Prisca Stenneken

Semantic activation in action planning

Four experiments investigated activation of semantic information in action preparation. Participants either prepared to grasp and use an object (e.g., to drink from a cup) or to lift a finger in association with the objects position following a go/no-go lexical-decision task. Word stimuli were consistent to the action goals of the object use (Experiment 1) or to the finger lifting (Experiment 2). Movement onset times yielded a double dissociation of consistency effects between action preparation and word processing. This effect was also present for semantic categorizations (Experiment 3), but disappeared when introducing a letter identification task (Experiment 4). In sum, our findings indicate that action semantics are activated selectively in accordance with the specific action intention of an actor.

Inhibitory effects of first syllable-frequency in lexical decision: an event-related potential study

Electrophysiological correlates of the behaviorally well-documented inhibitory effect of first syllable-frequency during lexical access are presented. In a lexical decision task, response times to words with high-frequency first syllables were longer than those to words with low-frequency first syllables and resulted in more negative event-related potentials (ERPs) in an early time window from 190 ms to 280 ms and in the N400 component. The onset of the observed first syllable-frequency effect was prior to the onset of the effect of lexicality (i.e., the first reliable differentiation in ERP waveforms in response to words and pseudowords, a potential marker of lexical access). The present studys results support Barber et al.s [Neuroreport 15 (2004) 545] notion of the prelexical nature of the first syllable-frequency effect by (A) providing evidence for electrophysiological correlates of first syllable-frequency in another, non-Romance orthography (i.e., German), (B) relating the onset of the first syllable-frequency effect to the onset of the lexicality effect and (C) strengthening this pattern of results by means of a novel item-based analysis of ERP data. Implications of the prelexical nature of the inhibitory first syllable-frequency effect for computational models of reading, specifically for Ans et al.s [Psychol. Rev. 105 (1998) 678] multiple-trace memory (MTM) model of reading are discussed.

The effect of sensory feedback on the timing of movements: Evidence from deafferented patients

The role of sensory feedback in the control of movements was investigated in two deafferented patients with complete loss of cutaneous touch and movement/position sense below the neck and two control groups of different ages. In a synchronized repetitive finger-tapping task in time with a regular auditory pacing signal, the deafferented participants showed a strong influence of extrinsic feedback. In contrast to controls who demonstrated a typical asynchrony between their taps and the pacing signal in all feedback conditions, the deafferented participants, with auditory feedback and visual monitoring, showed no asynchrony between finger taps and the pacing signal. These findings support the view that sensory information plays a crucial role in the anticipatory timing of movements.

Sublexical frequency measures for orthographic and phonological units in German

Many recent studies have demonstrated the influence of sublexical frequency measures on language processing, or called for controlling sublexical measures when selecting stimulus material for psycholinguistic studies (Aichert & Ziegler, 2005). The present study discusses which measures should be controlled for in what kind of study, and presents orthographic and phonological syllable, dual unit (bigram and biphoneme) and single unit (letter and phoneme) type and token frequency measures derived from the lemma and word form corpora of the CELEX lexical database (Baayen, Piepenbrock, & Gulikers, 1995). Additionally, we present the SUBLEX software as an adaptive tool for calculating sublexical frequency measures and discuss possible future applications. The measures and the software can be downloaded at www.psychonomic.org.

Associated or dissociated effects of syllable frequency in lexical decision and naming.

Most empirical work investigating the role of syllable frequency in visual word recognition has focused on the Spanish language, in which syllable frequency seems to produce a classic dissociation: inhibition in lexical decision tasks but facilitation in naming. In the present study, two experiments were run in German, using identical stimulus materials, in a lexical decision task and a naming task. In both tasks, there was an inhibitory effect for words with a high-frequency first syllable. This pattern of results, suggesting a stronger weight of lexical access in the naming process in German than in Spanish, is discussed with regard to the issue of stress assignment in the two languages and within the framework of word production models. Items, mean response latencies, and accuracy rates per item for both experiments can be downloaded from www.psychonomic.org/archive.

Syllable structure and sonority in language inventory and aphasic neologisms

Phonological theories have raised the notion of a universally preferred syllable type which is defined in terms of its sonority structure (e.g., ). Empirical evidence for this notion has been provided by distributional analyses of natural languages and of language acquisition data, and by aphasic speech error analyses. The present study investigates frequency distributions of syllable types in German, which allows for a rather complex syllable structure, and in neologistic utterances of a German speaking jargon aphasic. The findings suggest that the sonority structure of the patients neologisms is generally in accordance with the notion of theoretically preferred syllables. Moreover, comparative analyses suggest that the predominance of the preferred syllable type is especially pronounced in the aphasic data. On the basis of these findings, the influence of sonority in impaired phonological lexical processing is discussed.

Timing of bimanual movements and deafferentation: implications for the role of sensory movement effects.

In a repetitive tapping task, the within-hand variability of intertap intervals is reduced when participants tap with both hands instead of single-handedly. This bimanual advantage has been attributed to timer as opposed to motor variance (according to the Wing-Kristofferson model; Helmuth and Ivry 1996) and related to the additional sensory consequences of the movement of the extra hand in the bimanual case (Drewing et al. 2002). In the present study the effect of sensory feedback of the movement on this advantage was investigated by comparing the results of a person (IW) deafferented below the neck with those of age-matched controls. IW showed an even more pronounced bimanual advantage than controls, suggesting that the bimanual advantage is not due to actual sensory feedback. These results support another hypothesis, namely that bimanual timing profits from the averaging of different central control signals that relate to each effector’s movements.

Differences in Noun and Verb Processing in Lexical Decision Cannot be Attributed to Word Form and Morphological Complexity Alone

It has been suggested that the effect of word category in noun and verb processing reflects typical word class properties, which can be characterized in terms of semantic as well as syntactic and morphological features. The present study is aimed at differentiating and discussing the relative contribution of these aspects with a main focus on syntactic and morphological processing. Experiment 1 established a processing advantage for nouns in German visual lexical decision, using nouns denoting biological and man-made objects as compared to transitive and intransitive verbs. Experiment 2 showed that the noun advantage persisted even when the morphological differences between word categories were reduced by using identical suffixes in nouns and verbs. Overall results suggest that the processing differences cannot be reduced to variables such as frequency, word form, or morphological complexity. Reaction time differences between transitive and intransitive verbs strengthen the role of syntactic information. In line with previous accounts the observed effects are discussed in terms of a category-specific combination of linguistic parameters.

Exploring the Neural Basis of Real-Life Joint Action: Measuring Brain Activation during Joint Table Setting with Functional Near-Infrared Spectroscopy

Many every-day life situations require two or more individuals to execute actions together. Assessing brain activation during naturalistic tasks to uncover relevant processes underlying such real-life joint action situations has remained a methodological challenge. In the present study, we introduce a novel joint action paradigm that enables the assessment of brain activation during real-life joint action tasks using functional near-infrared spectroscopy (fNIRS). We monitored brain activation of participants who coordinated complex actions with a partner sitting opposite them. Participants performed table setting tasks, either alone (solo action) or in cooperation with a partner (joint action), or they observed the partner performing the task (action observation). Comparing joint action and solo action revealed stronger activation (higher [oxy-Hb]-concentration) during joint action in a number of areas. Among these were areas in the inferior parietal lobule (IPL) that additionally showed an overlap of activation during action observation and solo action. Areas with such a close link between action observation and action execution have been associated with action simulation processes. The magnitude of activation in these IPL areas also varied according to joint action type and its respective demand on action simulation. The results validate fNIRS as an imaging technique for exploring the functional correlates of interindividual action coordination in real-life settings and suggest that coordinating actions in real-life situations requires simulating the actions of the partner.

The human execution/observation matching system investigated with a complex everyday task: a functional near-infrared spectroscopy (fNIRS) study.

The investigation of brain areas involved in the human execution/observation matching system (EOM) has been limited to restricted motor actions when using common neuroimaging techniques such as functional magnetic resonance imaging (fMRI). A method which overcomes this limitation is functional near-infrared spectroscopy (fNIRS). In the present study, we explored the cerebral responses underlying action execution and observation during a complex everyday task. We measured brain activation of 39 participants during the performance of object-related reaching, grasping and displacing movements, namely setting and clearing a table, and observation of the same task from different perspectives. Observation of the table-setting task activated parts of a network matching those activated during execution of the task. Specifically, observation from an egocentric perspective led to a higher activation in the inferior parietal cortex than observation from an allocentric perspective, implicating that the viewpoint also influences the EOM during the observation of complex everyday tasks. Together these findings suggest that fNIRS is able to overcome the restrictions of common imaging methods by investigating the EOM with a naturalistic task.