emotional processing and psychophysiological reactions with regard to theoretical constructs of ADHD-specific emotional dysregulation versus comorbidity will be discussed.

Behavioral studies have found a striking decline in the processing of low-level motion in healthy aging whereas the processing of more relevant and familiar biological motion is relatively preserved. This functional magnetic resonance imaging (fMRI) study investigated the neural correlates of low-level radial motion processing and biological motion processing in 19 healthy older adults (age range 62–78 years) and in 19 younger adults (age range 20–30 years). Brain regions related to both types of motion stimuli were evaluated and the magnitude and time courses of activation in those regions of interest were calculated. Whole-brain comparisons showed increased temporal and frontal activation in the older group for low-level motion but no differences for biological motion. Time-course analyses in regions of interest known to be involved in both types of motion processing likewise did not reveal any age differences for biological motion. Our results show that low-level motion processing in healthy aging requires the recruitment of additional resources, whereas areas related to the processing of biological motion processing seem to be relatively preserved.

This study examined general deficits in positive stimuli evaluation in adults with Attention Deficit Hyperactivity Disorder (ADHD). We investigated the event-related potentials to positive, negative and neutral pictures in 32 adults with ADHD and 32 control subjects. For this study we measured 21 electrodes placed in accordance with the international 10-20 system and calculated the early posterior negativity (EPN), which physiologically is characterized by more negative values for emotional as compared to neutral stimuli. We found significantly reduced EPN values for the ADHD patients compared to the healthy controls, but only in the positive stimuli condition, without any significant differences in the negative stimuli condition. Our data indicate that ADHD patients show less reactivity to positive visual stimuli which might be relevant in the context of described dysfunctions of the motivational-reward system in ADHD.

ObjectiveSeveral studies report increased reward sensitivity towards food in overweight individuals. By contrast, data is inconclusive with respect to response inhibition in overweight individuals without binge eating disorder (BED). Hence, the latter was addressed in the present study in a group of overweight/obese females with and without BED and a normal-weight control group without eating disorders.MethodA group of women with BED (n = 29), a group of overweight women without BED (n = 33) and normal-weight females (n = 30) participated in a pictorial priming paradigm, with food items (relevant primes) and office utensils (neutral primes) and color blobs (neutral primes) as stimuli. Increased response priming effects (i.e. priming with switches between stimulus categories) were taken as indicators of deficient behavioral inhibition.ResultsPriming effects for neutral primes were moderate and comparable across all groups. However, primes associated with the food task set lead to increased priming effects in both overweight groups. But, effects were comparable for overweight/obese participants with and without BED.DiscussionResults suggest that early response inhibition in the context of food is impaired in overweight individuals compared to normal-weight individuals.

Background: Findings are mixed regarding the association of electroencephalographic (EEG) attentional bias measures and body weight, with few studies measuring food craving or intake and no study reporting oscillatory measures. Methods: EEG data were collected while 28 satiated adolescents (14 overweight/obese) viewed pictures of neutral, lowcalorie food, and high-calorie food stimuli and rated their desire to eat, before having access to high-calorie snacks. Results: Unlike normal-weight adolescents, overweight/obese participants showed similar P300 amplitudes for high-and low-calorie food, and strongest event-related alpha band desynchronization for low-calorie stimuli. P300 amplitudes and state craving for low-calorie food furthermore predicted snack intake in this group. Conclusions: The current research focus in overweight/obesity might need to be extended to include low-calorie food. While all participants showed an attentional bias for high-calorie food, it was the processing of low-calorie food which distinguished the two weight groups on measures of neural activity and which was associated with snack food intake in the overweight/obese group.

It is beyond controversy that in bimanual coordination tasks, parameter planning related to the movements of one hand influences the planning and execution of movements simultaneously performed with the other hand. A well-researched example of such bimanual interference is the finding that reaction times tend to be longer when preparing bimanual pointing movements with different amplitudes than for equal amplitude movements. Interestingly, these reaction time costs were found to increase when movement targets were cued symbolically (e.g., using letters) as compared to spatially. Therefore, it was suggested that interference may be primarily related to cue translation and response selection processes rather than resulting from cross-talk at the motor programming level. Here, we argue that spatial interference effects do not necessarily depend on the type of cues used but instead depend on the general task demands (difficulty). In two experiments we show that bimanual interference effects can (1) be abolished in symbolic cueing conditions when highly compatible cues placing minimal demands on response selection processes are used and (2) occur in direct/spatial cueing conditions when a secondary cognitively demanding, but movement-unrelated task is performed. Thus, our findings suggest that whether or not interference effects emerge during movement planning depends on the overall task difficulty and hence the resources available during movement preparation.