How the brain processes causal inferences in text

Abstract— Theoretical models of text processing, such as the construction-integration framework, pose fundamental questions about causal inference making that are not easily addressed by behavioral studies. In particular, a common result is that causal relatedness has a different effect on text reading times than on memory for the text: Whereas reading times increase linearly as causal relatedness decreases, memory for the text is best for events that are related by a moderate degree of causal relatedness and is poorer for events with low and high relatedness. Our functional magnetic resonance imaging study of the processing of two-sentence passages that varied in their degree of causal relatedness suggests that the inference process can be analyzed into two components, generation and integration, that are subserved by two large-scale cortical networks (a reasoning system in dorsolateral prefrontal cortex and the right-hemisphere language areas). These two cortical networks, which are distinguishable from the classical left-hemisphere language areas, approximately correspond to the two functional relations observed in the behavioral results.     

Differential reinstatement predicted by preextinction response rate

Reinstatement refers to the recovery of previously extinguished responding by the responseindependent delivery of a stimulus that was a reinforcer in training. Two experiments were conducted to examine relative reinstatement following the training of differential preextinction response rates, either with equal (Experiment 1) or unequal (Experiment 2) preextinction reinforcement rates. In Experiment 1, each of 3 pigeons first pecked at relatively high rates in the tandem variable-time 117-sec fixed-interval 3-sec component of a multiple schedule and at lower rates in a separate tandem variableinterval 117-sec fixed-time 3-sec component. Reinforcement rates were equal between components. Pecking then was extinguished in each component, before being reinstated under a multiple variabletime 120-sec variable-time 120-sec schedule. Greater reinstatement occurred in the component previously correlated with higher rates of pecking. In Experiment 2, in an initial condition, the mean rate of lever pressing for one group of 8 rats was significantly higher under a fixed-ratio 3 schedule than for another group of 8 rats under a fixed-ratio 1 schedule. Mean reinforcement rate was significantly higher for the group exposed to the fixed-ratio 1 schedule. For each group, lever pressing then was extinguished, before being reinstated under a variable-time 30-sec schedule. Significantly greater mean reinstatement occurred for the group previously exposed to the fixed-ratio 3 schedule. These results suggest that differential reinstatement may be predicted by preextinction response rate, perhaps independently of preextinction reinforcement rate.     

Religious obsessions and compulsions in a non-clinical sample: the Penn Inventory of Scrupulosity (PIOS)

The present investigation reports on the development and psychometric evaluation of the Penn Inventory of Scrupulosity (PIOS), a 19-item self-report scale measuring religious obsessive-compulsive symptoms. Factor analysis yielded a two factor solution with the first subscale measuring fears about having committed sin, and the second measuring fears concerning punishment from God. Using a sample of college students, the PIOS was shown to be internally consistent and possess good convergent and discriminant validity. Highly devout participants evidenced higher scores on both PIOS subscales, but devout Jews evidenced fewer fears of sin and punishment from God compared to devout Protestants or Catholics. The PIOS has utility both as a research and clinical tool.     

Effects of reinforcer magnitude on responding under differential-reinforcement-of-low-rate schedules of rats and pigeons

Experiment I investigated the effects of reinforcer magnitude on differential-reinforcement-of-low-rate (DRL) schedule performance in three phases. In Phase 1, two groups of rats (n = 6 and 5) responded under a DRI. 72-s schedule with reinforcer magnitudes of either 30 or 300 microl of water. After acquisition, the water amounts were reversed for each rat. In Phase 2, the effects of the same reinforcer magnitudes on DRL 18-s schedule performance were examined across conditions. In Phase 3, each rat responded unider a DR1. 18-s schedule in which the water amotnts alternated between 30 and 300 microl daily. Throughout each phase of Experiment 1, the larger reinforcer magnitude resulted in higher response rates and lower reinforcement rates. The peak of the interresponse-time distributions was at a lower value tinder the larger reinforcer magnitude. In Experiment 2, 3 pigeons responded under a DRL 20-s schedule in which reinforcer magnitude (1-s or 6-s access to grain) varied iron session to session. Higher response rates and lower reinforcement rates occurred tinder the longer hopper duration. These results demonstrate that larger reinforcer magnitudes engender less efficient DRL schedule performance in both rats and pigeons, and when reinforcer magnitude was held constant between sessions or was varied daily. The present results are consistent with previous research demonstrating a decrease in efficiency as a function of increased reinforcer magnituide tinder procedures that require a period of time without a specified response. These findings also support the claim that DRI. schedule performance is not governed solely by a timing process.     

Modeling caregiver adaptation over time: the longitudinal impact of behavior problems

Although cross-sectional research has established the link between care demands and various indicators of caregiver adaptation, few studies have examined the impact of care recipients' problematic behavior over time. The present analysis determines the importance of behavior problems when predicting rates of change in subjective stressors (role overload and role captivity) and depression. Using 4-wave longitudinal data (N = 137) on dementia caregivers, the authors fit individual growth curve models for care demands (i.e., behavior problems, activities of daily living dependencies, and cognitive impairment), subjective stressors, and depression. Subsequent structural equation models found that increases in behavior problems were most likely to predict increases in role overload. The findings emphasize the deleterious long-term impact of behavior problems on individuals' emotional adaptation to caregiving.     

The structure of the self-concept and its relation to psychological adjustment

Research on the relation between the structure of the self-concept and psychological adjustment has produced seemingly inconsistent findings. Some research suggests that greater pluralism in self-concept structure enhances adjustment, whereas other research suggests that greater unity in the structure enhances adjustment. Four studies examined the relations among measures of self-concept structure and their relations with adjustment. The measures of self-concept structure included two that we viewed as reflecting self-concept pluralism (self-complexity and self-concept compartmentalization) and four that we viewed as reflecting self-concept unity (self-concept differentiation, self-concept clarity, self-discrepancies, and the average correlation among participants' self-aspects). The measures of self-concept pluralism were unrelated to one another, were unrelated to the measures of self-concept unity, and were unrelated to the measures of adjustment. The measures of self-concept unity were moderately related to one another and were moderately related to the measures of adjustment.     

Brain imaging of tongue-twister sentence comprehension: twisting the tongue and the brain

This study used fMRI to investigate the neural basis of the tongue-twister effect in a sentence comprehension task. Participants silently read sentences equated for the syntactic structure and the lexical frequency of the constituent words, but differing in the proportion of words that shared similar initial phonemes. The manipulation affected not only the reading times and comprehension performance, but also the amount of activation seen in a number of language-related cortical areas. The effect was not restricted to cortical areas known to be involved in articulatory speech programming or rehearsal processes (the inferior frontal gyrus and anterior insula), but also extended to areas associated with other aspects of language processing (inferior parietal cortex) associated with phonological processing and storage.     

Ambiguity in the brain: what brain imaging reveals about the processing of syntactically ambiguous sentences

Two fMRI studies investigated the time course and amplitude of brain activity in language-related areas during the processing of syntactically ambiguous sentences. In Experiment 1, higher levels of activation were found during the reading of unpreferred syntactic structures as well as more complex structures. In Experiments 2A and 2B higher levels of brain activation were found for ambiguous sentences compared with unambiguous sentences matched for syntactic complexity, even when the ambiguities were resolved in favor of the preferred syntactic construction (despite the absence of this difference in previous reading time results). Although results can be reconciled with either serial or parallel models of sentence parsing, they arguably fit better into the parallel framework. Serial models can admittedly be made consistent but only by including a parallel component. The fMRI data indicate the involvement of a parallel component in syntactic parsing that might be either a selection mechanism or a construction of multiple parses.     

A Coalgebraic View of Heyting Duality

We give a coalgebraic view of the restricted Priestley duality between Heyting algebras and Heyting spaces. More precisely, we show that the category of Heyting spaces is isomorphic to a full subcategory of the category of all -coalgebras, based on Boolean spaces, where is the functor which maps a Boolean space to its hyperspace of nonempty closed subsets. As an appendix, we include a proof of the characterization of Heyting spaces and the morphisms between them.