A saw is first identified as an object used on wood: ERP evidence for temporal differences between Thematic and Functional similarity relations

Spatial representations of objects used away and towards the body: The effect of near and far space

An action with an object can be accomplished only if we encode the position of the object with respect to our body (i.e., egocentrically) and/or to another element in the environment (i.e., allocentrically). However, some actions with the objects are directed towards our body, such as brushing our teeth, and others away from the body, such as writing. Objects can be near the body, that is within arm reaching, or far from the body, that is outside arm reaching. The aim of this study was to verify if the direction of use of the objects influences the way we represent their position in both near and far space. Objects typically used towards (TB) or away from the body (AB) were presented in near or far space and participants had to judge whether an object was closer to them (i.e., egocentric judgement) or closer to another object (i.e., allocentric judgement). Results showed that egocentric judgements on TB objects were more accurate in near than in far space. Moreover, allocentric judgements on AB objects were less accurate than egocentric judgements in near space but not in far space. These results are discussed with respect to the different roles that visuo-motor and visuo-spatial mechanisms play in near space and far space, respectively.

Brain Signatures of Embodied Semantics and Language: A Consensus Paper

According to embodied theories (including embodied, embedded, extended, enacted, situated, and grounded approaches to cognition), language representation is intrinsically linked to our interactions with the world around us, which is reflected in specific brain signatures during language processing and learning. Moving on from the original rivalry of embodied vs. amodal theories, this consensus paper addresses a series of carefully selected questions that aim at determining when and how rather than whether motor and perceptual processes are involved in language processes. We cover a wide range of research areas, from the neurophysiological signatures of embodied semantics, e.g., event-related potentials and fields as well as neural oscillations, to semantic processing and semantic priming effects on concrete and abstract words, to first and second language learning and, finally, the use of virtual reality for examining embodied semantics. Our common aim is to better understand the role of motor and perceptual processes in language representation as indexed by language comprehension and learning. We come to the consensus that, based on seminal research conducted in the field, future directions now call for enhancing the external validity of findings by acknowledging the multimodality, multidimensionality, flexibility and idiosyncrasy of embodied and situated language and semantic processes.

Multiple functions of the angular gyrus at high temporal resolution

Here, the functions of the angular gyrus (AG) are evaluated in the light of current evidence from transcranial magnetic/electric stimulation (TMS/TES) and EEG/MEG studies. 65 TMS/TES and 52 EEG/MEG studies were examined in this review. TMS/TES literature points to a causal role in semantic processing, word and number processing, attention and visual search, self-guided movement, memory, and self-processing. EEG/MEG studies reported AG effects at latencies varying between 32 and 800 ms in a wide range of domains, with a high probability to detect an effect at 300-350 ms post-stimulus onset. A three-phase unifying model revolving around the process of sensemaking is then suggested: (1) early AG involvement in defining the current context, within the first 200 ms, with a bias toward the right hemisphere; (2) attention re-orientation and retrieval of relevant information within 200-500 ms; and (3) cross-modal integration at late latencies with a bias toward the left hemisphere. This sensemaking process can favour accuracy (e.g. for word and number processing) or plausibility (e.g. for comprehension and social cognition). Such functions of the AG depend on the status of other connected regions. The much-debated semantic role is also discussed as follows: (1) there is a strong TMS/TES evidence for a causal semantic role, (2) current EEG/MEG evidence is however weak, but (3) the existing arguments against a semantic role for the AG are not strong. Some outstanding questions for future research are proposed. This review recognizes that cracking the role(s) of the AG in cognition is possible only when its exact contributions within the default mode network are teased apart.

Taxonomically-related Word Pairs Evoke both N400 and LPC at Long SOA in Turkish

Semantic priming in Turkish was examined in 36 right-handed healthy participants in a delayed lexical decision task via taxonomic relations using EEG. Prime-target relations included related- unrelated- and pseudo-words. Taxonomically related words at long stimulus onset asynchrony (SOA) were shown to modulate N400 and late positive component (LPC) amplitudes. N400 semantic priming effect in the time window of 300-500 ms was the largest for pseudo-words, intermediate for semantically-unrelated targets, and smallest for semantically-related targets as a reflection of lexical-semantic retrieval. This finding contributes to the ERP literature showing how remarkably universal the N400 brain potential is, with similar effects across languages and orthography. The ERP data also revealed different influences of related, unrelated, and pseudo-word conditions on the amplitude of the LPC. Attention scores and mean LPC amplitudes of related words in parietal region showed a moderate correlation, indicating LPC may be related to "relationship-detection process".

Taxonomic and thematic semantic relationships in picture naming as revealed by Laplacian-transformed event-related potentials

Semantically related concepts co-activate when we speak. Prior research reported both behavioral interference and facilitation due to co-activation during picture naming. Different word relationships may account for some of this discrepancy. Taxonomically related words (e.g., WOLF-DOG) have been associated with semantic interference; thematically related words (e.g., BONE-DOG) have been associated with facilitation. Although these different semantic relationships have been associated with opposite behavioral outcomes, electrophysiological studies have found inconsistent effects on event-related potentials. We conducted a picture-word interference electroencephalography experiment to examine word retrieval dynamics in these different semantic relationships. Importantly, we used traditional monopolar analysis as well as Laplacian transformation allowing us to examine spatially deblurred event-related components. Both analyses revealed greater negativity (150-250 ms) for unrelated than related taxonomic pairs, though more restricted in space for thematic pairs. Critically, Laplacian analyses revealed a larger negative-going component in the 300 to 500 ms time window in taxonomically related versus unrelated pairs which were restricted to a left frontal recording site. In parallel, an opposite effect was found in the same time window but localized to a left parietal site. Finding these opposite effects in the same time window was feasible thanks to the use of the Laplacian transformation and suggests that frontal control processes are concurrently engaged with cascading effects of the spread of activation through semantically related representations.

Event related potential exploration of the organizational structure of abstract versus concrete words in neurologically intact younger adults

The purpose of this study was to test the effects of concreteness and relationship type (similarity vs. association) on semantic processing using event-related potentials (ERP). Neurophysiological evidence has been found for the concreteness effect and for an effect of relationship type. This study replicated and extended these findings by investigating the interaction of concreteness and relationship type. Twenty-four neurologically healthy young adults performed lexical decision and semantic relatedness tasks while continuous scalp EEG was recorded. Larger N400 effects were found for concrete words in associative relationships than for concrete words in similarity relationships and abstract words in either type of relationship. The results are discussed in relation to the different representational frameworks account for abstract and concrete word processing.

How Processing Fluency Contributes to the Old/New Effects of Familiarity and Recollection: Evidence From the Remember/Know Paradigm

Previous investigations have demonstrated FN400 and LPC, 2 event-related potential old/new effects that respectively reflect familiarity- and recollection-based processes in memory. However, it is unclear whether these effects are susceptible to processing fluency, particularly different types of processing fluency. To address this issue, applying a masked priming paradigm, we conducted an event-related potential experiment by manipulating semantic relations between the prime and the target as identical (reflecting perceptual fluency), thematically and taxonomically related (referring to conceptual fluency), and unrelated. A remember/know (R/K) judgment task in the test phase was used to distinguish familiarity- and recollection-based processes. Behaviorally, both task performance and response speed were modulated by the variables of priming condition, item type, and response type. All 4 priming conditions elicited significant FN400 and LPC. Compared with the K response, the R response was more relevant to the recollection-based processes reflected by LPC. Both FN400 and LPC were modulated by whether there was a response of R, K, or new. The former was susceptible only to conceptual fluency, and the latter was sensitive to both perceptual fluency and conceptual fluency, which offered telling evidence for the dual process model. Considerations for future investigations are proposed. See supplemental materials here: https://www.press.uillinois.edu/journals/ajp/media/evidence_in_remember_know_paradigm/

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).

Neural dynamics of grip and goal integration during the processing of others' actions with objects: An ERP study

Recent behavioural evidence suggests that when processing others’ actions, motor acts and goal-related information both contribute to action recognition. Yet the neuronal mechanisms underlying the dynamic integration of the two action dimensions remain unclear. This study aims to elucidate the ERP components underlying the processing and integration of grip and goal-related information. The electrophysiological activity of 28 adults was recorded during the processing of object-directed action photographs (e.g., writing with pencil) containing either grip violations (e.g. upright pencil grasped with atypical-grip), goal violations (e.g., upside-down pencil grasped with typical-grip), both grip and goal violations (e.g., upside-down pencil grasped with atypical-grip), or no violations. Participants judged whether actions were overall typical or not according to object typical use. Brain activity was sensitive to the congruency between grip and goal information on the N400, reflecting the semantic integration between the two dimensions. On earlier components, brain activity was affected by grip and goal typicality independently. Critically, goal typicality but not grip typicality affected brain activity on the N300, supporting an earlier role of goal-related representations in action recognition. Findings provide new insights on the neural temporal dynamics of the integration of motor acts and goal-related information during the processing of others’ actions.

N400/frontal negativity reveals the controlled processes of taxonomic and thematic relationships in semantic priming for artifacts

Recent studies show that taxonomic and thematic relationships are functionally and neurologically dissociated; however, there remain some discrepancies due to inconsistencies in definitions, task properties, and concept domains. This issue was further explored via the semantic priming paradigm with a long SOA of 600 ms while controlling for perceptual or functional features of artifacts involved across taxonomic and thematic relationships. Six conditions were compared: perceptual relationship (axe-helve), functional relationship (axe-wood), perceptual classification (axe-hammer), functional classification (axe-saw), unrelated condition (axe-skates), and nonword (axe-derf) conditions. Behavioral priming effects are found for all related conditions relative to unrelated conditions except for perceptual relationships, whereas semantic priming effects (smaller N400 amplitude) are found for functional relationships and perceptual classification relative to unrelated conditions but not for perceptual relationships and functional classification, indicating perceptual features are less important than functional features for artifacts. Furthermore, the frontal negativity elicited by functional relationships is smaller than all other related conditions at 400-550 ms, while it is only smaller than functional classification at 550-650 ms. These results indicate that, besides different features, taxonomic and thematic relationships are dissociated to organize object knowledge, which is primarily fuelled by feature processing, with taxonomic, or thematic, relationships further embedded with such sensory, or functional, features.

Inductive Reasoning Differs Between Taxonomic and Thematic Contexts: Electrophysiological Evidence

Inductive reasoning can be performed in different contexts, but it is unclear whether the neural mechanism of reasoning performed in a thematic context (e.g., bee has x, so honey has x) is the same as that performed in a taxonomic context (e.g., bee has x, so butterfly has x). In the present study, participants were required to judge whether a conclusion was acceptable or not based on its premise, for which the taxonomic or thematic distances between premise and conclusion objects were either far or near. The Event related potential (ERP) results indicated that the effect of context (taxonomic vs. thematic) was initially observed in the P2 component; while the distance effect (far vs. near) was observed in N400 and late components. Moreover, the distance effect on thematic-based inductive reasoning was found in the anterior regions, while the distance effect on taxonomic-based inductive reasoning conditions was found in the posterior regions. These results support the view that inductive reasoning is performed differently under different semantic contexts.

Tool and object affordances: An ecological eye-tracking study

In the present eye-tracking study, we analysed the visuo-spatial attentional patterns of participants looking at 3D images depicting single tools and object-tool pairs. The object-tool pairs could be thematically consistent, thematically inconsistent or spatially inconsistent. During the first 500 ms of visual exploration, tools were fixated longer on their functional area in all experimental conditions. However, extending the time-window of analysis to 1750 ms, the visual scene was encoded in a faster and more suited-for-action way in the thematically consistent condition (e.g., hammer-nail). Most important, the visual exploration of the thematically consistent pairs focused on the manipulation area of the tool (e.g., the handle of the hammer) more than on its functional area (e.g., the head of the hammer). Finally, when single tools were shown and the entire time-window of analysis was considered (1750 ms), fixation focused on the tool's manipulation area. These results are discussed within the reasoning-based framework of tool use. They highlight the relative role of the visuo-perceptual context in affordance perception and suggest a novel interpretation of the cognitive mechanisms underlying the processing of tools and object-tool pairs in terms of action reappraisal (i.e., a re-functionalization process when the action possibility is mined by the visuo-perceptual context).

Co-activation of Taxonomic and Thematic Relations in Spoken Word Comprehension: Evidence From Eye Movements

Evidence from behavior, computational linguistics, and neuroscience studies supported that semantic knowledge is represented in (at least) two semantic systems (i.e., taxonomic and thematic systems). It remains unclear whether, and to what extent taxonomic and thematic relations are co-activated. The present study investigated the co-activation of the two types of semantic representations when both types of semantic relations are simultaneously presented. In a visual-world task, participants listened to a spoken target word and looked at a visual display consisted of a taxonomic competitor, a thematic competitor and two distractors. Growth curve analyses revealed that both taxonomic and thematic competitors attracted visual attention during the processing of the target word but taxonomic competitor received more looks than thematic competitor. Moreover, although fixations on taxonomic competitor rose faster than thematic competitor, these two types of competitors started to attract more fixations than distractor in a similar time window. These findings indicate that taxonomic and thematic relations are co-activated by the spoken word, the activation of taxonomic relation is stronger and rise faster than thematic relation.

Comparing the temporal dynamics of thematic and taxonomic processing using event-related potentials

We report the results of a study comparing the temporal dynamics of thematic and taxonomic knowledge activation in a picture-word priming paradigm using event-related potentials. Although we found no behavioral differences between thematic and taxonomic processing, ERP data revealed distinct patterns of N400 and P600 amplitude modulation for thematic and taxonomic priming. Thematically related target stimuli elicited less negativity than taxonomic targets between 280–460 ms after stimulus onset, suggesting easier semantic processing of thematic than taxonomic relationships. Moreover, P600 mean amplitude was significantly increased for taxonomic targets between 520–600 ms, consistent with a greater need for stimulus reevaluation in that condition. These results offer novel evidence in favor of a dissociation between thematic and taxonomic thinking in the early phases of conceptual evaluation.

Taxonomic and thematic semantic systems

Object concepts are critical for nearly all aspects of human cognition, from perception tasks like object recognition, to understanding and producing language, to making meaningful actions. Concepts can have 2 very different kinds of relations: similarity relations based on shared features (e.g., dog-bear), which are called "taxonomic" relations, and contiguity relations based on co-occurrence in events or scenarios (e.g., dog-leash), which are called "thematic" relations. Here, we report a systematic review of experimental psychology and cognitive neuroscience evidence of this distinction in the structure of semantic memory. We propose 2 principles that may drive the development of distinct taxonomic and thematic semantic systems: differences between which features determine taxonomic versus thematic relations, and differences in the processing required to extract taxonomic versus thematic relations. This review brings together distinct threads of behavioral, computational, and neuroscience research on semantic memory in support of a functional and neural dissociation, and defines a framework for future studies of semantic memory. (PsycINFO Database Record

The Temporal Order of Word Presentation Modulates the Amplitudes of P2 and N400 during Recognition of Causal Relations

The processing of causal relations has been constantly found to be asymmetrical once the roles of cause and effect are assigned to objects in interactions. We used a relationship recognition paradigm and recorded electroencephalographic (EEG) signals to explore the neural mechanism underlying the asymmetrical representations of causal relations in semantic memory. The results revealed that the verification of causal relations is faster if two words appear in “cause-effect” order (e.g., virus-epidemic) than if they appear in “effect-cause” order (e.g., epidemic-virus), whereas no such asymmetrical representation was found for the verification of hierarchical relations with reverse orders (e.g., bird-sparrow vs. sparrow-bird) in Experiment 1. Furthermore, the P2 amplitude elicited by “superordinate-subordinate” order was larger than that when in reverse order, whereas the N400 effect elicited by “cause-effect” order was smaller (more positive) than when in reverse order. However, no such asymmetry, as well as P2 and N400 components, were observed when verifying the existence of a general associative relation in Experiment 2. We suggested that the smaller N400 in cause-effect order indicates their increased salience in semantic memory relative to the effect-cause order. These results provide evidence for dissociable neural processes, which are related to role binding, contributing to the generation of causal asymmetry.

The modulation of causal contexts in motion processes judgment as revealed by P2 and P3

The evoked response potential (ERP) procedure was used to investigate the representation of motion processes in different causal contexts, such as the collision of two squares or the repulsion of two magnets with like poles facing. Participants were required to judge whether each movement was plausible according to the causal context depicted by the cover story. Three main differences after the movement of the second object were found. First, the amplitudes at 70-170ms (N1) and 170-370ms (P2) elicited by a no-contact condition were more negative than a contact condition in the square context, whereas larger N1 and more positive amplitudes at 370-670ms were elicited by a no-contact condition in the magnet context. Second, larger P2 and more positive amplitudes at 370-670ms were elicited by inconsistent direction relative to consistent condition in the square context, whereas smaller N1 and more positive amplitudes at 370-670ms were elicited by inconsistent direction in the magnet context. Finally, larger P2 and more negative amplitudes at 370-470ms were elicited by plausible conditions relative to implausible conditions in a square context, whereas larger N1 and more positive amplitudes at 370-670ms were elicited by plausible conditions in the magnet context. These results suggested that the conceptual knowledge with different causal contexts have distinct effects on the judgment of objects interactions.

The Development of Object Function and Manipulation Knowledge: Evidence from a Semantic Priming Study

Object semantics include object function and manipulation knowledge. Function knowledge refers to the goal attainable by using an object (e.g., the function of a key is to open or close a door) while manipulation knowledge refers to gestures one has to execute to use an object appropriately (e.g., a key is held between the thumb and the index, inserted into the door lock and then turned). To date, several studies have assessed function and manipulation knowledge in brain lesion patients as well as in healthy adult populations. In patients with left brain damage, a double dissociation between these two types of knowledge has been reported; on the other hand, behavioral studies in healthy adults show that function knowledge is processed faster than manipulation knowledge. Empirical evidence has shown that object interaction in children differs from that in adults, suggesting that the access to function and manipulation knowledge in children might also differ. To investigate the development of object function and manipulation knowledge, 51 typically developing 8-9-10 year-old children and 17 healthy young adults were tested on a naming task associated with a semantic priming paradigm (190-ms SOA; prime duration: 90 ms) in which a series of line drawings of manipulable objects were used. Target objects could be preceded by three priming contexts: related (e.g., knife-scissors for function; key-screwdriver for manipulation), unrelated but visually similar (e.g., glasses-scissors; baseball bat-screwdriver), and purely unrelated (e.g., die-scissors; tissue-screwdriver). Results showed a different developmental pattern of function and manipulation priming effects. Function priming effects were not present in children and emerged only in adults, with faster naming responses for targets preceded by objects sharing the same function. In contrast, manipulation priming effects were already present in 8-year-olds with faster naming responses for targets preceded by objects sharing the same manipulation and these decreased linearly between 8 and 10 years of age, 10-year-olds not differing from adults. Overall, results show that the access to object function and manipulation knowledge changes during development by favoring manipulation knowledge in childhood and function knowledge in adulthood.

Thematic knowledge, artifact concepts, and the left posterior temporal lobe: Where action and object semantics converge

Converging evidence supports the existence of functionally and neuroanatomically distinct taxonomic (similarity-based; e.g., hammer-screwdriver) and thematic (event-based; e.g., hammer-nail) semantic systems. Processing of thematic relations between objects has been shown to selectively recruit the left posterior temporoparietal cortex. Similar posterior regions have also been shown to be critical for knowledge of relationships between actions and manipulable human-made objects (artifacts). Based on the hypothesis that thematic relationships for artifacts rely, at least in part, on action relationships, we assessed the prediction that the same regions of the left posterior temporoparietal cortex would be critical for conceptual processing of artifact-related actions and thematic relations for artifacts. To test this hypothesis, we evaluated processing of taxonomic and thematic relations for artifacts and natural objects as well as artifact action knowledge (gesture recognition) abilities in a large sample of 48 stroke patients with a range of lesion foci in the left hemisphere. Like control participants, patients identified thematic relations faster than taxonomic relations for artifacts, whereas they identified taxonomic relations faster than thematic relations for natural objects. Moreover, response times (RTs) for identifying thematic relations for artifacts selectively predicted performance in gesture recognition. Whole brain Voxel-based Lesion-Symptom Mapping (VLSM) analyses and Region of Interest (ROI) regression analyses further demonstrated that lesions to the left posterior temporal cortex, overlapping with LTO and visual motion area hMT+, were associated both with relatively slower RTs in identifying thematic relations for artifacts and poorer artifact action knowledge in patients. These findings provide novel insights into the functional role of left posterior temporal cortex in thematic knowledge, and suggest that the close association between thematic relations for artifacts and action representations may reflect their common dependence on visual motion and manipulation information.

Impact of action primes on implicit processing of thematic and functional similarity relations: evidence from eye-tracking

The aim of this study was to specify the role of action representations in thematic and functional similarity relations between manipulable artifact objects. Recent behavioral and neurophysiological evidence indicates that while they are all relevant for manipulable artifact concepts, semantic relations based on thematic (e.g., saw-wood), specific function similarity (e.g., saw-axe), and general function similarity (e.g., saw-knife) are differently processed, and may relate to different levels of action representation. Point-light displays of object-related actions previously encoded at the gesture level (e.g., "sawing") or at the higher level of action representation (e.g., "cutting") were used as primes before participants identified target objects (e.g., saw) among semantically related and unrelated distractors (e.g., wood, feather, piano). Analysis of eye movements on the different objects during target identification informed about the amplitude and the timing of implicit activation of the different semantic relations. Results showed that action prime encoding impacted the processing of thematic relations, but not that of functional similarity relations. Semantic competition with thematic distractors was greater and earlier following action primes encoded at the gesture level compared to action primes encoded at higher level. As a whole, these findings highlight the direct influence of action representations on thematic relation processing, and suggest that thematic relations involve gesture-level representations rather than intention-level representations.