The interaction between schizotypy and latent inhibition: modulation by experimental parameters

Two recent experiments (Della Casa et al., in press) yielded the typical reduced latent inhibition (LI) in high vs low schizotypy subjects after a slow, irregularly presented masking task (Stroop task), and reduced LI in low vs high schizotypy subjects after a fast, regularly presented masking task. The present experiment was aimed at testing whether speed or regularity was responsible for the different results. The present slow, regular experiment replicated the results of the former slow, irregular experiment, i.e. reduced LI in high schizotypals and significant LI in low schizotypals, indicating that speed and not regularity is the critical experimental variable. The modulation of the schizotypy—latent inhibition relationship can be attributed to differences in attentional resources or the time available to process the to-be-target stimuli during preexposure, in accordance with the hypothesis of Lubow and Gewirtz, 1995 that automatic processing of these stimuli is critical for the development of latent inhibition in adult humans. In addition, results on Stroop and negative priming effects are presented.     

Multisensory self‐motion encoding in parietal cortex

Navigation through the environment requires the brain to process a number of incoming sensory signals, such as visual optical flow on the retina and motion information originating from the vestibular organs. In addition, tactile as well as auditory signals can help to disambiguate the continuous stream of incoming information and determining the signals resulting from one's own set of motion. In this review I will focus on the cortical processing of motion information in one subregion of the posterior parietal cortex, i.e., the ventral intraparietal area (VIP). I will review (1) electrophysiological data from single cell recordings in the awake macaque showing how self‐motion signals across different sensory modalities are represented within this area and (2) data from fMRI recordings in normal human subjects providing evidence for the existence of a functionally equivalent area of macaque area VIP in the human cortex.     

Mechanisms of aural encoding: VI. Consonants and vowels are remembered as subsets of distinctive features

An attempt was made to examine the manner in which consonants and vowels are coded in short-term memory. under identical recall conditions. Ss were presented with sequences of consonant-vowel digrams for serial recall. Sequences were composed of randomly presented consonants paired with/a/ or randomly presented vowels paired with /d/. Halle’s distinctive feature system was used to generate predictions concerning the frequency of intrusion errors. among phonemes. These predictions were based on the assumption that phonemes are discriminated in memory in terms of their component distinctive features, so that intrusions should most frequently occur between phonemes sharing similar distinctive features. The analysis of intrusion errors revealed that each consonant and vowel phoneme was coded m short-term memory by a particular combination of distinctive features which differed from one phoneme to another. A given phoneme was coded by the same set of distinctive features regardless of the number of syllables in the sequence. However, distinctive feature theories were not able to predict the frequency of intrusion errors for phonemes presented in the middle serial positions of a sequence with 100% accuracy. The results of the experiment support the notion that consonant and vowel phonemes are coded in a similar manner in STM and that this coding involves the retention of a specific set of distinctive features for each phoneme.     

A high-speed algorithm for computing conditional probabilities of substrings of sequentially observed data

An algorithm is described that computes relative frequencies of occurrence of all arbitrarily long substrings of sequential data, such as are obtained from experiments in learning/memory and verbal interaction. The algorithm offers high speed and provides systematization for the computation of empirical conditional probabilities. Use of this algorithm allows application of probabilistic and information theoretic disciplines to reveal dependencies between events separated arbitrarily in time.     

The equity restoring components of retaliation

Previous research has shown that retaliation can be an effective means of restoring equity to the relationship between a harm-doer and his victim The present study investigated the equity restoring properties of two components of retaliation the harm-doer “paying the price” for his harmful act, and the victim being given an opportunity to inflict harm Equity was restored to the relationship between the harm-doer and his victim when the harm-doer believed that his victim would be given an opportunity to inflict harm either upon the harm-doer or a neutral party When the harm-doer was led to believe that he would be retaliated against by someone other than his victim, equity restoration did not occur. The suggestion was made that the crucial factor in equity restoration may be the way in which the harm-doer thinks the relationship is viewed by his victim     

Post-retinal storage? Some further observations on Parks’ camel as seen through the eye of a needle

Parks recently reported observations with an apparatus in which successive slices of a stimulus figure could be entered on the same retinal locus. He reported that when this was done, a visual percept of the figure appeared, but one that appeared condensed in length. From this he argued that the slices, differing only in time of arrival, must be stored post-retinally and then reconstructed spatially to form the coherent figure again. In attempting to replicate this important conclusion, we found, contrary to Parks, that the appearance of the percept occurred only when the slices were spread out over the retina, and not when they were entered on the same spot. Thus, the percept is probably due to much more understandable poor temporal resolution, rather than spatial integration. Shape distortions were found corresponding to Parks’ reports, but only in the absence of any visual percepts. In spite of the failure to support all of Parks’ conclusions, the effects are seen as very intriguing ones, and may have critical theoretical ramifications.     

Dark Storm Clouds and Rays of Sunshine: Profiles of Negative and Positive Rumination About Daily Hassles and Uplifts

Daily negative events (hassles) and positive events (uplifts) have an impact on our subjective well-being, and how we react to those events (e.g., negatively ruminating by reflecting on the difficulties that come with hassles, positively ruminating by reflecting on the good aspects of uplifts) often has additional influence. However, little is known about the use of positive and negative rumination in combination. Using data from 469 adults, we examined retrospective accounts of negative and positive rumination about specific hassles and uplifts in reference to a 24-h period. Although differences in rumination were not observed across various domains (e.g., work, family, health), profiles emerged in relation to valence. Specifically, we identified four profiles of rumination: Non-Ruminators (39 %), Multivalence Ruminators (10 %), Positive Ruminators (26 %) and Negative Ruminators (24 %). Neither age nor gender systematically related to rumination profile. We further examined whether the associations among hassles, uplifts and well-being outcomes differed across these profiles. Results suggested few differences in the structural relations across the profiles, although the strength of associations was stronger for Negative Ruminators than Positive Ruminators. Results are discussed in terms of the robustness of effects of hassles and uplifts on subjective well-being across individual difference variables.