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.     

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.     

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.     

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.     

Phonological similarity effects in simple and complex span tasks

Three experiments were conducted to examine the effect of phonological similarity in simple and complex memory span tasks. In Experiment 1, participants performed either a simple or a complex span task, and the memoranda within lists were either phonologically similar or distinct. Phonologically similar lists consisted of words that rhymed.The simple span task was word span. There were two complex span tasks; one was the original reading span task, and the other was a variant of reading span in which all the sentences within a list were contextually related. The classic phonological similarity decrement was observed in word span. In contrast, phonological similarity facilitation was observed in both versions of reading span. This facilitation effect was further investigated in Experiment 2 using two new versions of reading span. In Experiment 2, the sentences in reading span were either short or long, and the memoranda were presented separately from, and were unrelated to, the sentences. Again, words within phonologically similar lists rhymed, and again, facilitation was observed. In Experiment 3, phonological similarity was operationalized in terms of feature overlap, rather than rhyme. The classic phonological similarity decrement was still observed in word span, but facilitation was not observed in complex span. The results suggest that phonological similarity, when operationalized using words that rhyme, serves as a list retrieval cue and that complex span tasks are more dependent on cue-driven memory retrieval mechanisms than are simple span tasks.     

Extending the simultaneous-sequential paradigm to measure perceptual capacity for features and words

In perception, divided attention refers to conditions in which multiple stimuli are relevant to an observer. To measure the effect of divided attention in terms of perceptual capacity, we introduce an extension of the simultaneous-sequential paradigm. The extension makes predictions for fixed-capacity models as well as for unlimited-capacity models. We apply this paradigm to two example tasks, contrast discrimination and word categorization, and find dramatically different effects of divided attention. Contrast discrimination has unlimited capacity, consistent with independent, parallel processing. Word categorization has a nearly fixed capacity, consistent with either serial processing or fixed-capacity, parallel processing. We argue that these measures of perceptual capacity rely on relatively few assumptions compared to most alternative measures.     

Affect in the aftermath: how goal pursuit influences implicit evaluations

Previous research has shown that the activation of a goal leads to more implicit positivity toward goal-relevant stimuli. We examined how the actual pursuit of a goal influences subsequent implicit positivity toward such stimuli. Participants were consciously or non-consciously primed with a goal, or not, and then completed a goal-relevant task on which they succeeded or failed. We then measured their goal-relevant implicit attitudes. Those who were primed with the goal (consciously or non-consciously) and experienced success exhibited more implicit positivity toward the goal, compared with the no-goal condition. Experiencing failure in the goal priming conditions reduced implicit positivity toward the goal, indicating disengagement from the goal. We discuss the theoretical implications for understanding the role of implicit attitudes in self-regulation.     

Libertarian Free Will and the Physical Indeterminism Luck Objection

Libertarian free will is, roughly, the view that agents (or, agent-involving events) cause actions to occur or not occur: Maddy’s decision to get a beer causes her to get up off her comfortable couch to get a beer, though she almost chose not to get up. Libertarian free will notoriously faces the luck objection, according to which agential states do not determine whether an action occurs or not, so it is beyond the control of the agent, hence lucky, whether an action occurs or not: Maddy’s reasons for getting beer in equipoise with her reasons to remain in her comfortable seat do not determine that she will get up or stay seated, so it seems beyond her control, hence lucky, that she gets up. In this paper I consider a sub-set of the luck objection called the Physical Indeterminism Luck Objection, according to which indeterministic physical processes cause actions to occur or not, and agent’s lack control over these indeterministic physical processes, so agent’s lack control over, hence it is lucky, whether action occurs or not. After motivating the physical indeterminism luck objection, I consider responses from three recent event-causal libertarian models, and conclude that they fail to overcome the problem, though one promising avenue is opened up.

This paper is divided into six parts. In Section One, I minimally define libertarian free will as accepting agential indeterminism, which is the conjunction of indeterminism and agential causation, where agential indeterminism occurs when an agent’s reasons, efforts or character indeterministically cause actions. In Sections Two and Three I outline the physical indeterminism luck objection to libertarian free will, which states that sub-agential physical processes in the brain indeterministically cause actions to occur, and agents lack control over these indeterministic physical causes, so agent’s lack control over whether their actions occur. If agent’s lack control over whether actions occur, the occurrence of these actions is lucky, where this luck jeopardizes free will and moral responsibility. In Sections Four through Six I consider three recent libertarian responses to this objection—Mark Balaguer in Section Four, Chris Franklin in Section Five, and Robert Kane in Section Six. I conclude that none of these models satisfactorily overcomes the physical indeterminism luck objection, though one interpretation of Kane yields a promising avenue of reply.