Semantic aspects of morphological processing: transparency effects in Serbian

We examined the contribution of semantics to morphological facilitation in the visual lexical decision task at two stimulus onset asynchronies (SOAs) with Serbian materials. Primes appeared in Roman or Cyrillic characters. Targets always were printed in Roman. When primes were presented at an SOA of 250 msec, decision latencies to verbal targets (e.g., VOLIM) showed greatest facilitation after inflectionally (e.g., VOLE) related primes, significantly less after semantically transparent derived primes (e.g., ZAVOLE), and less again after semantically opaque derived primes (e.g., PREVOLE). Latencies after semantically transparent and opaque derived target words did not differ at an SOA of 48 msec. Both were slower than after inflectionally related primes. Stated generally, effects of semantic transparency among derivationally related verb forms were evident at long SOAs, but not at short ones. Under alphabet-alternating conditions, magnitudes of facilitation were greater overall, but the pattern was similar. The outcome suggests that restricted processing time for the prime limits the contribution of semantics to morphological processing and calls into question accounts that posit a task-invariant semantic criterion for morphological decomposition within the lexicon.     

Distinct Neurophysiological Patterns Reflecting Aspects of Syntactic Complexity and Syntactic Repair

Aspects of syntactic complexity and syntactic repair were investigated by comparing the event-related (brain) potentials (ERPs) for sentences of different syntactic complexity to those containing a syntactic violation. Previous research had shown that both aspects of syntactic processing are reflected in a late positivity (P600). Results from the present reading experiment demonstrate, however, that although both processing aspects elicit a late positivity, they are different in distribution. The repair-related positivity preceded by a negativity displayed a centroparietal distribution, whereas the complexity-related positivity showed a frontocentral scalp distribution. These data indicate that the P600 is not a unitary phenomenon. Moreover, the distributional differences strongly suggest that different neural structures underlie the two aspects of processing, namely syntactic repair and syntactic integration difficulties, most evident when processing syntactically complex sentences.     

Discrimination between host songs by brood parasitic brown-headed cowbirds ( Molothrus ater)

Songbirds can learn both to produce and to discriminate between different classes of acoustic stimuli. Varying levels of auditory discrimination may improve the fitness of individuals in certain ecological and social contexts and, thus, selection is expected to mold the cognitive abilities of different species according to the potential benefits of acoustic processing. Although fine-scale auditory discrimination of conspecific songs and calls has been frequently reported for brood parasitic brown-headed cowbirds (Molothrus ater), it remains unclear why and how they perceive differently the songs of their many host species. Using habituation-dishabituation paradigms and measuring behavioral and physiological (heart-rate) responses, we found that captive female cowbirds consistently discriminated between songs of two host species, the song sparrow (Melospiza melodia) and the red-winged blackbird (Agelaius phoeniceus). Playback experiments with stimuli composed of con-specific followed by heterospecific vocalizations in the field also demonstrated discrimination between these heterospecific songs even though cowbirds were not attracted to playbacks of either host species' songs alone. Our results do not directly support a nest-searching function of heterospecific song discrimination by cowbirds and are most consistent with a function of the parasites' avoidance of attacks by their agressive hosts. These data demonstrate discrimination between heterospecific vocalizations by brown-headed cowbirds and add a novel dimension to the already expansive auditory perceptual abilities of brood parasitic species and other songbirds. Electronic Publication     

Prosody-assisted head-driven access to spoken German compounds

Auditory processing of German 2-noun compound words was investigated with 328 participants in 4 experiments by monitoring semantic priming effects of the left constituents of the compound words. The authors demonstrated that there is no primacy of the left constituents in accessing auditorily presented German compound words in the mental lexicon. A clear priming effect of left constituents occurred only for compound words with a transparent right constituent that is the head of compound words in Germanic languages. The data suggest that the access to German compounds in the auditory domain involves 2 temporally overlapping routes: direct and decompositional. The prosodic structure (i.e., the duration) of the first morphemes of compound words appears to be a determining factor for activation of the decompositional route.     

Narcolepsy: pathophysiology and neuropsychological changes

Narcolepsy is now recognized as a distinctive disorder with specific pathophysiology and neurochemical abnormalities. Findings on the role of the neuropeptide hypocretin are opening new avenues of research and new strategies for therapy. Recently, neuropsychological and electrophysiological studies have provided evidence for reduced memory performance on standard memory tests in addition to subjective complaints of forgetfulness which may be related to changes in attentional processing. Further studies are, however, necessary to clarify the neuropsychological profile in narcolepsy. This review focuses on the recent advances in understanding narcolepsy.     

Aggressive and nonaggressive antisocial behavior in adolescence

This study examined whether a distinction between aggressive and nonaggressive antisocial behavior can be empirically verified in a large (254 girls and 254 boys) nonclinical (community) sample of Dutch adolescents between 12 and 18 years old. The results of confirmatory factor analysis for both boys and girls shows that aggressive and nonaggressive antisocial behaviors do not represent a single underlying dimension, but two separate constructs with moderate independence among them. These findings suggest that the conceptualization of adolescent antisocial behavior as a one-dimensional phenomenon is of questionable utility and supports growing evidence that aggressive antisocial behavior is distinct from other forms of antisocial behavior.     

Process dissociation using a guided procedure

A method for achieving process dissociation is described that places less emphasis on participants' understanding and remembering interpretations of test cues than does the standard procedure. The proposed method, called the guided procedure, tests memory with a sequence of two prompts, one requesting word-stem recognition, followed by another for word-stem completion. Inclusion and exclusion conditions are produced by requesting completion of recognized stems to form previously presented or new words, respectively. Estimates of automatic and conscious memory produced by the standard and the guided procedures are compared in studies modeled after Toth, Reingold, and Jacoby (1994). Although not significantly different in many aspects, the outcomes differ in ways that may reflect less reliance on a generate-recognize strategy of participants tested with the guided procedure. Additional measures of memory available only with the guided procedure are presented.     

Versuche über die Grundlagen der räumlichen Orientierung bei der säugenden Ratte

Ohne ZusammenfassungDie Arbeit wurde in kürzerer Fassung am XVI. Internationalen Kongreß für Psychologie in Bonn 1960 unter dem Titel Räumliche Orientierung der gejungten Ratte vorgetragen.     

Differentiating myoclonus from tics

A Myoclonus Versus Tic Checklist facilitates making this vexing differential diagnosis. Although it appears to be a valuable tool for clinical, educational, and research purposes, psychometric characterization of the Myoclonus Versus Tic Checklist is needed.