Demonstration of a socially transmitted flavor aversion in rats? Kuan and Colwill (1997) revisited

In each of three experiments that differed only in procedural detail, observer rats interacted with pairs of conspecific demonstrators, one fed a cocoa-flavored diet (Diet Coc) and the other a cinnamon-flavored diet (Diet Cin). Immediately after both members of a pair of demonstrators had been fed, and 5 min before they interacted with an observer or observers, one of the demonstrators was made ill by intraperitoneal injection with lithium chloride. After interacting with a pair of demonstrators for 15 min, each observer was allowed to choose between Diet Cin and Diet Coc for 22 h. In all three experiments, observer rats consumed as much Diet Cin after interacting simultaneously with both an ill demonstrator that had eaten Diet Cin and a healthy demonstrator that had eaten Diet Coc as after interacting simultaneously with both a healthy demonstrator that had eaten Diet Cin and an ill demonstrator that had eaten Diet Coc. These results raise questions about the generality of Kuan and Colwill’s (1997) demonstration of socially transmitted flavor aversions in Norway rats.     

Maladaptive conflict monitoring as evidence for executive dysfunction in children with chromosome 22q11.2 deletion syndrome

Using an adaptation of the Attentional Networks Test, we investigated aspects of executive control in children with chromosome 22q11.2 deletion syndrome (DS22q11.2), a common but not well understood disorder that produces non-verbal cognitive deficits and a marked incidence of psychopathology. The data revealed that children with DS22q11.2 demonstrated greater difficulty than controls in locating and processing target items in the presence of distracters. Importantly, children with DS22q11.2 showed a deficit in the ability to monitor and adapt to stimulus conflict. These data provide evidence of inadequate conflict adaptation in children with DS22q11.2, a problem that is also present in schizophrenia. The findings of specific executive dysfunction in this group may provide a linkage between particular genetic abnormalities and the development of psychopathology.     

Modeling unipolar depression as a chaotic process

This study inspected the deterministic structure of unipolar depression. Two women self-monitored sadness hourly 10 times a day for 6 months. One woman had a recurrent history of unipolar depression, and the other did not. Data were analyzed by visual inspection, examination of the Fourier transforms of the time plots, and the correlation dimension. Results suggested that in addition to a strong periodic component that existed only within the depressed subject's mood time series, a low-dimensional chaotic process might have been operating. In the nondepressed control subject, no such periodicity or process could be identified. The findings support maladaptive deterministic theories of mood disorders and have implications for the assessment of unipolar depression.     

Timed picture naming: Extended norms and validation against previous studies

Factors affecting word retrieval were compared in a timed picture-naming paradigm for 520 drawings of objects. In prior timed and untimed studies by Snodgrass and Vanderwart (1980) and Snodgrass and Yuditsky (1996), concerns were raised that participants could not reliably name large numbers of items in a single session. We show that reliable results are obtained in a single session for 520 items and validate our method against previous findings by Snodgrass and colleagues for overlapping items. For these items, comparable levels of name agreement and latency are obtained, and we replicate effects of length, frequency, both objective and subjective age of acquisition, and visual complexity on reaction time (RT) and name agreement measures. Name agreement is unaffected by order of presentation, although there is a gradual increase in RTs across the session, requiring use of multiple random orders. Current extensions of our method include cross-linguistic, bilingual, developmental, and neuropsychological studies and comparisons of action naming and object naming.     

Counter-stereotypical impulsivity and violence among African American college men

The study examined the relationship between impulse control and violence in terms of past feelings and acts among African American males enrolled in Historically Black Colleges and Universities. Data were gathered from a sample of 1,874 male undergraduates in eleven colleges and universities with predominantly African-American students. Less than six percent were classified as impulsive, and even less than half of the impulsive males had past feelings and acts of violence. The study offers strategies for impulse control which may help to further minimize incidents of violence on the college campus.     

Adult-child interaction during invasive medical procedures.

Adult-child interactions during stressful medical procedures were investigated in 43 pediatric patients videotaped during a venipuncture procedure in the course of cancer treatment. Relations among six adult behavior categories (explain, distract, command to engage in coping behavior, give control to the child, praise, and criticize/threat/bargain) and three child behavior categories (momentary distress, cry/scream, and cope) were examined using correlational and sequential analysis. Results indicated that adult distraction resulted in increased child coping and reduced momentary distress and crying. Adult explanations, although a likely response to child distress and crying, did not result in a reduction of these behaviors. Attempts to give the child control reduced child crying. Implications for clinical interventions during painful medical procedures are discussed.     

On the status of implicit memory bias in anxiety

The present study evaluated the status of mood congruent memory bias in implicit memory tasks for threat related information. A literature review complemented by three experiments on high and low trait anxiety participants found no implicit memory bias for threat-related information in anxious individuals on either word fragment completion or tachistoscopic word identification tasks. The theoretical implications of these results are discussed.     

Pre-cuing Target Location Reduces Interference but Not Negative Priming from Visual Distractors

Research on visual selective attention has shown that processing of distractors can produce (1) interference with response to a concurrent target, and (2) negative priming of response to a subsequent target. These results support late-selection accounts of attention. However, recent findings demonstrate that when conditions are optimal for attentional focusing, the interference effects are almost entirely eliminated. This result has been interpreted as supporting early-selection accounts. The present study investigates the impact of focusing attention on negative priming in addition to interference effects. In a letter-identification task, reliable interference and negative priming effects were observed from distractors. However, when the location of the target in the prime display was pre-cued, interference effects were significantly reduced, but negative priming effects did not decrease. This pattern of results provides further evidence that the absence of interference is insufficient to determine whether distractors have been semantically processed (Driver & Tipper, 1989).     

Electrophysiological evidence for age effects on sensory memory processing of tonal patterns

In older adults, difficulties processing complex auditory scenes, such as speech comprehension in noisy environments, might be due to a specific impairment of temporal processing at early, automatic processing stages involving auditory sensory memory (ASM). Even though age effects on auditory temporal processing have been well-documented, there is a paucity of research on how ASM processing of more complex tone-patterns is altered by age. In the current study, age effects on ASM processing of temporal and frequency aspects of two-tone patterns were investigated using a passive listening protocol. The P1 component, the mismatch negativity (MMN) and the P3a component of event-related brain potentials (ERPs) to tone frequency and temporal pattern deviants were recorded in younger and older adults as a measure of auditory event detection, ASM processing, and attention switching, respectively. MMN was elicited with smaller amplitude to both frequency and temporal deviants in older adults. Furthermore, P3a was elicited only in the younger adults. In conclusion, the smaller MMN amplitude indicates that automatic processing of both frequency and temporal aspects of two-tone patterns is impaired in older adults. The failure to initiate an attention switch, suggested by the absence of P3a, indicates that impaired ASM processing of patterns may lead to less distractibility in older adults. Our results suggest age-related changes in ASM processing of patterns that cannot be explained by an inhibitory deficit.