Simultaneous classical conditioning of two effector systems

The experiment reported here was an attempt to develop an experimental procedure for independent classical conditioning of two different response systems, the skin conductance response (SCR) and the eyelid response. In a differential conditioning design with human subjects (N=50) two different unconditioned stimuli were used, a white noise (US₁) and an airpuff (US₂). Two conditioned stimuli (CS₁₁ and CS₁₂) were paired with US₁, and two other CSs (CS₂₁ and CS₂₂) were paired with US₂. A special trial architecture was used to accomplish measurement of both anticipatory SCR and eyelid responses during each trial. Significant eyelid differentiation as well as significant SCR (especially second interval responses) differentiation developed.     

Eyeblink startle responses in spider phobies before and after treatment: A pilot study

Before and after treatment, acoustic probes eliciting eyeblink startles were presented to 41 female spider phobies during a behavioral approach test (BAT). During this test, subjects pulled a glass jar containing a live spider as nearby as they normally would tolerate. In order to obtain baseline startles, the subjects also carried out a BAT with a basket containing attractive food items. Startle responses were found to be relatively larger during the spider BAT than during the food BAT. This difference in relative magnitude decreased as a result of one-session treatment. The startle response appeared to be relatively independent of other outcome measures (i.e., Spider Questionnaire, BAT, and heart rate). Taken together, the results sustain findings previously reported by Lang and co-workers.     

Affixal homonymy triggers full-form storage, even with inflected words, even in a morphologically rich language

This paper investigates whether affixal homonymy, the phenomenon that one affix form serves two or more semantic/syntactic functions, affects lexical processing of inflected words in a similar way for a morphologically rich language such as Finnish as for morphologically restricted languages such as Dutch and English. For the latter two languages, there is evidence that affixal homonymy triggers full-form storage for inflected words (Bertram, R., Schreuder, R., and Baayen, R. H. (in press). The balance of storage and computation in morphological processing: the role of word formation type, affixal homonymy, and productivity. Journal of Experimental Psychology: Learning, Memory, and Cognition; Sereno and Jongman (1997). Processing of English inflectional morphology. Memory and Cognition, 25, 425-437). Two visual lexical decision experiments show the same pattern for Finnish. Apparently, the substantially richer morphology in Finnish does not prevent full-form storage for inflected words when the affix is homonymic.     

Muster früher Traumatisierung und die Effekte stationärer Psychotherapie

Early traumatic experiences of neglect, physical and sexual abuse in adult patients undergoing inpatient psychotherapeutic treatment were retrospectively assessed. Associations between these three forms of trauma and with patient gender were analyzed. The effects of early traumatization in general, gender and patterns of specific experiences on the symptom level, level of everyday functioning and treatment outcome were also investigated. A total of 191 patients in a psychosomatic psychotherapy ward of a university hospital were assessed using standardized questionnaires on sociodemographic and clinical variables on admission and at discharge. The type and extent of early traumatization before the age of 18 years were estimated after the initial interview from standardized reports of the therapists. The results indicate that the probability of being exposed to one of the traumatic experiences under study are not independent of each other. Furthermore, female patients were victims of sexual abuse and neglect more often than males. Compared to non-traumatized patients, trauma victims exhibited more psychological symptoms in the symptom checklist 90 revised (SCL-90-R) and a lower level of functioning according to the global assessment of functioning (GAF) but achieved a comparable relative benefit from treatment. Sexual abuse (SCL-90-R and GAF) and neglect (SCL-90-R only) affected the levels of impairment on admission and at discharge in a similar way; however, only weak evidence for differential effects of trauma patterns on therapy outcomes was found. Methodological limitations of the present approach and implications for the design of inpatient psychotherapeutic interventions in adult patients with early traumatic experiences are discussed.     

An fMRI study of working memory for schematic facial expressions

Functional magnetic resonance imaging (fMRI) was used to examine neuronal activation in relation to increasing working memory load in an n-back task, using schematic drawings of facial expressions and scrambled drawings of the same facial features as stimuli. The main objective was to investigate whether working memory for drawings of facial features would yield specific activations compared to memory for scrambled drawings based on the same visual features as those making up the face drawings. fMRI-BOLD responses were acquired with a 1.5 T Siemens MR scanner while subjects watched the facial drawings alternated with the scrambled drawings, in a block-design. Subjects had to hold either 1 or 2 items in working memory. We found that the main effect of increasing memory load from one to two items yielded significant activations in a bilaterally distributed cortical network consisting of regions in the occipitotemporal cortex, the inferior parietal lobule, the dorsolateral prefrontal cortex, supplementary motor area and the cerebellum. In addition, we found a memory load x drawings interaction in the right inferior frontal gyrus in favor of the facial drawings. These findings show that working memory is specific for facial features which interact with a general cognitive load component to produce significant activations in prefrontal regions of the brain.     

The time-course of morphological constraints: evidence from eye-movements during reading

Lexical compounds in English are constrained in that the non-head noun can be an irregular but not a regular plural (e.g. mice eater vs. *rats eater), a contrast that has been argued to derive from a morphological constraint on modifiers inside compounds. In addition, bare nouns are preferred over plural forms inside compounds (e.g. mouse eater vs. mice eater), a contrast that has been ascribed to the semantics of compounds. Measuring eye-movements during reading, this study examined how morphological and semantic information become available over time during the processing of a compound. We found that the morphological constraint affected both early and late eye-movement measures, whereas the semantic constraint for singular non-heads only affected late measures of processing. These results indicate that morphological information becomes available earlier than semantic information during the processing of compounds.     

Trait dissociation and commission errors in memory reports of emotional events

In 2 studies we examined whether trait dissociation is related to spontaneous commission errors (reports of events that did not occur) in free recall of emotional events. We also explored whether the functional locus of the dissociation-commission link is related to repeated retrieval or shallow encoding. In Experiment 1 participants were exposed to a staged incident and were repeatedly asked to add more information to their written accounts of the event. Dissociation levels were related to commission errors, indicating that people who report many dissociative experiences tend to make more commission errors. However, it was not the case that the overall increase in commission errors over successive retrieval attempts was typical for high dissociative participants. In Experiment 2 participants saw a video fragment of a severe car accident. During the video, half the participants performed a dual task, and the other half did not. Participants performing the dual task made more commission errors than controls, but this effect was not more pronounced in those with high trait dissociation scores. These studies show that there is a link between dissociation and spontaneous commission errors in memory reports of emotional events, but the functional locus of this link remains unclear.     

Chronic oral methylphenidate induces post-treatment impairment in recognition and spatial memory in adult rats

Recent pre-clinical research has indicated that chronic treatment with methylphenidate (Ritalin^®) in young animals can result in lasting and potentially detrimental alterations in brain function that can persist into adulthood. Chronic methylphenidate-induced neuronal alterations may result in behavior and cognitive deficits that include increases in behavioral responses and impairment in recognition memory. This study compared the cognitive consequences following chronic treatment with two doses (5 and 10 mg/kg) of methylphenidate on recognition and spatial memory in adult male Long-Evans rats using an established oral dosing procedure. The animals were then tested in the Object Recognition test at 14 days post treatment and the Object Placement test at 21 days post treatment. The results indicate that repeated exposure to oral methylphenidate impaired the performance of rats in these tests. The current findings add to recent research demonstrating negative consequences in rats pre-treated with methylphenidate, and extend previous findings to include deficits in spatial recognition memory.