The role of working memory in inferential sentence comprehension

Existing literature on inference making is large and varied. Trabasso and Magliano (Discourse Process 21(3):255–287, 1996) proposed the existence of three types of inferences: explicative, associative and predictive. In addition, the authors suggested that these inferences were related to working memory (WM). In the present experiment, we investigated whether WM capacity plays a role in our ability to answer comprehension sentences that require text information based on these types of inferences. Participants with high and low WM span read two narratives with four paragraphs each. After each paragraph was read, they were presented with four true/false comprehension sentences. One required verbatim information and the other three implied explicative, associative and predictive inferential information. Results demonstrated that only the explicative and predictive comprehension sentences required WM: participants with high verbal WM were more accurate in giving explanations and also faster at making predictions relative to participants with low verbal WM span; in contrast, no WM differences were found in the associative comprehension sentences. These results are interpreted in terms of the causal nature underlying these types of inferences.     

Preparation of forefinger’s sequence on keyboard orients ocular fixations on computer screen

This study examined the links between attention, hand movements and eye movements when performed in different spatial areas. Participants performed a visual search task on a computer screen while preparing to press two keyboard keys sequentially with their index. Results showed that the planning of the manual sequence influenced the latency of the first saccade and the placement of the first fixation. In particular, even if the first fixation placement was influenced by the combination of both components of the prepared manual sequence in some trials, it was affected principally by the first component of the prepared manual sequence. Moreover, the probability that the first fixation placement did reflect a combination of both components of the manual sequence was correlated with the speed of the second component. This finding suggests that the preparation of the second component of the sequence influence simultaneous oculomotor behavior when motor control of the manual sequence relied on proactive motor planning. These results are discussed taking into account the current debate on the eye/hand coordination research.     

Visual field dependence as a navigational strategy

Visual perception is an important component of environmental navigation. Previous research has revealed large individual differences in navigational strategies (i.e., the body’s kinesthetic and embodied approach to movement) and the perception of environmental surfaces (via distance estimations), but little research has investigated the potential relationship between these sources of individual variation. An important navigational strategy is the interaction between reliance on visual cues and vestibular or proprioceptive cues. We investigated the role of this navigational strategy in the perception of environmental surfaces. The results supported three embodied evolutionary predictions: Individuals who were most reliant on visual context (1) overestimated vertical surfaces significantly more, and (2) feared falling significantly more, than did those who were least reliant on visual context; and (3) all individuals had roughly accurate horizontal distance estimates, regardless of their navigational strategy. These are among the first data to suggest that individual differences in perception are closely related to the individual differences in navigation that derive from navigational risks. Variable navigational strategies may reflect variable capacities to perceive and navigate the environment.     

The bisection point across variants of the task

Bisection tasks are used in research on normal space and time perception and to assess the perceptual distortions accompanying neurological disorders. Several variants of the bisection task are used, which often yield inconsistent results, prompting the question of which variant is most dependable and which results are to be trusted. We addressed this question using theoretical and experimental approaches. Theoretical performance in bisection tasks is derived from a general model of psychophysical performance that includes sensory components and decisional processes. The model predicts how performance should differ across variants of the task, even when the sensory component is fixed. To test these predictions, data were collected in a within-subjects study with several variants of a spatial bisection task, including a two-response variant in which observers indicated whether a line was transected to the right or left of the midpoint, a three-response variant (which included the additional option to respond “midpoint”), and a paired-comparison variant of the three-response format. The data supported the model predictions, revealing that estimated bisection points were least dependable with the two-response variant, because this format confounds perceptual and decisional influences. Only the three-response paired-comparison format can separate out these influences. Implications for research in basic and clinical fields are discussed.     

Quantity discrimination by kittens of the domestic cat (Felis silvestris catus)

Animal Cognition - Quantitative abilities are well described in many species and in diverse life situations, including in the adult domestic cat. However, such abilities have been much less studied...     

Tolerant macaque species are less impulsive and reactive

Animal Cognition - Inhibitory control, the inhibition of impulsive behaviours, is believed to be key in navigating a complex social environment. Species characterised by higher social tolerance,...     

Rhetorical Strategies for Scientific Authority: A Boundary-Work Analysis of ‘Climategate’

The term ‘Climategate’ refers to the episode in November 2009 when emails between climate scientists were stolen and published online. The content of this private correspondence prompted criticism from diverse commentators who cast doubts on the methods, claims, and members of the climate science community. In response, individual scientists and scientific institutions published statements responding to the allegations of scientific fraud. Gieryn's concept of ‘boundary-work’ can be used to analyse the rhetoric of scientists in situations where their legitimacy is disputed. More specifically, boundary-work can be used to analyse the responses of scientists in terms of: how they represent the attributes of science, what types of boundary-work they undertake (e.g. expulsion, expansion, and protection), and the professional interests that come into play. A boundary-work analysis of the commentaries published in the aftermath of Climategate reveals that scientists characterised climate science as consensual, asocial, and open. Scientists depicted climate science as consensual with the purpose of expelling dissenters and protecting areas of climate science from criticism. Scientists also described knowledge about climate as being ideally produced apart from society so that they could preserve their autonomy and exclude individuals who are accused of being ‘politically biased’. Scientists characterised climate science as necessarily open as the means to justify both existing and additional public funding for science and to avoid external corrective interventions against scientific opacity. Scientists and their critics alike interpreted the stolen emails as embarrassing deviations from the alleged social demands of a consensual, objective, and accessible science.     

Targets of the memorized position and visual contexts]

The goal of this study was to determine whether a sensorimotor or cognitive encoding is used to encode a target position and save it into iconic memory. The methodology consisted of disrupting a manual aiming movement to a memorized visual target by displacing the visual field containing the target. The nature of the encoding was inferred from the nature and the size of the errors relative to a control. The target was presented either centrally or in the right periphery. Participants moved their hand from the left to the right of fixation. Black and white vertical stripes covered the whole visual field. The visual field was either stationary throughout the trial or was displaced to the right or left at the extinction of the target or at the start of the hand movement. In the latter case, the displacement of the visual field obviously could only be taken into account by the participant during the gesture. In this condition, our hypothesis was that the aiming error would follow the direction of visual field displacement. Results showed three major effects: (1) Vision of the hand during the gesture improved the final accuracy; (2) visual field displacement produced an underestimation of the target distance only when the hand was not visible during the gesture and was always in the same direction displacement; and (3) the effect of the stationary structured visual field on aiming precision when the hand was not visible depended on the distance to the target. These results suggest that a stationary structured visual field is used to support the memory of the target position. The structured visual field is more critical when the hand is not visible and when the target appears in peripheral rather than central vision. This suggests that aiming depends on memory of the relative peripheral position of the target (allocentric reference). However, in the present task, cognitive encoding does not maintain the "position" of the target in memory without reference to the environment. The systematic effect of the visual field displacement on the manual aiming suggests that the role of environmental reference frames in memory for position is not well understood. Some studies, in particular those of Giesbrecht and Dixon (1999) and Glover and Dixon (2001), suggested differing roles of the environment in the retention of the target position and the control of aiming movements toward the target. The present observations contribute to understanding the mechanism involved in locating and grasping objects with the hand.