Components of the laterality effect in letter recognition: Asymmetries in iconic storage

A partial report procedure and a backward masking paradigm were employed to explore lateral asymmetries in components of letter recognition. Stimulus displays were displaced off-centre into the left visual field (LVF) or the right visual field (RVF). Visual field differences in the effect of a delayed backward mask indicated an RVF superiority in the rate of read-out or encoding. Comparison of masked and unmasked full report also yielded estimates of iconic persistence. The persistence of these peripheral displays was surprisingly brief, although it was significantly longer in the LVF (₅₇ ms) than in the RVF (₃₄ ms). Precueing by colour and by location produced a larger partial report advantage in the RVF, reflecting a superiority in selective sampling. With postcueing no partial report effect was obtained at any delay, and this failure was attributed to the briefness of the iconic persistence.     

Lateralized interference in finger tapping: comparisons of rate and variability measures under speed and consistency tapping instructions

Forty right-handed college subjects tapped with and without a verbal task under two instructional conditions (tap as quickly as possible vs. tap as consistently as possible) and two levels of verbal production (silent vs. aloud). The tapping task consisted of the alternate tapping of two keys with the index finger of the left vs. right hands, while the verbal task was anagram solution. Three rate and four variability measures of tapping performance were evaluated in the identification of lateralized interference. The results indicate that reliable lateralized interference, more right-hand than left-hand tapping disruption, was observed only for variability measures under instructions to tap as consistently as possible. Furthermore, only one of these variability measures was sensitive to an increase in lateralized interference produced by verbal production. Because of the limited demonstration of verbal laterality effects with the two-key tapping procedure in this study, conclusions suggest that the simpler manual task of repetitive tapping of one key should be viewed as the method of choice in future dual-task studies.     

The Suicidal Narrative and Its Relationship to the Suicide Crisis Syndrome and Recent Suicidal Behavior

In this study, we introduce the construct of the suicidal narrative, a hypothetical personal narrative linked to imminent suicide, and explore its relationship to near‐term suicidal risk and the suicide crisis syndrome (SCS). Psychiatric outpatients (N = 289) were administered the Columbia Suicide‐Severity Rating Scale (C‐SSRS), Suicide Crisis Inventory (SCI), and Suicide Narrative Inventory (SNI), a novel instrument combining the documented risk factors of Thwarted Belongingness, Perceived Burdensomeness, Humiliation, Social Defeat, Goal Disengagement, and Goal Reengagement. Dimensional measures of past month, lifetime, and past suicidal phenomena, incorporating ideation and behavior, were calculated from the C‐SSRS. Structural equation modeling was used to explore the interaction among variables. Factor analysis of the SNI yielded two orthogonal factors, termed Interpersonal and Goal Orientation. The former factor was comprised of Perceived Burdensomeness, Social Defeat, Humiliation, and Thwarted Belongingness, the latter of Goal Disengagement and Goal Reengagement. The Interpersonal factor correlated with both SCS severity and suicidal phenomena in each time frame and the Goal Orientation factor with no other variable. As hypothesized, the proposed model was significant for the past month only. Our findings support the construct of the suicidal narrative and its function as a near‐term suicidal risk factor.