Conceptual Hierarchies in a Flat Attractor Network: Dynamics of Learning and Computations

The structure of people's conceptual knowledge of concrete nouns has traditionally been viewed as hierarchical ( Collins & Quillian, 1969 ). For example, superordinate concepts ( vegetable ) are assumed to reside at a higher level than basic-level concepts ( carrot ). A feature-based attractor network with a single layer of semantic features developed representations of both basic-level and superordinate concepts. No hierarchical structure was built into the network. In Experiment and Simulation 1, the graded structure of categories (typicality ratings) is accounted for by the flat attractor network. Experiment and Simulation 2 show that, as with basic-level concepts, such a network predicts feature verification latencies for superordinate concepts ( vegetable ). In Experiment and Simulation 3, counterintuitive results regarding the temporal dynamics of similarity in semantic priming are explained by the model. By treating both types of concepts the same in terms of representation, learning, and computations, the model provides new insights into semantic memory.     

Sound improves diminished visual temporal sensitivity in schizophrenia

Visual temporal processing and multisensory integration (MSI) of sound and vision were examined in individuals with schizophrenia using a visual temporal order judgment (TOJ) task. Compared to a non-psychiatric control group, persons with schizophrenia were less sensitive judging the temporal order of two successively presented visual stimuli. However, their sensitivity to visual temporal order improved as in the control group when two accessory sounds were added (temporal ventriloquism). These findings indicate that individuals with schizophrenia have diminished sensitivity to visual temporal order, but no deficits in the integration of low-level auditory and visual information.     

Time perception and time perspective differences between adolescents and adults

The present experiment aimed to investigate the differences in time perception and time perspective between subjects representing two developmental stages, namely adolescence and middle adulthood. Twenty Chinese adolescents aged 15–25 and twenty Chinese adults aged 35–55 participated in the study. A time discrimination task and a time reproduction task were implemented to measure the accuracy of their time perception. The Zimbardo Time Perspective Inventory (Short-Form) was adopted to assess their time orientation. It was found that adolescents performed better than adults in both the time discrimination task and the time reproduction task. Adolescents were able to differentiate different time intervals with greater accuracy and reproduce the target duration more precisely. For the time reproduction task, it was also found that adults tended to overestimate the duration of the target stimuli while adolescents were more likely to underestimate it. As regards time perspective, adults were more future-oriented than adolescents, whereas adolescents were more present-oriented than adults. No significant relationship was found between time perspective and time perception.     

Grammatical aspect and event recognition in children’s online sentence comprehension

This study investigated whether or not the temporal information encoded in aspectual morphemes can be used immediately by young children to facilitate event recognition during online sentence comprehension. We focused on the contrast between two grammatical aspectual morphemes in Mandarin Chinese, the perfective morpheme –le and the (imperfective) durative morpheme –zhe. The perfective morpheme –le is often used to indicate that an event has been completed, whereas the durative morpheme –zhe indicates that an event is still in progress or continuing. We were interested to see whether young children are able to use the temporal reference encoded in the two aspectual morphemes (i.e., completed versus ongoing) as rapidly as adults to facilitate event recognition during online sentence comprehension. Using the visual world eye-tracking paradigm, we tested 34 Mandarin-speaking adults and 99 Mandarin-speaking children (35 three-year-olds, 32 four-year-olds and 32 five-year-olds). On each trial, participants were presented with spoken sentences containing either of the two aspectual morphemes while viewing a visual image containing two pictures, one representing a completed event and one representing an ongoing event. Participants’ eye movements were recorded from the onset of the spoken sentences. The results show that both the adults and the three age groups of children exhibited a facilitatory effect trigged by the aspectual morpheme: hearing the perfective morpheme –le triggered more eye movements to the completed event area, whereas hearing the durative morpheme –zhe triggered more eye movements to the ongoing event area. This effect occurred immediately after the onset of the aspectual morpheme, both for the adults and the three groups of children. This is evidence that young children are able to use the temporal information encoded in aspectual morphemes as rapidly as adults to facilitate event recognition. Children’s eye movement patterns reflect a rapid mapping of grammatical aspect onto the temporal structures of events depicted in the visual scene.     

Age-related changes in trunk neuromuscular activation patterns during a controlled functional transfer task include amplitude and temporal synergies

While healthy aging is associated with physiological changes that can impair control of trunk motion, few studies examine how spinal muscle responses change with increasing age. This study examined whether older (over 65 years) compared to younger (20–45 years) adults had higher overall amplitude and altered temporal recruitment patterns of trunk musculature when performing a functional transfer task. Surface electromyograms from twelve bilateral trunk muscle (24) sites were analyzed using principal component analysis, extracting amplitude and temporal features (PCs) from electromyographic waveforms. Two PCs explained 96% of the waveform variance. Three factor ANOVA models tested main effects (group, muscle and reach) and interactions for PC scores. Significant (p < .0125) group interactions were found for all PC scores. Post hoc analysis revealed that relative to younger adults, older adults recruited higher agonist and antagonistic activity, demonstrated continuous activation levels in specific muscle sites despite changing external moments, and had altered temporal synergies within abdominal and back musculature. In summary both older and younger adults recruit highly organized activation patterns in response to changing external moments. Differences in temporal trunk musculature recruitment patterns suggest that older adults experience different dynamic spinal stiffness and loading compared to younger adults during a functional lifting task.     

Memory for between‐list and within‐list information in amnesic patients with temporal lobe and diencephalic lesions

Patients with medial temporal lobe damage and diencephalic damage were compared on two tests of verbal temporal order memory: between‐list discrimination and within‐list discrimination. Both patient groups were impaired relative to a group of healthy control participants. In addition, despite comparable levels of item recognition, the diencephalic group was impaired relative to the medial temporal lobe group on both within‐list and between‐list discrimination. Temporal order memory for between‐list information showed a significant correlation with a composite measure of recognition memory, and the results are discussed in terms of the patients' reliance on familiarity and distance‐based processes to make temporal order judgments.     

Eavesdropping on character: Assessing everyday moral behaviors

Despite decades of interest in moral character, comparatively little is known about moral behavior in everyday life. This paper reports a novel method for assessing everyday moral behaviors using the Electronically Activated Recorder (EAR)—a digital audio-recorder that intermittently samples snippets of ambient sounds from people’s environments—and examines the stability of these moral behaviors. In three samples (combined N = 186), participants wore an EAR over one or two weekends. Audio files were coded for everyday moral behaviors (e.g., showing sympathy, gratitude) and morally-neutral comparison language behaviors (e.g., use of prepositions, articles). Results indicate that stable individual differences in moral behavior can be systematically observed in daily life, and that their stability is comparable to the stability of neutral language behaviors.     

The power and sensitivity of four core driver workload measures for benchmarking the distraction potential of new driver vehicle interfaces

This study evaluated the power and sensitivity of several core driver workload measures in order to better understand their use as a component of future driver distraction potential evaluation procedures of the in-vehicle human machine interface (HMI). Driving is a task that requires visual, manual and cognitive resources to perform. Secondary tasks, such as mobile phone use and interaction with in-built navigation, which load onto any of these three processing resources increase driver workload and can lead to impaired driving. Because workload and distraction potential are interrelated, a comprehensive method to assess driver workload that produces valid and predictive results is needed to advance the science of distraction potential evaluation. It is also needed to incorporate into New Car Assessment Program (NCAP) testing regimes. Workload measures of cognitive (DRT [Detection Response Task] Reaction Time), visual (DRT Miss Rate), subjective (NASA-TLX [driver workload questionnaire]), and temporal demand (Task Interaction Time) were collected as participants drove one of 40 vehicles while completing a variety of secondary tasks with varying interaction requirements. Of the evaluated measures, variance and power analyses demonstrated that Task Interaction Time is the most sensitive in detecting differences in driver workload between different in-vehicle HMIs, followed by DRT Miss Rate, NASA-TLX and finally DRT Reaction Time. There were relatively weak correlations between each of the four measures. These results suggest that Task Interaction Time, coupled with a reliable visual demand metric such as DRT Miss Rate, eye glance coding, or visual occlusion, more efficiently detect differences in driver workload between different HMIs compared to DRT Reaction Time and the NASA-TLX questionnaire. These results can be used to improve the understanding of the utility of each of these core driver workload measures in assessing driver distraction potential.