Apathy in frontotemporal dementia: behavioral and neuroimaging correlates

We investigated the occurrence of goal-directed motivational change in the form of apathy in patients with frontotemporal dementia (FTD), particularly those with behavioral variant social and executive deficits (bvFTD). Standardized behavioral inventory was employed to survey and compare apathy ratings from patients and caregivers. In cases of bvFTD, apathy ratings were further related to measures of social cognition, executive function, and atrophy on brain MRI. Results indicated that caregivers rated bvFTD patients as having significantly elevated apathy scores though patient self-ratings were normal. Caregiver and self-ratings of FTD samples with progressive nonfluent aphasia and semantic dementia did not differ from healthy controls and their informants. In the bvFTD sample, caregiver apathy scores were not correlated with general cognitive screening or depression scores, but were significantly correlated with social cognition and executive function measures. Voxel-based morphometry revealed that apathy ratings in bvFTD were related to prominent atrophy in the right caudate (including the ventral striatum), the right temporo-parietal junction, right posterior inferior and middle temporal gyri, and left frontal operculum- anterior insula region. Findings suggest that bvFTD is associated with a significant breakdown in goal-directed motivated behavior involving disruption of cortical-basal ganglia circuits that is also related to social and executive function deficits.     

Frequent false hearing by older adults: the role of age differences in metacognition

In two experiments testing age differences in the subjective experience of listening, which we call meta-audition, young and older adults were first trained to learn pairs of semantic associates. Following training, both groups were tested on identification of words presented in noise, with the critical manipulation being whether the target item was congruent, incongruent, or neutral with respect to prior training. Results of both experiments revealed that older adults compared to young adults were more prone to "false hearing," defined as mistaken high confidence in the accuracy of perception when a spoken word had been misperceived. These results were obtained even when performance was equated across age groups on control items by reducing the noise level for older adults. Such false hearing is shown to reflect older adults' heavier reliance on context. Findings suggest that older adults' greater ability to benefit from semantic context reflects their bias to respond consistently with the context, rather than their greater skill in using context. Procedures employed are unique in measuring the subjective experience of hearing as well as its accuracy. Both theoretical and applied implications of the findings are discussed. Convergence of results with those showing higher false memory, and false seeing are interpreted as showing that older adults are less able to constrain their processing in ways that are optimal for performance of a current task. That lessened constraint may be associated with decline in frontal-lobe functioning.     

A neural predictor of cultural popularity

We use neuroimaging to predict cultural popularity — something that is popular in the broadest sense and appeals to a large number of individuals. Neuroeconomic research suggests that activity in reward-related regions of the brain, notably the orbitofrontal cortex and ventral striatum, is predictive of future purchasing decisions, but it is unknown whether the neural signals of a small group of individuals are predictive of the purchasing decisions of the population at large. For neuroimaging to be useful as a measure of widespread popularity, these neural responses would have to generalize to a much larger population that is not the direct subject of the brain imaging itself. Here, we test the possibility of using functional magnetic resonance imaging (fMRI) to predict the relative popularity of a common good: music. We used fMRI to measure the brain responses of a relatively small group of adolescents while listening to songs of largely unknown artists. As a measure of popularity, the sales of these songs were totaled for the three years following scanning, and brain responses were then correlated with these “future” earnings. Although subjective likability of the songs was not predictive of sales, activity within the ventral striatum was significantly correlated with the number of units sold. These results suggest that the neural responses to goods are not only predictive of purchase decisions for those individuals actually scanned, but such responses generalize to the population at large and may be used to predict cultural popularity.     

Affording Emerging Adulthood: Parental Financial Assistance of their College-Aged Children

The purpose of this study was to examine parents’ attitudes about and patterns of providing financial assistance to their children during college, and how varying levels of parental financial support were related to children’s beliefs (e.g., perceptions of adulthood), behaviors (e.g., work hours, drinking, and drug use), and identity development. The sample consisted of 402 undergraduate students (62% women) recruited from four college sites across the United States (M age = 19.89), and one of their parents (310 mothers and 92 fathers). Using cluster analysis, results suggested four distinct approaches to parental financial involvement and found that emerging adults’ beliefs, behaviors, and identity development differed as a function of parents’ cluster membership. Discussion focuses on implications for emerging adult children whose parents endorse varying levels of financial involvement.     

Nitric oxide synthesis in the basolateral complex of the amygdala is required for the consolidation and expression of fear potentiated startle but not shock sensitization of the acoustic startle

Nitric oxide (NO) is synthesized as a result of N-methyl-d-asparate (NMDA) receptor activation, it acts as an retrograde neurotransmitter freely diffusing across cell membranes interacting with its targets in a non-synaptic manner. Consequently, NO has been described as an extension of NMDA receptor activation. The targets of NO include cellular components within the basolateral complex of the amygdala (BLA) that are necessary for the consolidation of conditioned fear as well as targets that can significantly modulate neurotransmission associated with its expression. Given that both are NMDA receptor associated processes, this implies that NO may be an important intermediary of NMDA receptor activation and both fear memory consolidation and expression. The current study sought to examine this using visual fear conditioning and fear potentiated startle. Three experiments were conducted, rats received intra-BLA microinfusions of the global nitric oxide synthase inhibitor l-NAME either prior to fear conditioning, or expression of learned fear. Furthermore, NO's ability to modulate a NMDA receptor independent fear process was assessed by microinfusing l-NAME into the BLA prior to examination of the shock sensitization of the acoustic startle affect. The results indicated that NO was, indeed, required for both the consolidation and expression of learned fear, whereas it was not required for NMDA independent shock enhanced startle responding. This study illustrates that NO plays a pivotal role in the examined NMDA associated fear processes.     

Negative triangles: simple geometric shapes convey emotional valence

It has been suggested that downward pointing triangles convey negative valence, perhaps because they mimic an underlying primitive feature present in negative facial expressions (Larson, Aronoff, and Stearns, 2007). Here, we test this proposition using a flanker interference paradigm in which participants indicated the valence of a central face target, presented between two adjacent distracters. Experiment 1 showed that, compared with face flankers, downward pointing triangles had little influence on responses to face targets. However, in Experiment 2, when attentional competition was increased between target and flankers, downward pointing triangles slowed responses to positively valenced face targets, and speeded them to negatively valenced targets, consistent with valence-based flanker compatibility effects. These findings provide converging evidence that simple geometric shapes may convey emotional valence.     

Young children overimitate in third-party contexts

The exhibition of actions that are causally unnecessary to the outcomes with which they are associated is a core feature of human cultural behavior. To enter into the world(s) of their cultural in-group, children must learn to assimilate such unnecessary actions into their own behavioral repertoire. Past research has established the habitual tendency of children to adopt the redundant actions of adults demonstrated directly to them. Here we document how young children will do so even when such actions are modeled to a third person regardless of whether children are presented with the test apparatus by the demonstrating, and assumedly expert, adult or by the observing, and assumedly naive, adult (Experiment 1), whether or not children had opportunity to discover how the apparatus works prior to modeling (Experiment 1), and whether or not children's attention was drawn to the demonstration while they were otherwise occupied (Experiment 2). These results emphasize human children's readiness to acquire behavior that is in keeping with what others do, regardless of the apparent efficiency of the actions employed, and in so doing to participate in cultural learning.     

Improving Working Memory in Children with Attention-Deficit/Hyperactivity Disorder: The Separate and Combined Effects of Incentives and Stimulant Medication

Working memory (WM) is considered a core deficit in Attention-Deficit/ Hyperactivity Disorder (ADHD), with numerous studies demonstrating impaired WM among children with ADHD. We tested the degree to which WM in children with ADHD was improved by performance-based incentives, an analog of behavioral intervention. In two studies, WM performance was assessed using a visuo-spatial n-back task. Study 1 compared children (ages 9-12?years) with ADHD-Combined type (n?=?24) to a group of typically developing (TD) children (n?=?32). Study 1 replicated WM deficits among children with ADHD. Incentives improved WM, particularly among children with ADHD. The provision of incentives reduced the ADHD-control group difference by approximately half but did not normalize WM. Study 2 examined the separate and combined effects of incentives and stimulant medication among 17 children with ADHD-Combined type. Both incentives and a moderate dose of long-acting methylphenidate (MPH; ~0.3?mg/kg t.i.d. equivalent) robustly improved WM relative to the no-incentive, placebo condition. The combination of incentives and medication improved WM significantly more than either incentives or MPH alone. These studies indicate that contingencies markedly improve WM among children with ADHD-Combined type, with effect sizes comparable to a moderate dose of stimulant medication. More broadly, this work calls attention to the role of motivation in studying cognitive deficits in ADHD and in testing multifactorial models of ADHD.     

A Review of Baum's Review of Conceptual Foundations of Radical Behaviorism

Baum expressed numerous concerns about my Conceptual Foundations of Radical Behaviorism in his review. If his review were an independent submission and I were an independent referee, I would recommend that his review be rejected and that he be encouraged to revise and resubmit, once he has studied the field a bit more and clarified for himself and journal readers several important matters. I outline two sets of concerns that he might usefully clarify in his revision: (a) the important contributions of B. F. Skinner to a book about radical behaviorism, and (b) the nature of private behavioral events. In particular, the methodological behaviorism inherent in Baum's position needs to be resolved.