Web‐based stimulus preference assessment and reinforcer assessment for videos

This study replicated and extended the use of a web‐based multiple‐stimulus‐without‐replacement preference assessment (Curiel, Curiel, Li, Deochand, & Poling, 2018) by adding a web‐based single‐operant reinforcer assessment. Five adults diagnosed with autism spectrum disorder participated in this study. The web‐based program identified preference hierarchies for 4 of the 5 participants, and the single‐operant reinforcer assessment confirmed that the highly preferred videos functioned as reinforcers. Advantages of computer‐based stimulus preference and reinforcer assessments are discussed.     

Overcoming ego depletion: the influence of exemplar priming on self‐control performance

Self‐regulation research suggested that active self‐control depends on a limited resource. Therefore the capacity for self‐control is lower among people who already exercised control, a phenomenon labelled as ego depletion. This experiment examines whether priming of a persistent person exemplar may help to overcome ego depletion. Half of the participants engaged in a demanding self‐control task (solving extremely difficult labyrinths) whereas the other half took part in a task that demanded little self‐control (solving easy labyrinths). Then, half of the participants received a person exemplar prime related to persistence; the other half received a neutral prime. Finally, participants' persistence on a subsequent self‐control task (squeezing a handgrip) was measured. The effect of a person exemplar prime on a subsequent self‐control task depended on initial self‐control demands. Participants who exercised high initial self‐control and were then presented with a persistent exemplar prime showed assimilation. Their handgrip persistence was higher than the persistence of participants who received a neutral prime. Under conditions of low initial self‐control the opposite pattern was found. A persistent person prime resulted in contrast and resulted in lower handgrip performance as compared to those who received a neutral prime. Copyright © 2006 John Wiley & Sons, Ltd.     

The ADP-IV questionnaire: differential validity and concordance with the semi-structured interview

The Assessment of DSM-IV Personality Disorders questionnaire (ADP-IV) is a self-report measure of the DSM-IV Axis II personality disorders (PDs). The ADP-IV assesses for each DSM-IV criterion its typicality as well as the accompanying distress and impairment. This study investigates two important aspects of the construct validity of the ADP-IV: (a) the differential validity (i.e., the ability to differentiate between a sample of the general Flemish population ( n = 659) and a sample of psychiatric inpatients ( n = 487) with a high prevalence of clinical PD diagnoses, and patients with and without a PD in the psychiatric sample; (b) the convergent validity with the SCID-II semi-structured interview in a population of psychiatric inpatients ( n = 59). The results indicate a good differential validity: the dimensional scales and the categorical measures discriminated well between both groups and between patients with and without a PD diagnosis in the psychiatric sample. Concerning the concordance with the SCID-II, a decent level of agreement is exemplified by a correlation of.67 between the dimensional total scores of both instruments and by kappa coefficients for an "any" Axis II diagnosis at the.50 level. In conclusion, the results indicate that the ADP-IV is an efficient method for assessing PD in dimensional and categorical ways.     

Comparative and categorical spatial judgments in the monkey: “high” and “low”

Adult human subjects can classify the height of an object as belonging to either of the high or low categories by utilizing an abstract concept of midline that divides the vertical dimension into two halves. Children lack this abstract concept of midline, do not have a sense that these categories are directional opposites, and their categorical and comparative usages of high(er) or low(er) are restricted to the corresponding poles. We investigated the abilities of a rhesus monkey to perform categorical judgments in space. We were also interested in the presence of the congruity effect (a decrease in response time when the objects compared are closer to the category pole) in the monkey. The presence of this phenomenon in the monkey would allow us to relate the behavior of the animal to the two major competing hypotheses that have been suggested to explain the congruity effect in humans: the analog and semantic models. The monkey was trained in delayed match-to-sample tasks in which it had to categorize objects as belonging to either a high or low category. The monkey was able to generate an abstract notion of midline in a fashion similar to that of adult human subjects. The congruity effect was also present in the monkey. These findings, taken together with the notion that monkeys are not considered to think in propositional terms, may favor an analog comparison model in the monkey.     

Spared anterograde memory for shock-probe fear conditioning after inactivation of the amygdala

Previous studies have shown that amygdala lesions impair avoidance of an electrified probe. This finding has been interpreted as indicating that amygdala lesions reduce fear. It is unclear, however, whether amygdala-lesioned rats learn that the probe is associated with shock. If the lesions prevent the formation of this association, then pretraining reversible inactivation of the amygdala should impair both acquisition and retention performance. To test this hypothesis, the amygdala was inactivated (tetrodotoxin; TTX; 1 ng/side) before a shock-probe acquisition session, and retention was tested 4 d later. The data indicated that, compared with rats infused with vehicle, rats infused with TTX received more shocks during the acquisition session, but more importantly, were not impaired on the retention test. In Experiment 2, we assessed whether the spared memory on the retention test was caused by overtraining during acquisition. We used the same procedure as in Experiment 1, with the exception that the number of shocks the rats received during the acquisition session was limited to four. Again the data indicated that amygdala inactivation did not impair performance on the retention test. These results indicate that amygdala inactivation does not prevent the formation of an association between the shock and the probe and that shock-probe deficits during acquisition likely reflect the amygdala's involvement in other processes.     

Paradoxical facilitation of attention in healthy humans

Transcranial magnetic stimulation (TMS)-induced virtual lesions in healthy subjects can be used to test neurofunctional models of disease. The interhemispheric rivalry model of heminglect is well suited for such investigations, as simple predictions derived from clinical data can be tested without the caveats normally associated with lesion studies. One of these predictions is that release from contralateral inhibition should lead to increased parietal responsiveness, which, in turn, would enhance spatial attention. Here, we detail studies showing TMS-induced paradoxical functional facilitation of attention in healthy individuals and highlight their contribution to the understanding and treatment of neglect syndromes.