Ego development and intelligence in a psychiatric population: Wechsler subtest scores

The relationship between Loevinger's measure of ego development and the Wechsler Intelligence Scales subtest scores was investigated in 91 adolescent and young adult psychiatric inpatients. Correlations with Verbal IQ and verbal subtests in general were positive and significant. The correlation with the Comprehension subtest was the highest and remained significant when Full Scale IQ was partialled. Post-conformists obtained the highest mean scores on Picture Arrangement; however, there was no difference among the lower stages on this subtest. The results lend support to a social reasoning component of ego development.     

Serial reconstruction of order and serial recall in verbal short-term memory

We carried out a series of experiments on verbal short-term memory for lists of words. In the first experiment, participants were tested via immediate serial recall, and word frequency and list set size were manipulated. With closed lists, the same set of items was repeatedly sampled, and with open lists, no item was presented more than once. In serial recall, effects of word frequency and set size were found. When a serial reconstruction-of-order task was used, in a second experiment, robust effects of word frequency emerged, but set size failed to show an effect. The effects of word frequency in order reconstruction were further examined in two final experiments. The data from these experiments revealed that the effects of word frequency are robust and apparently are not exclusively indicative of output processes. In light of these findings, we propose a multiple-mechanisms account in which word frequency can influence both retrieval and preretrieval processes.     

Feature and conjunction processing in the auditory modality

In five experiments, participants made speeded target/nontarget classification responses to singly presented auditory stimuli. Stimuli were defined via vocal identity and location in Experiments 1 and 2 and frequency and location in the remaining experiments. Performance was examined in two conditions inspired by visual search: In the feature condition, responses were based on the detection of unique stimulus features; in the conjunction condition, unique combinations of features were critical. Experiment 1 showed a conjunction benefit, since classifications were faster in the conjunction condition than in the feature condition. Potential confounds were eliminated in Experiments 2 and 3, which resulted in the observation of conjunction costs. In Experiments 4 and 5, we examined, respectively, whether the cost could be explained in terms of differences in interstimulus similarity and target template complexity across the main conditions. Both accounts were refuted. It seems that when the identification of particular feature combinations is necessary, conjunction processing in audition becomes an effortful process.     

Within- and between-dimensional processing in the auditory modality

Participants made speeded target-nontarget responses to singly presented auditory stimuli in 2 tasks. In within-dimension conditions, participants listened for either of 2 target features taken from the same dimension; in between-dimensions conditions, the target features were taken from different dimensions. Judgments were based on the presence or absence of either target feature. Speech sounds, defined relative to sound identity and locale, were used in Experiment 1, whereas tones, comprising pitch and locale components, were used in Experiments 2 and 3. In all cases, participants performed better when the target features were taken from the same dimension than when they were taken from different dimensions. Data suggest that the auditory and visual systems exhibit the same higher level processing constraints.     

The effects of stimulus set size and word frequency on verbal serial recall

Two experiments are reported which examine immediate serial recall for high- and low-frequency words. The words in each list were either repeatedly drawn from the same small pool of candidates (in the closed set conditions) or each word only ever occurred once during the experiment (in the open set conditions). The results consistently show an effect of word frequency but the effect of set size was only apparent for low-frequency words. It is argued that both frequency and set size effects reflect processes concerning the "clean-up" of degraded short-term memory traces.