Hands-on false memories: a combined study with distributional semantics and mouse-tracking

Visual experience modulates the sensitivity to the distributional history of words in natural language

Different experiential traces (i.e., linguistic, motor, and perceptual) are likely contributing to the organization of human semantic knowledge. Here, we aimed to address this issue by investigating whether visual experience may affect the sensitivity to distributional priors from natural language. We conducted an independent reanalysis of data from Bottini et al., in which early blind and sighted participants performed an auditory lexical decision task. Since previous research has shown that semantic neighborhood density-the mean distance between a target word and its closest semantic neighbors-can influence performance in lexical decision tasks, we investigated whether vision may alter the reliance on this semantic index. We demonstrate that early blind participants are more sensitive to semantic neighborhood density than sighted participants, as indicated by the significantly faster response times for words with higher levels of semantic neighborhood density shown by the blind group. These findings suggest that an early lack of visual experience may lead to enhanced sensitivity to the distributional history of words in natural language, deepening in turn our understanding of the strict interplay between linguistic and perceptual experience in the organization of conceptual knowledge.

Predicting Hand Movements With Distributional Semantics: Evidence From Mouse-Tracking

Although mouse-tracking has been taken as a real-time window on different aspects of human decision-making processes, whether purely semantic information affects response conflict at the level of motor output as measured through mouse movements is still unknown. Here, across two experiments, we investigated the effects of semantic knowledge by predicting participants' performance in a standard keyboard task and in a mouse-tracking task through distributional semantics, a usage-based modeling approach to meaning. In Experiment 1, participants were shown word pairs and were required to perform a two-alternative forced choice task selecting either the more abstract or the more concrete word, using standard keyboard presses. In Experiment 2, participants performed the same task, yet this time response selection was achieved by moving the computer mouse. Results showed that the involvement of semantic components in the task at hand is observable using both standard reaction times (Experiment 1) as well as using indexes extracted from mouse trajectories (Experiment 2). In particular, mouse trajectories reflected the response conflict and its temporal evolution, with a larger deviation for increasing word semantic relatedness. These findings support the validity of mouse-tracking as a method to detect deep and implicit decision-making features. Additionally, by demonstrating that a usage-based model of meaning can account for the different degrees of cognitive conflict associated with task achievement, these findings testify the impact of the human semantic memory on decision-making processes.

The temporal development of memory processes in source monitoring: An investigation with mouse tracking

The present study investigated whether we first remember an item (e.g., a word itself) and then its source (e.g., position on the screen) or whether the retrieval of item and source information can (partially) overlap. Participants were tested on the source either in immediate sequence to item recognition (as standard in source-monitoring research) or following as a separate block after full completion of the item recognition test to separate these processes in time, providing a baseline. Using the mouse-tracking procedure during the item and source tests, we analyzed how item and source decisions unfolded qualitatively over time. Despite no significant difference in the aggregated trajectory curvatures, more thorough analyses based on the individual trajectories revealed differences across the test formats. In the standard format, trajectories were less curved in the source than in the item test. In contrast, in the blocked format, this difference was in the other direction with source showing more curved trajectories than item. Alternative interpretations of mouse-trajectory curvatures on the source-monitoring paradigm and what their difference may imply for item and source processing are discussed.

Individual differences in theory of mind correlate with the occurrence of false memory: A study with the DRM task

Although long-term memory and Theory of Mind (ToM) are closely related across the whole lifespan, little is known about the relationship between ToM and semantic memory. Clinical studies have documented the co-occurrence of ToM impairments and semantic memory abnormalities in individuals with autism or semantic dementia. However, to date, no study has directly investigated the existence of a relationship between ToM and semantic memory in the typical population. We addressed this gap on a sample of 103 healthy adults (M age = 22.96 years; age range = 19-35 years). Participants completed a classical false memory task tapping on semantic processes, the Deese-Roediger-McDermott (DRM) task, and two ToM tasks, the Triangles and the Reading the Mind in the Eyes task. They also completed the vocabulary scale from the Wechsler Adult Intelligence Scale. Results showed that participants' semantic performance in the DRM task was significantly related to that in the Triangles task. Specifically, the higher participants' ToM in the Triangles task, the higher participants' reliance on semantic memory while making false memories in the DRM task. Our findings are consistent with the Fuzzy Trace Theory and the Weak Central Coherence account and suggest that a (partially) common cognitive process responsible for global versus detailed-focus information processing could underlie these two abilities.