The aha effect in groups and other dynamic learning contexts.

The aha effect is a memory advantage for initially ambiguous stimuli (e.g., "The notes were sour because the seam split.

Generative learning during visual search for scene changes: enhancing free recall of individuals with and without mental retardation.

Memory for scene changes that were identified immediately (passive encoding) or following systematic and effortful search (generative encoding) was compared across groups differing in age and intelligence. In the context of flicker methodology, generative search for the changing object involved selection and rejection of multiple potential solutions prior to identification of the correct object. Such "incorrect guesses" were designed to serve as effective retrieval cues during free recall.

The self-choice effect from a multiple-cue perspective.

The self-choice effect refers to the fact that self-chosen items are remembered better than experimenter-assigned items (Takahashi, 1991). The present study investigated the hypothesis that (a) response choice involves relational processing as activation of both target and context items, and (b) such activated context items are effective as potential retrieval cues for recall of target items. In the experiment, participants chose (choice condition) or were assigned (force condition) a target to remember for each trial.

Generative processing and false memories: when there is no cost.

Encoding manipulations (e.g., levels of processing) that facilitate retention often result in greater numbers of false memories, a pattern referred to as the more is less effect (M.

Detection of changes in naturalistic scenes: comparisons of individuals with and without mental retardation.

Abilities of individuals with and without mental retardation to search for and detect salient changes to naturalistic scenes were investigated using the flicker paradigm. Located in areas of central or marginal interest, changes involved an object's color, shape, or presence. Individuals with mental retardation required more time to detect changes of all types, and the magnitude of the group difference was more pronounced for marginal-interest changes.

Guiding visual attention during acquisition of matching-to-sample.

Matching-to-sample skills are involved in language acquisition and the development of basic reading and counting abilities. The rapid, even errorless, induction of matching performances in young children and individuals with mental retardation was demonstrated here through the structuring of a visual array so as to promote detection of the relevant stimulus. Implications for theory and application are discussed.

Guided visual search in individuals with mental retardation.

The ability of individuals with mental retardation to focus on task-relevant elements of complex visual arrays and increase visual-search efficiency was investigated. Initial assessments of visual-search efficiency were conducted to identify pairs of features for the form and size dimensions for which each participant demonstrated serial search. Subsequently, color was added as a defining feature that could guide search to a subset of the elements in the array.

Stroop performance in normal control subjects: an fMRI study.

In an attempt to clarify regional signal intensity changes, which may accompany the performance of the Stroop Color-Word task, healthy subjects were imaged using the fMRI BOLD technique while performing a modified version of the task. Both the AAA and VOA subdivisions of the anterior cingulate cortex were significantly activated during the interference condition; however, only the signal intensity change within the VOA correlated with task performance. Additionally, signal intensity change was significantly increased in the VOA subdivision of the cingulate cortex when controlling for signal intensity change present during the performance of a color naming task.

Enhancing free-recall rates of individuals with mental retardation.

Generative encoding contexts promote activation of multiple retrieval routes and have been shown to enhance free-recall rates of individuals without mental retardation. The present extension to individuals with mental retardation involved a comparison of two encoding conditions: (a) fade-in, initially presenting pictures out of focus then slowly fading them into focus, and (b) fade-out, presenting pictures clearly then slowly blurring them. Results indicated that free-recall rates were greater for the fade-in items for the individuals with mental retardation and CA-matched comparisons, but not for the MA-matched group.

"Aha" effects in the generation of pictures.

An "aha" effect in memory was first reported by Auble, Franks, and Soraci (1979). They demonstrated that recall was greater for sentences that were initially incomprehensible but which were eventually comprehended, as compared with sentences that were understood from the outset. The present studies extend this "aha" effect to memory for pictorial stimuli.

Study of thrombinic activation indexes, in patients with lower limb critic ischaemia, before and after prostaglandin E1 therapy.

Background: In this study the action of a prostaglandin, PGE1, was studied in a group of patients with peripheral arterial occlusive disease (PAOD).

Methods: In 16 patients (14 men and 2 women, aged 47-70 years, mean 57 +/- 7) with PAOD, Fontaine stage IIb and III in critical ischemia, the effects on two indexes of thrombin generation and action of the endovenous administration (2 hours) of 60 micrograms of Alprostadil-PGE1 for four weeks were evaluated. In all artheriopathic patients, before and after pharmacological treatment, the following haemostatic parameters were evaluated: the prothrombin fragment 1 + 2 (F1 + 2) and the fibrinopeptide A(FPA).

Clinical and haemostatic effects of intravenous prostaglandin E1 therapy in patients with peripheral arterial occlusive disease.

Background: In this study the action of an antiaggregatory prostaglandin, PGE1, was studied in a group of patients with peripheral arterial occlusive disease (PAOD).

Methods: In 16 patients with PAOD Fontaine stage IIb and III the clinical and haemostatic effects of the endovenous administration of 60 micrograms/die of alprostadil-PGE1 for four weeks, were evaluated. Before and after pharmacological treatment, were evaluated the clinical symptoms (claudicatio intermittens and rest pain) and the following haemostatic parameters: plasma thrombomodulin (TM), beta-thromboglobulin (beta-TG), D-dimer (DD), tissue-type plasminogen activator (t-PA) and plasminogen activator-inhibitor (PAI-1).

Protein S in normal subjects and patients with peripheral arterial disease.

The aim of the present study was to investigate if alterations in protein S levels occur in peripheral arterial disease. In a group of 33 patients with peripheral arterial disease and in a group of 10 healthy volunteers we have the quantitative determination of functional protein S. The observer values show non significant difference in protein S levels among vasculopathic patients and controls (only five out of 33 patients showed low protein S levels).

Haemostatic effects of iloprost in patients with lower limb ischemia.

The aim of this study was to investigate the haemostatic effects of iloprost, a stable analogue of prostacyclin, in patients with peripheral arterial disease. In a group of 13 patients with obliterative arteriopathies of the lower limbs the plasma levels of thrombomodulin (TM), betathromboglobulin (beta-TG), D-dimer (DD) and plasminogen activator-inhibitor (pAI-1) were measured, and compared to the values obtained from 10 healthy volunteers. All the parameters were found to be significantly higher in vasculopathic patients.

Haemostatic parameters in patients with primitive venous hypertension.

In twenty patients with primitive venous hypertension and in ten healthy subjects we have determined the plasmatic levels of: Thrombomodulin (TM), beta-Thromboglobulin (beta-TG), D-Dimer (DD), the tissue activator of the plasminogen (t-PA) and the inhibitor of the activator of the plasminogen (PAI-1). The levels of the parameter we studied have shown in the patients a significant difference of beta-TG (p < 0.01) and PAI-1 (p < 0.

Haemostatic changes in patients with deep vein thrombosis.

Thrombomodulin (TM), beta-thromboglobulin (beta-TG), D-dimer (DD), tissue-type plasminogen-activator (t-PA), plasminogen activator-inhibitor (PAI-1) and quantitative determination of functional protein S (PS) were measured using ELISA procedures in the plasma of 16 untreated patients with newly-diagnosed deep vein thrombosis in the leg and in 10 healthy volunteers. No significant difference in plasma TM, t-PA and PS levels was observed among the controls and patients with deep vein thrombosis. These patients, on the other hand, showed plasma DD, beta-TG and PAI-1 levels significantly higher than the control subjects.

Hemostatic disorders associated with arterial hypertension and peripheral arterial disease.

To study a possible hypercoagulability in vascular disease, in 22 patients with essential hypertension and in 13 patients with obliterative arteriopathies of the lower limbs we measured the levels of plasma thrombomodulin (TM), plasma and urine beta-thromboglobulin (beta-TG), plasma D-dimer (DD) and plasminogen activator-inhibitor (PAI-1) and compared to the values obtained from 10 healthy volunteers. The values observed in hypertensive patients show only PAI-1 levels significantly higher. All the parameters were found to be significantly increased in vasculopathic patients.

Haemostatic variables in arterial hypertension.

In 22 untreated patients with uncomplicated essential hypertension and in 10 normotensive subjects the plasma levels of thrombomodulin (TM), beta-thromboglobulin (beta-TG), D-dimer (DD), tissue-type plasminogen activator (t-PA) and plasminogen activator-inhibitor (PAI-1) were evaluated. The observed values show no significant difference in plasma TM, plasma and urine beta-TG concentration and plasma DD among hypertensive patients and controls. On the other hand, the levels of t-PA and PAI-1 in hypertensive patients were significantly higher than the values detected in normotensive control subjects.

Incongruous item generation effects: a multiple-cue perspective.

In a series of studies, generation effects were obtained under encoding conditions designed to induce incongruous, unrelated item generation. Experiments 1 and 2, using free- and cued-recall measures, respectively, provided evidence that this unrelated generation effect was due to response-specific processing. Experiment 3 demonstrated a lack of relation between free recall and indices of clustering.

Similarities in the detection of stimulus symmetry by individuals with and without mental retardation.

Intelligence-related differences in the detection of stimulus organization previously identified by Soraci, Carlin, Deckner, and Baumeister (1990) were examined further to determine whether they would (a) extend to similar checkerboard stimuli varying solely with respect to symmetry and (b) generalize to form-like polygon stimuli. Detection performances of 10 individuals with mild mental retardation, 10 CA-matched, and 10 MA-matched individuals were assessed on a rapid presentation a two-choice match-to-sample task. The organizations of the target and distractor stimuli were varied across four levels of symmetry: double, vertical, horizontal, and asymmetrical.

Motivational orientation and span of apprehension in children with mental retardation.

Children diagnosed as mildly mentally retarded were examined with respect to performance on Estes's (1965) span-of-apprehension task. Based on their scores on the Simplified Version of the Intellectual Achievement Responsibility scale, we divided subjects into a "learned-helpless" group and a "mastery-oriented" group. Motivational orientation had a significant effect on performance, with the mastery-oriented subjects demonstrating higher detection accuracies than the learned-helpless subjects.

Span of apprehension in mentally retarded children: an initial investigation.

The present investigation is the first to apply Estes' (1965) span of apprehension task to the study of attentional functioning in mentally retarded persons. Detection accuracies of 25 children diagnosed as mildly mentally retarded and 25 non-retarded children were compared under conditions of 100-ms exposure duration, and either two, four, six or eight distractor letters. Significant main effects of subject group and distractor number were found, with no interaction.

Generalized oddity performance in preschool children: a bimodal training procedure.

Oddity performance requires relational discriminative responding, which typically is difficult to establish in children with MAs below five. In Experiment 1, a combination intrasubject reversal and multiple baseline across subjects design was used to establish the internal validity of a bimodal intervention in establishing generalized oddity performance. Six of seven children demonstrated oddity responding when presented with stimuli that instantiated the oddity relation in the visual and auditory modalities simultaneously.

Attentional functioning and relational learning.

Stimulus properties such as similarity-dissimilarity and novelty-familiarity are inherently relational and are embedded in ubiquitous stimulus contexts. Children with mental retardation and young children without mental retardation are particularly prone to failure on relational tasks such as oddity and match-to-sample (Greenfield, 1985; Soraci et al., in press).