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Philip T Quinlan

Publications and source records attributed to Philip T Quinlan.

4 recordsLinked to original sources

Visual feature integration theory: past, present, and future.

Visual feature integration theory was one of the most influential theories of visual information processing in the last quarter of the 20th century. This article provides an exposition of the theory and a review of the associated data. In the past much emphasis has been placed on how the theory explains performance in various visual search tasks. The relevant literature is discussed and alternative accounts are described. Amendments to the theory are also set out. Many other issues concerning internal processes and representations implicated by the theory are reviewed. The article closes with a synopsis of what has been learned from consideration of the theory, and it is concluded that some of the issues may remain intractable unless appropriate neuroscientific investigations are carried out.

Attention↗

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.

Adult↗

Garner and congruence effects in the speeded classification of bimodal signals.

The role of attention in speeded Garner classification of concurrently presented auditory and visual signals was examined in 4 experiments. Within-trial interference (i.e., congruence effects) occurred regardless of the attentional demands of the task. Between-trials interference (i.e., Garner interference) occurred only under conditions of divided attention when making judgments about auditory signals. Of importance, the data show congruence effects in the absence of Garner interference. Such a pattern has been rarely reported in studies of the classification of purely visual stimuli and contradicts theoretical accounts asserting that the effects share a common locus. The data question the notion that Garner classification reveals fundamental insights about the nature of the perceptual processing of bimodal stimuli.

Attention↗

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.

Adult↗