How do the hierarchical levels of premises affect category-based induction: diverging effects from the P300 and N400

Exploration of Categorization and Category-Based Induction on Waste Sorting: A Follow-Up Observation by NeuroSky MindWave

Waste sorting, as an embodiment of behavioral cognition, is regulated by two cognitive processes, namely, Categorization (C) and Category-Based Induction (CBI). This study employed the event-related potential (ERP) technique to assess whether there is a transformation between C and CBI in waste sorting cognition, in order to help individuals establish a correct waste sorting behavior. We reported a case of intervention in waste sorting education with a 58-year-old Chinese woman to discriminate whether such intervention facilitates the transition between C and CBI. The results showed that the waste sorting cognition follows a developmental model as C-CBI-C, where education may help the subject build a cognitive framework for waste sorting by altering inherent misperceptions and filling gaps in classification knowledge. The results also noticed that FN400 is identified as a characteristic waveform in the CBI process, by which it is indicated that the first 4 to 7 days of education is a critical period for establishing the cognitive framework. Through a comparison of the ERP waveforms at different stages of intervention, the results are insightful to help individuals improve their cognition of waste sorting.

Brain electrical traits of logical validity

Neuroscience has studied deductive reasoning over the last 20 years under the assumption that deductive inferences are not only de jure but also de facto distinct from other forms of inference. The objective of this research is to verify if logically valid deductions leave any cerebral electrical trait that is distinct from the trait left by non-valid deductions. 23 subjects with an average age of 20.35 years were registered with MEG and placed into a two conditions paradigm (100 trials for each condition) which each presented the exact same relational complexity (same variables and content) but had distinct logical complexity. Both conditions show the same electromagnetic components (P3, N4) in the early temporal window (250-525 ms) and P6 in the late temporal window (500-775 ms). The significant activity in both valid and invalid conditions is found in sensors from medial prefrontal regions, probably corresponding to the ACC or to the medial prefrontal cortex. The amplitude and intensity of valid deductions is significantly lower in both temporal windows (p = 0.0003). The reaction time was 54.37% slower in the valid condition. Validity leaves a minimal but measurable hypoactive electrical trait in brain processing. The minor electrical demand is attributable to the recursive and automatable character of valid deductions, suggesting a physical indicator of computational deductive properties. It is hypothesized that all valid deductions are recursive and hypoactive.

Common and distinctive cognitive processes between categorization and category-based induction: Evidence from event-related potentials

Categorization involves forming equivalence classes of discriminable entities, whereas category-based induction (CBI) involves employing categorical knowledge to generalize novel properties. Previous studies have suggested either common or distinctive cognitive processing between categorization and CBI. However, no study has compared cognitive processes with the same stimuli sets using event-related potentials (ERPs), which help to determine the cognitive processes with a high temporal solution. In this study, we compared the ERP responses to categorization and CBI using two separate experiments (i.e., generic and specific conclusions), with the same task materials. Results from both experiments identified distinctive cognitive processing between categorization and CBI based on a greater proportion of "definitely" responses and smaller amplitudes of sustained negativity during categorization. These observations suggest that categorization involves decreased conflict monitoring and control than CBI under single-premise conditions. Contrastingly, categorization and CBI elicited similar FN400 amplitudes in both experiments, which suggests a common cognitive process between them. These findings present the common and distinctive cognitive processes between categorization and CBI.

How types of prior knowledge and task properties impact the category-based induction: diverging evidence from the P2, N400, and LPC effects

Category-based induction task was combined with ERP to unravel whether prior knowledge and property interact when inferring on genes or diseases. Larger P2 amplitudes for near taxonomic/causal distances relative to far ones, as well as larger LPC for taxonomic relation relative to thematic relation, are found in both gene and disease tasks. However, smaller N400 is found for taxonomic relation in gene task and thematic relation in disease task, respectively, and larger LPC at 700-850 ms for near taxonomic distance in the gene task and near causal distance in the disease task. These results suggested that the category-based inductive reasoning is context-sensitive, and there may be four stages of category-based inductive reasoning: the early automatic comparison of features/relations (P2), features/relations generalization process (N400), the extraction of common relationship/rule (LPC at 550-700 ms), the inference generation (LPC at 700-850 ms).

P3a amplitude is related to conclusion specificity during category-based induction

Category-based induction involves the generalization of a novel property (conclusion property) to a new category (conclusion category), based on the knowledge that a category exemplar (premise category) has the respective novel property. Previous studies have shown that conclusion specificity (i.e., specific [S] or generic categories [G]) influences category-based induction. However, the timing of brain activity underlying this effect is not well known, especially with controlling the similarities of premise and conclusion categories between S and G arguments. In this study, the event-related potential (ERP) responses to category-based induction between S and G arguments were compared under both congruent (+, premise and conclusion categories are related) and incongruent (-, premise and conclusion categories are unrelated) arguments; additionally, the similarities of premise and conclusion categories between S and G arguments were controlled. The results showed that replicating this effect, S+ arguments have increased “strong” response rates compared to G+ arguments, suggesting that category-based induction is contingent on factors beyond matched similarities. Moreover, S arguments have more liberal inductive decision thresholds than G arguments, which suggest that conclusion specificity affects the inductive decision reflected by inductive decision thresholds. Furthermore, G+ arguments elicit greater P3a amplitudes than S+ arguments, which suggest greater attention resources allocation to the review of decisions for G+ arguments than that for S+ arguments. Taken together, the conclusion specificity effect during semantic category-based induction can be revealed by “strong” response rates, inductive decision thresholds, and P3a component after controlling the premise-conclusion similarity, providing evidence that category-based induction rely on more than simple similarity judgment and conclusion specificity would affect category-based induction.

The Influence of Hierarchical Masks on Masked Repetition Priming: Evidence From Event-Related Potential Investigation

The discussion about relationship between prime and target has contributed to the mechanism of priming effect and object recognition. Nevertheless, the role of relationship between mask and target in those cognitive processes remains unquestioned. In the present study, we aim to investigate how mask-target hierarchical relationship may affect word priming and familiarity, by using the masked repetition paradigm and manipulating three hierarchical relationship between mask and target. It is hypothesized that a closer hierarchical relationship between mask and target is associated with a higher mask target similarity, and thereby it leads to a worse recognition performance. Our behavioral results do not support this hypothesis by showing no effect of mask target hierarchical relationship on response time (RT) and accuracy. Event-related potentials (ERPs) indicated that highly similar mask-target triggered (i.e., the subordinate-subordinate-subordinate trials) larger N1 amplitudes, suggesting that it requires more cognitive resource to discriminate the stimuli. In addition, trials with highly similar mask-target hierarchical relationship induced smaller P2 (150–250 ms) and larger mid-frontal FN400 amplitudes than do trials with low mask-target similarity (i.e., the subordinate-basic-subordinate and the subordinate-superordinate-subordinate trials). Our results suggested that the similarity between mask and target may impede conceptual fluency to reduce word priming and familiarity effect.

P300 and positive slow waves reveal the plausibility in inductive reasoning

Category-based induction is an advanced cognitive function that is based on our category-level knowledge. Previous findings have recognized the distance effect in category-based induction: Inductive strength is affected by the hierarchical distance between the premises and conclusions. However, the neural mechanisms underlying this effect require elucidation. In the present study, we investigated the neural mechanisms of the distance effect by using EEG technology and a new experimental paradigm-category-based induction. In this paradigm, we used three hierarchical levels of categories-the subordinate category, the basic category, the superordinate category-and an irrelevant category. We further used these categories to create four types of trial that varied in the hierarchical distance between the premise and the conclusion: the subordinate-basic, the basic-superordinate, the subordinate-superordinate, and the irrelevant-superordinate trials. In each trial, participants judged the probability that the conclusion category had the same property as the premise category. Our behavioral results revealed that people responded more slowly in the irrelevant-superordinate trials than in the basic-superordinate and the subordinate-basic trials. Our ERP results showed that the irrelevant-superordinate trials elicited smaller P300 (250-500 ms) amplitudes than did the subordinate-basic and the basic-superordinate trials. In addition, the subordinate-superordinate trials elicited smaller P300 and PSW (700-998 ms) amplitudes than did the subordinate-basic and the basic-superordinate combinations. These findings indicate that the amplitudes of P300 and PSW may reflect the distance effect in inductive reasoning: The further the premise-conclusion hierarchical distance, the lower the inductive strength, and thus the smaller the P300 and PSW amplitudes.

FN400 and sustained negativity reveal a premise monotonicity effect during semantic category-based induction

The premise monotonicity effect during category-based induction is a robust effect that occurs when generalization of a novel property shared by many cases is more likely than one shared by few cases. The timing of brain activity during this effect is unclear. Therefore, the event-related potentials (ERPs) underpinning this effect were measured by manipulating the premise sample size (single [S] vs. two [T]) in a semantic category-based induction task, with the conclusion categories either including the premise categories (congruent induction) or not (incongruent induction). The behavioral results replicated the premise monotonicity effect, and revealed that S arguments produced longer reaction times and more conservative response criteria than did T arguments. This suggests that the premise monotonicity effect was affected by both evidence accumulation speed and decision threshold. ERP results demonstrated that the premise monotonicity effect was reflected by two parameters during inductive decision: (1) S arguments elicited larger FN400 amplitudes than did T arguments under congruent induction, which was linked to reduced global similarity, decreased cognitive relevance, and attenuated conceptual fluency and (2) S arguments elicited larger sustained negativity (SN) in the 450-1050-ms time window than did T arguments, which is related to more inference-driven integration and interpretive processes. Our findings provide insight into the complex temporal course of the premise monotonicity effect during semantic category-based induction.

FN400 amplitudes reveal the differentiation of semantic inferences within natural vs. artificial domains

Category-based inferences allow inductions about novel properties based on categorical memberships (e.g., knowing all trout have genes [premise] allows us to infer that all fish have genes [conclusion]). Natural (N) and artificial (A) domains are the most obvious and traditional distinctions in categorization. The distinct event-related potential (ERP) responses for N and A domains have not yet been examined during category-based inferences. In this study, the differences between ERP inference parameters within N and A domains were measured during inductive decision processing, while controlling the premise−conclusion similarity and premise typicality between those two domains. Twenty-two adults were asked to make a decision on whether a conclusion was definitely weak, possibly weak, possibly strong, or definitely strong, based on a premise. The behavioral results showed that semantic inferences within the N domain shared similar inductive strength, similar “correct” response rates, and similar reaction times with that within the A domain. However, the ERP results showed that semantic inferences elicited smaller frontal-distributed N400 (FN400) amplitudes within the N domain than within the A domain, which suggested that knowledge of the ontological domain of a category affects category-based inferences, and underlaid the increased categorical coherence and homogeneity in the N as compared to the A categories. Therefore, we have distinguished the cognitive course of semantic inferences between N and A domains.