The Embodied Statistician

How do infants, children, and adults learn grammatical rules from the mere observation of grammatically structured sequences? We present an embodied hypothesis that (a) people covertly imitate stimuli; (b) imitation tunes the particular neuromuscular systems used in the imitation, facilitating transitions between the states corresponding to the successive grammatical stimuli; and (c) the discrimination between grammatical and ungrammatical stimuli is based on differential ease of imitation of the sequences. We report two experiments consistent with the embodied account of statistical learning. Experiment 1 demonstrates that sequences composed of stimuli imitated with different neuromuscular systems were more difficult to learn compared to sequences imitated within a single neuromuscular system. Experiment 2 provides further evidence by showing that selectively interfering with the tuned neuromuscular system while attempting to discriminate between grammatical and ungrammatical sequences disrupted performance only on sequences imitated by that particular neuromuscular system. Together these results are difficult for theories postulating that grammatical rule learning is based primarily on abstract statistics representing transition probabilities

Evidence for auditory temporal distinctiveness: Modality effects in order and frequency judgments.

[EN]Two new, long-lasting phenomena involving modality of stimulus presentation are documented. In one series of experiments we investigated effects of modality of presentation on order judgments. Order judgments for auditory words were more accurate than order judgments for visual words at both the beginning and the end of lists, and the auditory advantage increased with the temporal separation of the successive items. A second series of experiments investigated effects of modality on estimates of presentation frequency. Frequency estimates of repeated auditory words exceeded frequency estimates of repeated visual words. The auditory advantage increased with frequency of presentation, and this advantage was not affected by the retention interval. These various effects were taken as support for a temporal coding assumption, that auditory presentation produces a more accurate encoding of time of presentation than does visual presentation.National Science Foundation Grant BNS 84-1630

Changing environmental context does not reliably affect memory

[EN]Most current theories of human memory propose that context, defined here as the time and place at which an event was experienced, forms an integral feature ofthe mnemonic representa tion of events. One way of investigating context is by manipulating the environmental context (which typically means the room in which the experiment takes place). The predominant result ofthis manipulation reported in the literature has been consistent with theory: Memory perfor mance is better when the learning and testing environments are the same than when they differ. This article reports eight experiments that in aggregate challenge the reliability of this same context advantage. Experiment 1 reported a failure to obtain a same-context advantage. Experi ments 2-7 investigated various features of the design that might have reduced the effect. None of these experiments produced a reliable same-context advantage, Experiment 8 repeated the methodology of a published report of a same-context advantage with more than double the num ber of subjects, but failed to replicate the effect. An analysis of features of the experiments led to two suggestions for future investigations of the effects of changes in environmental context on memory

Factors Influencing Cerebral Plasticity in the Normal and Injured Brain

An important development in behavioral neuroscience in the past 20 years has been the demonstration that it is possible to stimulate functional recovery after cerebral injury in laboratory animals. Rodent models of cerebral injury provide an important tool for developing such rehabilitation programs. The models include analysis at different levels including detailed behavioral paradigms, electrophysiology, neuronal morphology, protein chemistry, and epigenetics. A significant challenge for the next 20 years will be the translation of this work to improve the outcome from brain injury and disease in humans. Our goal in the article will be to synthesize the multidisciplinary laboratory work on brain plasticity and behavior in the injured brain to inform the development of rehabilitation programs

Top-Down and Bottom-Up Contributions to Understanding Sentences Describing Objects in Motion

Theories of embodied language comprehension propose that the neural systems used for perception, action, and emotion are also engaged during language comprehension. Consistent with these theories, behavioral studies have shown that the comprehension of language that describes motion is affected by simultaneously perceiving a moving stimulus (Kaschak et al., 2005). In two neuroimaging studies, we investigate whether comprehension of sentences describing moving objects activates brain areas known to support the visual perception of moving objects (i.e., area MT/V5). Our data indicate that MT/V5 is indeed selectively engaged by sentences describing objects in motion toward the comprehender compared to sentences describing visual scenes without motion. Moreover, these sentences activate areas along the cortical midline of the brain, known to be engaged when participants process self-referential information. The current data thus suggest that sentences describing situations with potential relevance to one's own actions activate both higher-order visual cortex as well brain areas involved in processing information about the self. The data have consequences for embodied theories of language comprehension: first, they show that perceptual brain areas support sentential-semantic processing. Second the data indicate that sensory-motor simulation of events described through language are susceptible to top-down modulation of factors such as relevance of the described situation to the self

Putting words in perspective

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Retrieving Against the Flow: Incoherence Between Optic Flow and Movement Direction Has Little Effect on Memory for Order

[EN]Research from multiple areas in neuroscience suggests a link between self-locomotion and memory. In two free recall experiments with adults, we looked for a link between (a) memory, and (b) the coherence of movement and optic flow. In both experiments, participants heard lists of words while on a treadmill and wearing a virtual reality (VR) headset. In the first experiment, the VR scene and treadmill were stationary during encoding. During retrieval, all participants walked forward, but the VR scene was stationary, moved forward, or moved backwards. In the second experiment, during encoding all participants walked forward and viewed a forward-moving VR scene. During retrieval, all participants continued to walk forward but the VR scene was stationary, forward-moving, or backward-moving. In neither experiment was there a significant difference in the amount recalled, or output order strategies, attributable to differences in movement conditions. Thus, any effects of movement on memory are more limited than theories of hippocampal function and theories in cognitive psychology anticipate

Embodied Processing at Six Linguistic Granularity Levels: A Consensus Paper

Language processing is influenced by sensorimotor experiences. Here, we review behavioral evidence for embodied and grounded influences in language processing across six linguistic levels of granularity. We examine (a) sub-word features, discussing grounded influences on iconicity (systematic associations between word form and meaning); (b) words, discussing boundary conditions and generalizations for the simulation of color, sensory modality, and spatial position; (c) sentences, discussing boundary conditions and applications of action direction simulation; (d) texts, discussing how the teaching of simulation can improve comprehension in beginning readers; (e) conversations, discussing how multi-modal cues improve turn taking and alignment; and (f) text corpora, discussing how distributional semantic models can reveal how grounded and embodied knowledge is encoded in texts. These approaches are converging on a convincing account of the psychology of language, but at the same time, there are important criticisms of the embodied approach and of specific experimental paradigms. The surest way forward requires the adoption of a wide array of scientific methods. By providing complimentary evidence, a combination of multiple methods on various levels of granularity can help us gain a more complete understanding of the role of embodiment and grounding in language processing