Attention and prediction modulations in expected and unexpected visuospatial trajectories

Humans are constantly exposed to a rich tapestry of visual information in a potentially changing environment. To cope with the computational burden this engenders, our perceptual system must use prior context to simultaneously prioritise stimuli of importance and suppress irrelevant surroundings. This study investigated the influence of prediction and attention in visual perception by investigating event-related potentials (ERPs) often associated with these processes, N170 and N2pc for prediction and attention, respectively. A contextual trajectory paradigm was used which violated visual predictions and neglected to predetermine areas of spatial interest, to account for the potentially unpredictable nature of a real-life visual scene. Participants (N = 36) viewed a visual display of cued and non-cued shapes rotating in a five-step predictable trajectory, with the fifth and final position of either the cued or non-cued shape occurring in a predictable or unpredictable spatial location. To investigate the predictive coding theory of attention we used factors of attention and prediction, whereby attention was manipulated as either cued or non-cued conditions, and prediction manipulated in either predictable or unpredictable conditions. Results showed both enhanced N170 and N2pc amplitudes to unpredictable compared to predictable stimuli. Stimulus cueing status also increased N170 amplitude, but this did not interact with stimulus predictability. The N2pc amplitude was not affected by stimulus cueing status. In accordance with previous research these results suggest the N170 is in part a visual prediction error response with respect to higher-level visual processes, and furthermore the N2pc may index attention reorientation. The results demonstrate prior context influences the sensitivity of the N170 and N2pc electrophysiological responses. These findings add further support to the role of N170 as a prediction error signal and suggest that the N2pc may reflect attentional reorientation in response to unpredicted stimulus locations.

Lexical Strata and Phonotactic Perplexity Minimization

We present a model of gradient phonotactics that is shown to reduce overall phoneme uncertainty in a language when the phonotactic grammar is modularized in an unsupervised fashion to create more than one sub-grammar. Our model is a recurrent neural network language model (Elman 1990), which, when applied in two separate, randomly initialized modules to a corpus of Japanese words, learns lexical subdivisions that closely correlate with two of the main lexical strata for Japanese (Yamato and Sino-Japanese) proposed by Ito and Mester (1995). We find that the gradient phonotactics learned by the model, which are based on the entire prior context of a phoneme, reveal a continuum of gradient strata membership, similar to the gradient membership proposed by Hayes (2016) for the Native vs. Latinate stratification in English.

Prior context influences motor brain areas in an auditory oddball task and prefrontal cortex multitasking modelling

In this study, the relationship of orienting of attention, motor control and the Stimulus- (SDN) and Goal-Driven Networks (GDN) was explored through an innovative method for fMRI analysis considering all voxels in four experimental conditions: standard target (Goal; G), novel (N), neutral (Z) and noisy target (NG). First, average reaction times (RTs) for each condition were calculated. In the second-level analysis, ‘distracted’ participants, as indicated by slower RTs, evoked brain activations and differences in both hemispheres’ neural networks for selective attention, while the participants, as a whole, demonstrated mainly left cortical and subcortical activations. A context analysis was run in the behaviourally distracted participant group contrasting the trials immediately prior to the G trials, namely one of the Z, N or NG conditions, i.e. Z.G, N.G, NG.G. Results showed different prefrontal activations dependent on prior context in the auditory modality, recruiting between 1 to 10 prefrontal areas. The higher the motor response and influence of the previous novel stimulus, the more prefrontal areas were engaged, which extends the findings of hierarchical studies of prefrontal control of attention and better explains how auditory processing interferes with movement. Also, the current study addressed how subcortical loops and models of previous motor response affected the signal processing of the novel stimulus, when this was presented laterally or simultaneously with the target. This multitasking model could enhance our understanding on how an auditory stimulus is affecting motor responses in a way that is self-induced, by taking into account prior context, as demonstrated in the standard condition and as supported by Pulvinar activations complementing visual findings. Moreover, current BCI works address some multimodal stimulus-driven systems.

Prior context influences motor brain areas in an auditory oddball task and prefrontal cortex multitasking modelling

In this study, the relationship of orienting of attention, motor control and the Stimulus- (SDN) and Goal-Driven Networks (GDN) was explored through an innovative method for fMRI analysis considering all voxels in four experimental conditions: standard target (Goal; G), novel (N), neutral (Z) and noisy target (NG). First, average reaction times (RTs) for each condition were calculated. In the second level analysis, ‘distracted’ participants, as indicated by slower RTs, evoked brain activations and differences in both hemispheres’ neural networks for selective attention, while the participants, as a whole, demonstrated mainly left cortical and subcortical activations. A context analysis was run in the behaviourally distracted participant group contrasting the trials immediately prior to the G trials, namely one of the Z, N or NG conditions, i.e. Z.G, N.G, NG.G. Results showed different prefrontal activations dependent on prior context in the auditory modality, recruiting between 1 to 10 prefrontal areas. The higher the motor response and influence of the previous novel stimulus, the more prefrontal areas were engaged, which extends the findings of hierarchical studies of prefrontal control of attention and better explains how auditory processing interferes with movement. Also, the current study addressed how subcortical loops and models of previous motor response affected the signal processing of the novel stimulus, when this was presented laterally or simultaneously with the target. This multitasking model could enhance our understanding on how an auditory stimulus is affecting motor responses in a way that is self-induced, by taking into account prior context, as demonstrated in the standard condition and as supported by Pulvinar activations complementing visual findings. Moreover, current BCI works address some multimodal stimulus-driven systems.

‘Die’ and its different situation-bound utterances in Persian

In this paper, using the tenets of Situation-Bound Utterances (SBUs) (Kecskes 2000, 2010) and referring to Pragmatic Act Theory (PAT) (Mey 2001), the verb mordan (‘to die’ in English), and its different realisations are analysed among Persian speakers. Through the analysis of authentic talk in interaction, this study aims to ponder nonstandard (situation-derived) meanings of the term mordan and its different SBUs. The primary focus of the study is on strings of linguistic events as well as the “conventions of usage” (Morgan 1978) or cultural understanding that may lead to standard and nonstandard meanings considering mordan and its different SBUs. The findings suggest that the SBUs regarding mordan, a neglected sociolinguistic context, not only is affected by its actual situational characteristics but also by prior context encoded in utterances used, which manifests culture-specific ways of thinking (Capone 2018; Wong 2010). Overall, 19 SBUs and 7 generic categories were identified with regard to the verb mordan in Persian. This paper exhibits that mordan is a versatile verb, which, when combined with situational/contextual factors, conveys different nonstandard functions that fulfil social needs. This study will also refer to linguistic features underlying SBUs that are influential in assigning various distinct meanings to the verb mordan in Persian.

Attention and prediction modulations in expected and unexpected visuospatial trajectories

Humans are constantly exposed to a rich tapestry of visual information in a potentially changing environment. To cope with the computational burden this engenders, our perceptual system must use prior context to simultaneously prioritise stimuli of importance and suppress irrelevant surroundings. This study investigated the influence of prediction and attention in visual perception by investigating event-related potentials (ERPs) often associated with these processes, N170 and N2pc for prediction and attention respectively. A contextual trajectory paradigm was used which violated visual predictions and neglected to predetermine areas of spatial interest, to account for the potentially unpredictable nature of a real-life visual scene. Participants (N=36) viewed a visual display of cued and non-cued shapes rotating in a five-step predictable trajectory, with the fifth and final position of either the cued or non-cued shape occurring in a predictable or unpredictable spatial location. Results showed both enhanced N170 and N2pc amplitudes to unpredictable compared to predictable stimuli, and furthermore the N170 was larger to cued than non-cued stimuli. In accordance with previous research these results suggest the N170 is in part a visual prediction error response with respect to higher-level visual processes, and furthermore the N2pc may index attention reorientation. The results demonstrate prior context influences the sensitivity of the N170 and N2pc electrophysiological responses. The findings suggest attention boosts the precision of prediction error signals, furthering our understanding of how expectation can modulate prediction in selective visuospatial attention. Implications of this research provide insight into how prior context in visuospatial motion guides attention in a visual scene.

Idioms in Context: Evidence from a Time Cloze-Response Study

Summary This article reports on two timed cloze-response experiments which examine the impact of context on idiom recognition. Study 1 presented participants with the beginnings of Polish VP idioms without any prior context. Cloze probabilities and response times for idiom continuations were measured to establish the idiom recognition point (IRP) for each idiom. In Study 2, we used the same idioms in two kinds of contexts: (i) supporting a figurative meaning and (ii) supporting a literal meaning. Cloze probability and response times were measured at the IRP and one word before and after it. The figurative meaning of idioms was automatically activated at the IRP independently of the type of context. Additionally, the figurative context did not move the IRP to an earlier position, whereas in the literal context the responses were significantly slower at the IRP as compared to the figurative context condition. Such a finding indicates that, irrespective of the literal context, the comprehenders automatically activated the figurative meaning of an idiom at the IRP, but they had to discard it later. The literal meaning was computed from the literal meanings of idiom constituents stored in idiom lexical representation, which was computationally costly.

Prior context influences motor brain areas in an auditory oddball task and prefrontal cortex multitasking modelling

In this study, the relationship of orienting of attention, motor control and the Stimulus- (SDN) and Goal-Driven Network (GDN) was explored through an innovative method for fMRI analysis considering all voxels after every type condition. The task consisted of four conditions: standard target (G), novel (N), neutral (Z) and noisy target (NG). First running average reaction times of each condition was made. In the second level analysis, ‘distracted’ participants evoke brain activations and differences in both hemispheres neural network for selective attention as previously reported while the participants, as a whole, demonstrated mainly left cortical and subcortical activations. A context analysis was run in the behaviourally distracted participant group contrasting the trials immediately prior to the G trials, namely one of the Z, N or NG conditions. Results showed different prefrontal activations were evoked dependent on prior context in auditory modality with recruiting from 1 to 10 brain prefrontal areas. The more motor response and influence of the previous novel stimulus the more prefrontal areas, which extend hierarchical studies of prefrontal control of attention and explain better how the auditory processing interferes with movement. Also, it was addressed how subcortical loops and model of previous motor response affected the signal processing the novel stimulus, lateralized or simultaneously, with the Target. This model makes the first grasp to understand how auditory stimulus is changing motor responses in a kind of self-induced motor response. Moreover, current BCI works address some multimodal stimulus-driven systems.

Decoding the Real-Time Neurobiological Properties of Incremental Semantic Interpretation

Communication through spoken language is a central human capacity, involving a wide range of complex computations that incrementally interpret each word into meaningful sentences. However, surprisingly little is known about the spatiotemporal properties of the complex neurobiological systems that support these dynamic predictive and integrative computations. Here, we focus on prediction, a core incremental processing operation guiding the interpretation of each upcoming word with respect to its preceding context. To investigate the neurobiological basis of how semantic constraints change and evolve as each word in a sentence accumulates over time, in a spoken sentence comprehension study, we analyzed the multivariate patterns of neural activity recorded by source-localized electro/magnetoencephalography (EMEG), using computational models capturing semantic constraints derived from the prior context on each upcoming word. Our results provide insights into predictive operations subserved by different regions within a bi-hemispheric system, which over time generate, refine, and evaluate constraints on each word as it is heard.