Working-memory capacity, proactive interference, and divided attention: limits on long-term memory retrieval

Two experiments examined how individual differences in working-memory capacity (WM) relate to proactive interference (PI) susceptibility. We tested high and low WM-span participants in a PI-buildup task under single-task or dual-task ("load") conditions. In Experiment 1, a finger-tapping task was imposed during encoding and retrieval of each list; in Experiment 2, tapping was required during encoding or retrieval. In both experiments, low spans showed greater PI than did high spans under no load, but groups showed equivalent PI under divided attention. Load increased PI only for high spans, suggesting they use attention at encoding and retrieval to combat PI. In Experiment 2, only low spans showed a dual-task cost on List 1 memory, before PI built up. Results indicate a role for attentional processing, perhaps inhibitory in nature, at encoding and retrieval, and are discussed with respect to theories of WM and prefrontal cortex function.     

Author Index Volume 4

Authors Index

Author Index Volume 4     

Discontinuity of seen motion reduces the visual motion aftereffect

Would a motion-picture film of a rotating spiral induce a spiral aftereffect? This question was studied in two experiments in which Ss viewed an animated film of circles collapsing to a point. The rate of apparent motion of the collapsing circles and the discontinuity of motion—the length of jump between successively projected circles—were varied independently. A visual aftereffect like the spiral aftereffect was created. The aftereffect increased in strength and duration with the rate of motion, but at all rates of motion it declined as discontinuity of motion increased. The results are taken as evidence that motion aftereffects are caused by selective fatigue of small, directionally sensitive motion-receptive fields.     

Semantic interpretation effects on memory for faces

Five experiments investigated the effects of semantically interpreting faces on their recognition. Experiment 1 demonstrated that faces could meaningfully be related to occupational categories. In Experiments 2–5, each of a set of faces was presented with either the label of a congruent occupational category or a noncongruent label. Presenting a face with a congruent occupational label was found to enhance recognition that the face had previously been seen (Experiments 2–4), but congruent labeling also impaired the detection of distractor faces that matched previously seen faces’ categories (Experiments 3 and 4). In a forced-choice recognition test, in which distractors were highly similar to originally seen faces, congruent occupational labeling failed to increase recognition of previously seen faces (Experiment 5). These results indicate that interpreting faces, with respect to stereotyped categories, ratherthan improving a physical codein memory, led to theformation of a semantic code, which increased recognition of old items at the expense of the detection of new items. Another general finding was that faces that were rated more stereotypical were more recognizable, regardless of the accompanying label.     

Psychiatric Symptomatology and Family Functioning in Children and Adolescents with Spina Bifida

The purpose of this study was to (a) examine the occurrence of psychiatric symptomatology in children and adolescents with spina bifida, (b) investigate the relationship between psychiatric features and aspects of disability, and (c) explore the impact of spina bifida and psychiatric status on family functioning. Fifty-four children and adolescents ages 6 to 18 years (M = 12.94, SD = 3.59) were examined. Parents completed the Child Symptom Inventory (CSI) and the Family Assessment Device (FAD). Using the CSI, a psychiatric diagnostic screen, 43% of the sample obtained one, and 13% obtained two or more screening cutoff scores reflective of psychiatric diagnoses. The two most prevalent diagnostic categories were Attention-Deficit/Hyperactivity Disorder (33%) and Oppositional Defiant Disorder (13%). The sample as a whole exhibited elevated levels of clinical symptoms, with internalizing symptoms more prominent than externalizing symptoms. No differences in diagnostic categories or overall symptomatology were found based on age, gender, ambulation status, or lesion level. Overall symptom counts were positively correlated with scales on the FAD reflecting problematic family functioning (.42–.65). Results suggest that psychiatric symptomatology occurs at a high rate in children and youth with spina bifida. Although ADHD was the modal diagnostic category, the sample as a whole exhibited extensive psychiatric symptoms independent of specific diagnostic categories. Psychiatric symptoms were also associated with increased problematic functioning in families.     

Differences in the Manifest Dream Content of Anglo-American,Mexican-American,and African-American College Women

This study compares the manifest dream content of African-American college women with that of their Anglo-American and Mexican-American peers. The dream elements examined are characters, emotions, environmental press, achievement outcomes, and social interactions that are aggressive, friendly, or sexual. The results show a statistically significant difference on only one measure: environmental press. That is, the dreams of African Americans reveal a significantly stronger perception of themselves as victims of their fate rather than directors of it.     

Islam and Mental Disorders of the Older Adults: Religious Text,Belief System and Caregiving Practices

Journal of Religion and Health - This paper illustrates the impact of Islamic religious texts on dementia care in the Middle East. It examines how old age and older adults mental disorders are...     

Reperfusion of Specific Brain Regions by Raising Blood Pressure Restores Selective Language Functions in Subacute Stroke

We report a series of six single subject studies examining the effects of pharmacological blood pressure elevation on regional brain perfusion and language function. Previous reports indicate that hypoperfusion of specific brain regions, as delineated by magnetic resonance perfusion weighted imaging (PWI), is associated with disruption of selective lexical functions. On this basis, we hypothesized that reperfusion of the same regions, in the absence of infarct in that region, would restore the associated lexical function. We present five patients with impaired lexical-semantics associated with poor perfusion, but not infarction, of Brodmann's area 22 (BA 22), and one patient with impaired lexical-semantics and a superimposed deficit in retrieving the phonological representations of words, associated with poor perfusion Brodmann's area 37 (BA 37) as well as BA 22. Each patient was treated with induced blood pressure elevation to increase perfusion of the ischemic and dysfunctional tissue. Daily testing of naming and comprehension, with stimulus sets matched for frequency, familiarity, and length, showed improved lexical-semantics in the patients who showed reperfusion of BA 22 and improved oral naming (but not lexical-semantics) in the patient who showed reperfusion of BA 37. These cases illustrate that loss of function with hypoperfusion of a circumscribed area of the brain, and recovery of the same function with improved perfusion of that brain region, can reveal brain/language relationships prior to reorganization after brain injury.     

A controlled-attention view of working-memory capacity.

In 2 experiments the authors examined whether individual differences in working-memory (WM) capacity are related to attentional control. Experiment 1 tested high- and low-WM-span (high-span and low-span) participants in a prosaccade task, in which a visual cue appeared in the same location as a subsequent to-be-identified target letter, and in an antisaccade task, in which a target appeared opposite the cued location. Span groups identified targets equally well in the prosaccade task, reflecting equivalence in automatic orienting. However, low-span participants were slower and less accurate than high-span participants in the antisaccade task, reflecting differences in attentional control. Experiment 2 measured eye movements across a long antisaccade session. Low-span participants made slower and more erroneous saccades than did high-span participants. In both experiments, low-span participants performed poorly when task switching from antisaccade to prosaccade blocks. The findings support a controlled-attention view of WM capacity.