Prawn-in-a-tube procedure: habituation or associative learning in cuttlefish?

The prawn-in-a-tube procedure (J. B. Messenger, 1973a) has been used almost exclusively to study associative learning in cuttlefish. In two experiments, the authors sought to determine whether the decline in attack responses observed in this procedure was best accounted for by habituation or associative learning. Results of Experiment 1 revealed an asymmetrical stimulus-specificity effect that could be interpreted as either an instance of habituation or of associative learning. Results of Experiment 2 demonstrated that the response decline could not be reversed following the presentation of a dishabituatory stimulus. The combined results of these experiments support the conclusion that the response decline is best viewed as a resulting of associative processes. The authors considered whether the response decline represents extinction or passive avoidance.     

Suggestibility and source monitoring errors: blame the interview style,interviewer consistency,and the child's personality

Sixty children were forced to confabulate or given misinformation about a simulated crime. Higher suggestibility in the forced confabulation group than in the suggestive group occurred even after 1 week. Interview source errors in the forced confabulation group were higher for confabulations when asked by the same person, but for control items when asked by a different person. Interview source errors in the suggestive group were higher for confabulations when asked by a different person, but for control items when asked by the same person. Confabulations were misattributed to the video by the forced confabulation more than the suggestive group. However, both groups mistakenly believed they had previously discussed control true‐event items. Suggestibility was high when imaginative and dissociative children were forced to confabulate. Control false‐event items were misattributed to the interview by compliant children and to the video by imaginative children in the forced confabulation group. Shy children in the forced confabulation group misattributed confabulations to the video, whereas distractible children in the suggestive group misattributed control false‐event items to both sources. Copyright © 2005 John Wiley & Sons, Ltd.     

Changes to the object recognition system in patients with dementia of the Alzheimer's type

Do DAT patients show category-specific deficits in object identification, and do they arise from semantic or visual damage? Participants decided whether line drawings of living and nonliving objects matched names at superordinate, basic, or subordinate levels. Patients were most impaired with superordinate decisions. Controls had most difficulty with subordinate decisions. No category-specific deficit was found with patients. Impaired superordinate decisions by the patients support semantic damage. If category-specific deficits arise from damaged semantics, they should have been found. Since they were not, and since patients performed subordinate decisions the best, a visual basis to category specificity is supported. Finally, a living advantage was found with normal observers which cannot be spurious due to differences in concept familiarity since living and nonliving objects were matched for this variable.     

Expectancy in melody: tests of children and adults

Melodic expectancies among children and adults were examined. In Experiment 1, adults, 11-year-olds, and 8-year-olds rated how well individual test tones continued fragments of melodies. In Experiment 2, 11-, 8-, and 5-year-olds sang continuations to 2-tone stimuli. Response patterns were analyzed using 2 models of melodic expectancy. Despite having fewer predictor variables, the 2-factor model (E. G. Schellenberg, 1997) equaled or surpassed the implication-realization model (E. Narmour, 1990) in predictive accuracy. Listeners of all ages expected the next tone in a melody to be proximate in pitch to the tone heard most recently. Older listeners also expected reversals of pitch direction, specifically for tones that changed direction after a disruption of proximity and for tones that formed symmetric patterns.     

Transformation defects on θ′ precipitates in Al–Cu alloys

Growth defects in the form of transformation disconnections (TDs) are considered for the precipitation of θ′ in an Al–Cu αsolid solution. The minimum sized TDs are predicted to be 1–2?nm in height, in agreement with experimental observations. One type of TD is glissile and the other (more prevalent) type is sessile, requiring climb for motion. The presence of a fault plane on one side of the sessile TD does not impede its formation. The results are in accord with symmetry theory and with the topological model for precipitation.     

Category-specific effects on the identification of non-manipulable objects

Theories of category-specific effects on visual object identification predict easier identification of non-living than living objects. The Sensory-Functional theory credits greater representational weighting of the visual properties of living objects independent of greater weighting of the functional properties of non-living objects. It predicts a lost or reversed non-living advantage for non-manipulable objects. Normal participants matched pictures of non-manipulable objects with words describing three levels of identity while visual object similarity, and concept familiarity were controlled. Consistent with the Sensory-Functional theory, living objects were matched faster than non-living objects. Concept familiarity facilitated subordinate matches. Visual similarity hampered subordinate matches and facilitated basic matches.     

Danger at the waterhole

The effects of declining accessibility of water and risk of electric shock on drinking patterns in rats were examined. Rats chose between two conditions to obtain their daily intake of water. In one condition, accessibility of water decreased systematically. In the other condition, water was readily accessible, but responses occasionally were followed by electric shock. Both variables affected drinking patterns similarly. As accessibility to water decreased, the number of drinking bouts initiated decreased but the quantity of water consumed increased. In response to risk of electric shock, the number of drinking bouts decreased but bout size increased. Results are considered in light of findings by Fanselow, Lester, and Helmstetter, (1988), Collier, Hirsch, and Hamlin (1972), and Marwine and Collier (1979).