Group-based reasons for action

This article endorses a familiar, albeit controversial, argument for the existence of group-based reasons for action, but then rejects two doctrines which other advocates of such reasons usually accept. One such doctrine is the willingness requirement, which says that a group-based reason exists only if (sufficient) other members of the group in question are willing to cooperate. Thus the paper argues that there is sometimes a reason, which derives from the rationality of some group action, to play one's part unilaterally in that group action. This seems implausible only because we tend wrongly to accept a second doctrine, monism about the unit of agency. Monism claims that, for any given deliberative problem, there is only one unit of agency to which reasons attach. If we are monists who believe in group-based reasons, the willingness requirement will seem necessary in order to avoid recklessness. We should reject monism, and if we do so we can recognise genuine conflict between individual-based and group-based reasons, and in doing so we can explain, without endorsing the willingness requirement, why we should not act recklessly.     

ENSEMBLE RECORDINGS IN AWAKE RATS: ACHIEVING BEHAVIORAL REGULARITY DURING MULTIMODAL STIMULUS PROCESSING AND DISCRIMINATIVE LEARNING

To meet an increasing need to examine the neurophysiological underpinnings of behavior in rats, we developed a behavioral system for studying sensory processing, attention and discrimination learning in rats while recording firing patterns of neurons in one or more brain areas of interest. Because neuronal activity is sensitive to variations in behavior which may confound the identification of neural correlates, a specific aim of the study was to allow rats to sample sensory stimuli under conditions of strong behavioral regularity. Our behavioral system allows multimodal stimulus presentation and is coupled to modules for delivering reinforcement, simultaneous monitoring of behavior and recording of ensembles of well isolated single neurons. Using training protocols for simple and compound discrimination, we validated the behavioral system with a group of 4 rats. Within these tasks, a majority of medial prefrontal neurons showed significant firing‐rate changes correlated to one or more trial events that could not be explained from significant variation in head position. Thus, ensemble recordings can be combined with discriminative learning tasks under conditions of strong behavioral regularity.     

Lexical and sublexical units in speech perception

Saffran, Newport, and Aslin (1996a) found that human infants are sensitive to statistical regularities corresponding to lexical units when hearing an artificial spoken language. Two sorts of segmentation strategies have been proposed to account for this early word-segmentation ability: bracketing strategies, in which infants are assumed to insert boundaries into continuous speech, and clustering strategies, in which infants are assumed to group certain speech sequences together into units ( Swingley, 2005 ). In the present study, we test the predictions of two computational models instantiating each of these strategies i.e., Serial Recurrent Networks: Elman, 1990 ; and Parser: Perruchet & Vinter, 1998 in an experiment where we compare the lexical and sublexical recognition performance of adults after hearing 2 or 10 min of an artificial spoken language. The results are consistent with Parser's predictions and the clustering approach, showing that performance on words is better than performance on part-words only after 10 min. This result suggests that word segmentation abilities are not merely due to stronger associations between sublexical units but to the emergence of stronger lexical representations during the development of speech perception processes.     

Teachers' Ratings of Attention-Deficit Hyperactivity Disorder and Decisions for Referral for Services in Taiwan

We examined the relationship between elementary teachers' perceptions and ratings of Attention-Deficit Hyperactivity Disorder (ADHD) symptoms of students and their referral decisions in public schools in Taiwan. One hundred and twenty-one homeroom teachers were randomly selected from six public elementary schools in Taipei County, Taiwan, to participate in the study. The study contained two groups of children, a random sample (n — 478) and a nominated sample (n = 219). Results of the discriminant analyses showed that Chinese teachers' ratings of ADHD could predict group membership as to whether a student had been or might be referred. This study found that, despite the fact that Chinese teachers believed children with scores two standard deviations above the mean had behavior problems, teachers decided not to refer those students. Teachers were more likely to refer children whose scores were three standard deviations above the mean.     

The effects of differing response types and price manipulations on demand measures

Animals' behavioral needs have become an important component of animal welfare legislation. Behavioral economics provides a framework for the study of such needs. A function, analogous to a demand function relating consumption rate to price, can be obtained by increasing the price (or work) required for access to a commodity. This experiment investigated the effects of different response types and price manipulations on these functions. Six hens pushed a door or pecked a key for food under open economic conditions (short experimental sessions and supplementary food). In Part 1, the number of door pushes required (fixed-ratio schedule) was increased each session, and the force needed to push the door was increased across conditions. In Part 2, the force needed to push the door was increased session to session, and the fixed-ratio schedule was increased across conditions. In Part 3, the number of key pecks required was increased each session. Both response types produced similarly shaped (approximately linear in logarithmic coordinates and downward sloping) demand functions when price was increased by increasing the number of responses required. These imply an elastic demand for food under these conditions. In contrast, increasing the force required to push the door resulted in highly curvilinear functions. These functions indicated little change in consumption across lower door forces and abrupt drops in consumption at higher force requirements, implying mixed elasticity in the animals' demand for food. The differences between the shapes of the two functions seem to arise from the different ways that the two price manipulations alter the time taken to complete the work required. Increasing the fixed-ratio requirement necessarily increases the time needed to complete each response unit, whereas increasing the force requirement does not. The different shapes of the functions were robust when either force or number was varied across sessions and the value of the other was varied over conditions. They were also robust when the price increases were taken from different conditions, showing that the shapes of the functions were independent of the place in the experiment in which the price was examined. Unit price (which combines number and force into a single price measure) unified the data from the two price manipulations to a large degree, producing moderately curved functions. However, there was some variance around the unit price functions, and this was attributable to the different shapes of the underlying functions. The data suggest that different price manipulations may give different measures of animal demand but that unit price might provide some unification.     

Phrasal Unit Boundaries and Organization of Turns and Sequences in Korean Conversation

This paper examines an aspect of the grammar-interaction interface with respect to how participants orient to intra-turn phrasal unit boundaries as a locus that has interactional import for turn and sequence organization in Korean conversation. Phrasal unit boundaries in Korean serve as a space within a turn in which the speaker of the turn in-progress invites the recipient to acknowledge the speaker's point expressed up-to-that-point and collaboratively display his/her understanding thereof. In a sequentially and topically 'ripe' context, such unit boundaries often constitute places where more active participation on the part of the recipient is invited in the form of collaborative completion in which the recipient co-constructs the primary speaker's on-going turn. Phrasal unit boundaries also provide interactional resources which the speaker may exploit to sequentially delete out a problem in talk, e.g., by a sort of tying operation in which a subsequently added phrasal unit ties back to the speaker's previous utterance to the effect that the intervening talk containing a problem is canceled out by way of being shown to have been an interruption of the speaker's turn in-progress. This practice points to an aspect of the way in which the 'agglutinative' grammatical process involving the use of phrasal units shapes interactional patterns as observed in the course of organizing turns/sequences and managing problems in talk.     

Segmentation of object outlines into parts: a large-scale integrative study

In this study, a large number of observers (N=201) were asked to segment a collection of outlines derived from line drawings of everyday objects (N=88). This data set was then used as a benchmark to evaluate current models of object segmentation. All of the previously proposed rules of segmentation were found supported in our results. For example, minima of curvature (i.e. locations along the contour where negative curvature takes an extreme value) were often used as segmentation points. The second point of a pair connected by a segmentation line often depended on more global shape characteristics such as proximity, collinearity, symmetry, and elongation. Based on these results, a framework is presented in which all of the previously proposed (and now empirically validated) segmentation rules or rules for part formation are integrated.     

汉语老年读者的多词单元加工：来自眼动研究的证据

选取由两个双字词组成的多词组合（单词组合、模糊词组合、双词组合）,比较老年人和青年人对多词单元的加工情况。结果发现,相比于其他两类组合,所有被试在单词组合上的注视时间更短,第一遍注视次数更少,成分词上的注视时间更短,跳读率更高,表现出多词单元的加工优势,而且这一加工优势不存在显著的年龄差异。结果表明,汉语老年读者同样将多词单元作为整体进行加工。     

Positive Gaze Preferences in Older Adults: Assessing the Role of Cognitive Effort with Pupil Dilation

ABSTRACT

Older adults display positive preferences in their gaze, consistent with their prioritization of emotion regulation goals. While some research has argued that substantial amounts of cognitive effort are necessary for these information-processing preferences to occur, other work suggests that these attentional patterns unfold with minimal cognitive exertion. The current study used an implicit regulatory context (i.e., viewing facial stimuli of varying emotions) to assess how much cognitive effort was required for positive attentional preferences to occur. Effortful cognitive processing was assessed with a direct measure of change in pupil dilation. Results indicated that minimal cognitive effort was expended when older adults engaged in positive gaze preferences. This finding suggests that gaze acts as a rather effortless and economical regulatory tool for individuals to shape their affective experience.