The effect of similarity between elemental stimuli and compounds in olfactory patterning discriminations

We studied the ability of honeybees to discriminate between single odorants and binary olfactory mixtures. We analyzed the effect of the number of common elements between these two stimulus classes on olfactory discrimination. We used olfactory conditioning of the honeybees' proboscis extension reflex (PER), a paradigm in which odors can be associated with a reinforcement of sucrose solution. Bees were asked to discriminate reinforced from nonreinforced olfactory stimuli. They were trained with two elemental odors (A and B) versus a binary olfactory mixture. The mixture was either AB (group 2CE, two common elements), AC (group 1CE, one common element A), or CD (group 0CE, no common element). Three groups followed a positive patterning schedule (mixture reinforced and elements nonreinforced: groups 2CE+, 1CE+, and 0CE+) and three other groups a negative patterning schedule (mixture nonreinforced and elements reinforced: groups 2CE-, 1CE-, and 0CE-). We showed that a reduction of similarity (number of common elements) between elemental odors and compounds enhanced the ability to discriminate elements from compounds and that the kind of compound processing used by the bees supports theories that assume nonelemental compound processing (i.e., that exclude the mere summation of the elemental associative strengths upon compound presentation).     

Who is exaggerating cognitive impairment and who is not?

This chart review examined the effects of effort on neuropsychological assessment and test performance patterns among genuine and exaggerating patients, with and without neurological findings, as aids to diagnosing symptom exaggeration. The sample consisted of 561 consecutive patients involved in compensation claims. With a flexible neuropsychological test (NPT) battery, the claims were assessed over 2 days. The sample included 303 patients evaluated for traumatic brain injury, 55 patients with neurological disease, and 203 patients assessed for other conditions (eg, depression or chronic pain). An average of 38 ability measures per patient were used to generate an overall NPT domain score. Composite scores were also computed for symptom validity tests, self-report measures of psychiatric symptoms, and memory complaint inventory. Seven NPT cognitive subdomain scores were multiply regressed onto the symptom validity test composite, accounting for 45% of its total variance. Patients were also assigned to Genuine or Exaggerator groups based on symptom validity test performance. The NPT for Exaggerating patients averaged 1.43 standard deviations below that of Genuine patients, suggesting that NPT scores for most Exaggerating patients are underestimates of their true ability. Factor analysis results differed between these groups. As a result, clinicians might avoid falsely identifying genuine patients as exaggerating by incorporating their self-reports of psychiatric symptoms and memory complaints into the diagnostic process.     

Activation of Syntactic Information During Language Production

In order to produce utterances, people must draw upon syntactic information. This paper considers how evidence from syntactic priming experiments casts light upon the nature of syntactic information activation during language production. We examine three issues: the way in which syntactic information is initially activated, the circumstances under which activation may persist or dissipate, and the effects of residual activation of syntactic information on subsequent language production. Evidence from dialog experiments suggests that the information that is initially activated is the same in both production and comprehension. Evidence about the persistence of activation following initial activation is more complex. We suggest that persistence may be related to the potential relevance of the information for subsequent syntactic processing. We show that current evidence is inconclusive about how long syntactic information remains activated.     

Commentary: A Patient's Perspective on Predictive Testing for Alzheimer Disease

Commentary

Commentary: A Patient's Perspective on Predictive Testing for Alzheimer Disease     

Joyce's Argument with Himself/Or, Reading Joyce's Inside Narrative

James Joyce's argument with himself about where he should practice his art and with what literary tradition he should identify—Irish, British, or European—is represented by several of the characters and episodes in his short story The Dead.In the main character, Gabriel Conroy, Joyce represented the conflicts that he himself experienced. But in many of the minor characters Joyce also reflected parts of his own wishes and fears.In this story, Joyce rejects the possibilities of artistic identification with Ireland and England, and, in the dynamics of the tale, arrives at the understanding that to fulfill his artistic aspirations, he must make an identification with the great European tradition, and also live in Europe; if he stays in Ireland or attempts to be an English author, he will be, as he portrays Gabriel to be, paralyzed, imitative, and a failure as an artist. Joyce himself took the decisive path that Gabriel could not choose.     

Group collaboration in recognition memory

Group collaboration was examined in item and associative recognition. The present study distinguishes between group effects versus collaborative processes and defines the latter as interactive information exchange among group members. By that definition, many group effects do not involve collaboration. For example, group performance can exceed individual performance by pooling the increased resources of the group. Specifically, a group advantage can be obtained by deferring to a majority vote or to the group's best member. For both item and associative recognition, a group advantage was obtained that could not be accounted for by resource pooling. Collaborative facilitation was shown reliably in recognizing targets but not for rejecting distractors.     

Thought suppression and its effects on thought frequency, appraisal and mood state in individuals with obsessive-compulsive disorder

Leading models of obsessive-compulsive disorder (OCD) implicate thought suppression as a key factor in the escalation and persistence of the disorder. This experiment examined the effects of suppression on the frequency of obsessional thoughts in 50 individuals with a primary diagnosis of OCD, and also investigated the effects of participants' appraisals regarding their failures in thought control on distress about intrusive thoughts and on mood. Participants' most upsetting obsessional thought was primed and they then monitored its occurrence over two 4-min intervals. In the first interval, half of the participants were instructed to suppress their obsessional thought and half were instructed not to suppress any thoughts. In the second interval, all participants were given the 'Do Not Suppress' instructions. Participants rated their suppression effort and discomfort over thought occurrences after each interval and recorded their appraisals of thought recurrences during the first interval. Mood state was then reassessed. No ironic effect of suppression on frequency was noted. However, negative appraisals of thought recurrences were associated with more discomfort over thought occurrences and more negative mood at Time 2. These findings suggest that interpretations regarding failures in thought control may be of central importance in understanding obsessional problems.     

Mapping the MMPI-2 Restructured Clinical scales onto normal personality traits: evidence of construct validity

The MMPI-2 Restructured Clinical (RC; Tellegen et al., 2003) scales were developed to remove common factor variance that saturates the clinical scales and create a more distinct set of measures, yielding a new set of scales with improved convergent and discriminant validity. In this study, we examined the relation between RC scale scores and scores on the Multidimensional Personality Questionnaire (MPQ; Tellegen, in press), a measure of normal personality, using a sample of 811 college students. The results indicate strong convergence between the RC scales and expected MPQ higher order factors and primary scales. The RC scales also demonstrated expected improved convergent and discriminant validity over the clinical scales.