The Role of Action Representations in Thematic Object Relations

Abstract

A number of studies have explored the role of associative/event-based (thematic) and categorical (taxonomic) relations in the organization of object representations. Recent evidence suggests that thematic information may be particularly important in determining relationships between manipulable artifacts. However, although sensorimotor information is on many accounts an important component of manipulable artifact representations, little is known about the role that action may play during the processing of semantic relationships (particularly thematic relationships) between multiple objects. In this study, we assessed healthy and left hemisphere stroke participants to explore three questions relevant to object relationship processing. First, we assessed whether participants tended to favor thematic relations including action (Th+A, e.g., wine bottle-corkscrew), thematic relationships without action (Th-A, e.g., wine bottle-cheese), or taxonomic relationships (Tax, e.g., wine bottle-water bottle) when choosing between them in an association judgment task with manipulable artifacts. Second, we assessed whether the underlying constructs of event relatedness, action relatedness, and categorical relatedness determined the choices that participants made. Third, we assessed the hypothesis that degraded action knowledge and/or damage to temporo-parietal cortex, a region of the brain associated with the representation of action knowledge, would reduce the influence of action on the choice task. Experiment 1 showed that explicit ratings of event, action, and categorical relatedness were differentially predictive of healthy participants' choices, with action relatedness determining choices between Th+A and Th-A associations above and beyond event and categorical ratings. Experiment 2 focused more specifically on these Th+A vs. Th-A choices and demonstrated that participants with left temporo-parietal lesions, a brain region known to be involved in sensorimotor processing, were less likely than controls and tended to be less likely than patients with lesions sparing that region to use action relatedness in determining their choices. These data indicate that action knowledge plays a critical role in processing of thematic relations for manipulable artifacts.

Sensory and semantic activations evoked by action attributes of manipulable objects: Evidence from ERPs

“…These differences may help explain the N400 scalp distributions that differed somewhat across the studies (ranging from frontal-central in, e.g., van Elk et al, 2010 to more clearly frontal, as in the current study). More generally, however, the relatively anterior N400 action-related priming effects seen in the present study and related previous studies suggest that access to action semantics (Bach et al, 2009; van Elk et al, 2008, 2010; also see Leshinskaya and Caramazza, 2016 for a discussion) may differ from access to semantic information with weaker relationships to sensory-motor attributes, such as seen in the taxonomic conditions here (see also Kalénine and Buxbaum, 2016; Tsagkaridis et al, 2014). 3 …”

Looking to recognise: the pre-eminence of semantic over sensorimotor processing in human tool use

“…In both experiments, we used object-tool pairs that were thematically consistent or inconsistent. Notably, increasing evidence from studies using thematically related vs. unrelated pairs of objects suggests an involvement of the posterior parieto-temporal cortex (specifically, the temporo-parietal junction, the inferior parietal lobe, and the middle and superior temporal gyri) in objects' thematic relations processing [60][61][62][63] . Moreover, an increased left occipital cortex activation (ventral stream) has been reported when objects are correctly positioned for action, while the anterior regions of the dorsal stream (e.g., supplementary motor area) have been reported to be activated when the task required an action decision but objects were not in the correct position for the action 36 .…”

Taxonomic and thematic semantic systems.

“…This finding was further supported by converging evidence from two studies of individuals with left-hemisphere stroke. The first found that temporoparietal lesions specifically impaired sensitivity to thematic relations that involve action, such as wine bottle – corkscrew (Tsagkaridis, Watson, Jax, & Buxbaum, 2014). The second showed a behavioral association between recognition of meaningful gestures (action knowledge) and performance on thematic triads, and that this association was mediated by posterior temporal damage (Kalénine & Buxbaum, 2016).…”