Effects of Attention on Perception of Features and Figural Organisation

Yehoshua Tsal

doi:10.1068/p230441

Effects of Attention on Perception of Features and Figural Organisation

Perception ◽

10.1068/p230441 ◽

1994 ◽

Vol 23 (4) ◽

pp. 441-452 ◽

Cited By ~ 15

Author(s):

Yehoshua Tsal

Keyword(s):

Strong Support ◽

Dependent Measure ◽

Stimulus Location ◽

Early Selection ◽

Ambiguous Figures ◽

Directing Attention ◽

Late Selection

Four studies are reported that demonstrate effects of attention on early perceptual processes. These studies show that directing attention to stimulus location influences perceived brightness, perceived length, and the overall organisation of the Müller-Lyer figure and ambiguous figures. Since in all four studies the dependent measure was dissociated from the attentional instructions, the results are not open to traditional criticism of late-selection advocates, and therefore provide strong support for early-selection views of attention.

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Early selection, late selection, and the partitioning of structure.

The perception of structure: Essays in honor of Wendell R. Garner. ◽

10.1037/10101-010 ◽

2004 ◽

pp. 169-181

Author(s):

Donald Broadbent

Keyword(s):

Early Selection ◽

Late Selection

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The Dissociation between Early and Late Selection in Older Adults

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_00456 ◽

2013 ◽

Vol 25 (12) ◽

pp. 2189-2206 ◽

Cited By ~ 16

Author(s):

Brittany R. Alperin ◽

Anna E. Haring ◽

Tatyana Y. Zhuravleva ◽

Phillip J. Holcomb ◽

Dorene M. Rentz ◽

...

Keyword(s):

Older Adults ◽

Information Processing ◽

Test Performance ◽

Neuropsychological Test ◽

Early Selection ◽

Attention Task ◽

Age Related ◽

Different Color ◽

Task Irrelevant ◽

Late Selection

Older adults exhibit a reduced ability to ignore task-irrelevant stimuli; however, it remains to be determined where along the information processing stream the most salient age-associated changes occur. In the current study, ERPs provided an opportunity to determine whether age-related differences in processing task-irrelevant stimuli were uniform across information processing stages or disproportionately affected either early or late selection. ERPs were measured in young and old adults during a color-selective attention task in which participants responded to target letters in a specified color (attend condition) while ignoring letters in a different color (ignore condition). Old participants were matched to two groups of young participants on the basis of neuropsychological test performance: one using age-appropriate norms and the other using test scores not adjusted for age. There were no age-associated differences in the magnitude of early selection (attend–ignore), as indexed by the size of the anterior selection positivity and posterior selection negativity. During late selection, as indexed by P3b amplitude, both groups of young participants generated neural responses to target letters under the attend versus ignore conditions that were highly differentiated. In striking contrast, old participants generated a P3b to target letters with no reliable differences between conditions. Individuals who were slow to initiate early selection appeared to be less successful at executing late selection. Despite relative preservation of the operations of early selection, processing delays may lead older participants to allocate excessive resources to task-irrelevant stimuli during late selection.

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Selective Instability: Maternal Effort and the Evolution of Gene Activation and Deactivation Rates

Artificial Life ◽

10.1162/106454603322392488 ◽

2003 ◽

Vol 9 (3) ◽

pp. 317-326

Author(s):

Carlo C. Maley ◽

Stephen J. Tapscott

Keyword(s):

Gene Expression ◽

Gene Product ◽

Stochastic Systems ◽

Gene Activation ◽

Threshold Level ◽

Early Selection ◽

Autosomal Gene ◽

Activation Rates ◽

Maternal Effort ◽

Late Selection

We previously used simulations of gene expression to demonstrate that rapid activation and deactivation rates stabilized outcomes in stochastic systems. We hypothesized that transient single allele inactivation of an autosomal gene during gametogenesis or very early embryogenesis could have a selective advantage if it permits the functional sampling of each allele and precludes committing maternal effort to an embryo with a deleterious mutation. To test this hypothesis, we simulated the evolution of gene expression activation and deactivation rates and imposed two different selective pressures on the populations: (a) late selection against individuals that cannot maintain a threshold level of gene product that occurs after the investment of maternal effort (i.e., after birth); or (b) early selection: in addition to late selection, maintenance of the gene product above a threshold level was necessary for early development prior to commitment of maternal effort. We found that the opportunity to save reproductive effort from early selection caused the evolution of higher deactivation rates and lower activation rates than in the late selection condition. Thus, we predict that in the special case where early selection can save maternal investment in non-viable offspring, gene expression activation rates and deactivation rates might be selected to permit sampling of the product from each allele.

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Amyloid β-peptide and Alzheimer's disease

Essays in Biochemistry ◽

10.1042/bse0560099 ◽

2014 ◽

Vol 56 ◽

pp. 99-110 ◽

Cited By ~ 15

Author(s):

David Allsop ◽

Jennifer Mayes

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Senile Plaques ◽

Strong Support ◽

Amyloid Β ◽

Amyloid Β Peptide ◽

Amyloid Cascade Hypothesis ◽

Sequence Of Events ◽

Aβ Amyloid ◽

Amyloid Cascade

One of the hallmarks of AD (Alzheimer's disease) is the formation of senile plaques in the brain, which contain fibrils composed of Aβ (amyloid β-peptide). According to the ‘amyloid cascade’ hypothesis, the aggregation of Aβ initiates a sequence of events leading to the formation of neurofibrillary tangles, neurodegeneration, and on to the main symptom of dementia. However, emphasis has now shifted away from fibrillar forms of Aβ and towards smaller and more soluble ‘oligomers’ as the main culprit in AD. The present chapter commences with a brief introduction to the disease and its current treatment, and then focuses on the formation of Aβ from the APP (amyloid precursor protein), the genetics of early-onset AD, which has provided strong support for the amyloid cascade hypothesis, and then on the development of new drugs aimed at reducing the load of cerebral Aβ, which is still the main hope for providing a more effective treatment for AD in the future.

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Instrumental and Ideological Union Commitment: Longitudinal Assessment of Construct Validity

European Journal of Psychological Assessment ◽

10.1027//1015-5759.17.2.98 ◽

2001 ◽

Vol 17 (2) ◽

pp. 98-111 ◽

Cited By ~ 1

Author(s):

Anders Sjöberg ◽

Magnus Sverke

Keyword(s):

Construct Validity ◽

Temporal Stability ◽

Strong Support ◽

Internal Consistency Reliability ◽

Measurement Model ◽

Two Dimensions ◽

Model Parameters ◽

Longitudinal Assessment ◽

Union Commitment ◽

Union Participation

Summary: Previous research has identified instrumentality and ideology as important aspects of member attachment to labor unions. The present study evaluated the construct validity of a scale designed to reflect the two dimensions of instrumental and ideological union commitment using a sample of 1170 Swedish blue-collar union members. Longitudinal data were used to test seven propositions referring to the dimensionality, internal consistency reliability, and temporal stability of the scale as well as postulated group differences in union participation to which the scale should be sensitive. Support for the hypothesized factor structure of the scale and for adequate reliabilities of the dimensions was obtained and was also replicated 18 months later. Tests for equality of measurement model parameters and test-retest correlations indicated support for the temporal stability of the scale. In addition, the results were consistent with most of the predicted differences between groups characterized by different patterns of change/stability in union participation status. The study provides strong support for the construct validity of the scale and indicates that it can be used in future theory testing on instrumental and ideological union commitment.

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The Time Course of the Aversive Conflict Signal

Experimental Psychology (formerly Zeitschrift für Experimentelle Psychologie) ◽

10.1027/1618-3169/a000271 ◽

2015 ◽

Vol 62 (1) ◽

pp. 30-39 ◽

Cited By ~ 34

Author(s):

Julia Fritz ◽

Gesine Dreisbach

Keyword(s):

Time Course ◽

Strong Support ◽

Short Soas ◽

Priming Effects ◽

Presentation Time ◽

Psychological Evidence ◽

Study Participants ◽

Direct Investigation

The idea that conflicts are aversive signals recently has gained strong support by both physiological as well as psychological evidence. However, the time course of the aversive signal has not been subject to direct investigation. In the present study, participants had to judge the valence of neutral German words after being primed with conflict or non-conflict Stroop stimuli in three experiments with varying SOA (200 ms, 400 ms, 800 ms) and varying prime presentation time. Conflict priming effects (i.e., increased frequencies of negative judgments after conflict as compared to non-conflict primes) were found for SOAs of 200 ms and 400 ms, but absent (or even reversed) with a SOA of 800 ms. These results imply that the aversiveness of conflicts is evaluated automatically with short SOAs, but is actively counteracted with prolonged prime presentation.

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