Levels Of Perceptual Processing Research Articles

An investigation of the mechanisms underlying the link between abstract reasoning and intrusive memories: A trauma analogue study

Potentially traumatic events elicit intrusive memories to which some individuals are more vulnerable than others. Lower abstract reasoning capacity has been related to more intrusive memories. A more perceptual processing style when encoding the event may mediate this link. Another potential mechanism is lower attentional control, resulting in greater attentional bias toward trauma-related content. We examined both of these possibilities using a trauma-analogue paradigm. One hundred and twenty participants completed abstract reasoning tasks. Then, 90 participants watched a negative video, and 30 participants watched a neutral video. The level of perceptual processing (P1) and attentional bias (RT) towards trauma-related stimuli were measured with a pictorial Stroop task while recording EEG. Intrusive memories were recorded for 5 days. Abstract reasoning was not associated with intrusive memories. However, lower abstract reasoning tended to be associated with more perceptual processing (greater P1 amplitude) following the negative video. More perceptual processing also tended to be related to more intrusive memories for younger participants. A more pronounced attentional bias was related to more intrusive memories, but only for women. Unexpectedly, also for women, better verbal reasoning was linked to a more pronounced attentional bias. Results are compared to existing studies and future implications are discussed.

Effects of Healthy Aging and Gender on the Electrophysiological Correlates of Semantic Sentence Comprehension: The Development of Dutch Normative Data.

The clinical use of event-related potentials in patients with language disorders is increasingly acknowledged. For this purpose, normative data should be available. Within this context, healthy aging and gender effects on the electrophysiological correlates of semantic sentence comprehension were investigated. One hundred and ten healthy subjects (55 men and 55 women), divided among three age groups (young, middle aged, and elderly), performed a semantic sentence congruity task in the visual modality during electroencephalographic recording. The early visual complex was affected by increasing age as shown by smaller P2 amplitudes in the elderly compared to the young. Moreover, the N400 effect in the elderly was smaller than in the young and was delayed compared to latency measures in both middle-aged and young subjects. The topography of age-related amplitude changes of the N400 effect appeared to be gender specific. The late positive complex effect was increased at frontal electrode sites from middle age on, but this was not statistically significant. No gender effects were detected regarding the early P1, N1, and P2, or the late positive complex effect. Especially aging effects were found during semantic sentence comprehension, and this from the level of perceptual processing on. Normative data are now available for clinical use.

Predictive coding and the strong thesis of cognitive penetrability

In this paper, I discuss the strong thesis of cognitive penetrability (CPs), to wit, that the perceptual states (P) of a subject (S) are pervasively influenced, affected, or caused by cognitive factors (C) as expectations, memories, thoughts, goals, and so on, at all levels of perceptual processing. I argue that following the predictive coding models of perception (PC), the strong thesis of cognitive penetrability is to be expected.

Nevertheless, it persists: Dimension-based statistical learning and normalization of speech impact different levels of perceptual processing

Speech is notoriously variable, with no simple mapping from acoustics to linguistically-meaningful units like words and phonemes. Empirical research on this theoretically central issue establishes at least two classes of perceptual phenomena that accommodate acoustic variability: normalization and perceptual learning. Intriguingly, perceptual learning is supported by learning across acoustic variability, but normalization is thought to counteract acoustic variability leaving open questions about how these two phenomena might interact. Here, we examine the joint impact of normalization and perceptual learning on how acoustic dimensions map to vowel categories. As listeners categorized nonwords as setch or satch, they experienced a shift in short-term distributional regularities across the vowels' acoustic dimensions. Introduction of this ‘artificial accent’ resulted in a shift in the contribution of vowel duration in categorization. Although this dimension-based statistical learning impacted the influence of vowel duration on vowel categorization, the duration of these very same vowels nonetheless maintained a consistent influence on categorization of a subsequent consonant via duration contrast, a form of normalization. Thus, vowel duration had a duplex role consistent with normalization and perceptual learning operating on distinct levels in the processing hierarchy. We posit that whereas normalization operates across auditory dimensions, dimension-based statistical learning impacts the connection weights among auditory dimensions and phonetic categories.

Global Processing Makes People Happier Than Local Processing.

Past research demonstrates that mood can influence level of perceptual processing (global vs. local). The present research shows that level of perceptual processing can influence mood as well. In four studies, we manipulated people’s level of perceptual processing using a Navon letter task (Study 1), landscape scenery (Study 2), and Google Maps Street View images (Studies 3 and 4). Results from these studies and a meta-analysis support the conclusion that global processing results in higher happiness than local processing. In conjunction with previous findings that mood affects level of cognitive processing, these results suggest that the link between level of processing and mood may be reciprocal and bidirectional.

The levels of perceptual processing and the neural correlates of increasing subjective visibility.

According to the levels-of-processing hypothesis, transitions from unconscious to conscious perception may depend on stimulus processing level, with more gradual changes for low-level stimuli and more dichotomous changes for high-level stimuli. In an event-related fMRI study we explored this hypothesis using a visual backward masking procedure. Task requirements manipulated level of processing. Participants reported the magnitude of the target digit in the high-level task, its color in the low-level task, and rated subjective visibility of stimuli using the Perceptual Awareness Scale. Intermediate stimulus visibility was reported more frequently in the low-level task, confirming prior behavioral results. Visible targets recruited insulo-fronto-parietal regions in both tasks. Task effects were observed in visual areas, with higher activity in the low-level task across all visibility levels. Thus, the influence of level of processing on conscious perception may be mediated by attentional modulation of activity in regions representing features of consciously experienced stimuli.

Cognitive Penetration and Attention.

Zenon Pylyshyn argues that cognitively driven attentional effects do not amount to cognitive penetration of early vision because such effects occur either before or after early vision. Critics object that in fact such effects occur at all levels of perceptual processing. We argue that Pylyshyn’s claim is correct—but not for the reason he emphasizes. Even if his critics are correct that attentional effects are not external to early vision, these effects do not satisfy Pylyshyn’s requirements that the effects be direct and exhibit semantic coherence. In addition, we distinguish our defense from those found in recent work by Raftopoulos and by Firestone and Scholl, argue that attention should not be assimilated to expectation, and discuss alternative characterizations of cognitive penetrability, advocating a kind of pluralism.

The role of spatiotemporal and spectral cues in segregating short sound events: evidence from auditory Ternus display

Previous studies using auditory sequences with rapid repetition of tones revealed that spatiotemporal cues and spectral cues are important cues used to fuse or segregate sound streams. However, the perceptual grouping was partially driven by the cognitive processing of the periodicity cues of the long sequence. Here, we investigate whether perceptual groupings (spatiotemporal grouping vs. frequency grouping) could also be applicable to short auditory sequences, where auditory perceptual organization is mainly subserved by lower levels of perceptual processing. To find the answer to that question, we conducted two experiments using an auditory Ternus display. The display was composed of three speakers (A, B and C), with each speaker consecutively emitting one sound consisting of two frames (AB and BC). Experiment 1 manipulated both spatial and temporal factors. We implemented three 'within-frame intervals' (WFIs, or intervals between A and B, and between B and C), seven 'inter-frame intervals' (IFIs, or intervals between AB and BC) and two different speaker layouts (inter-distance of speakers: near or far). Experiment 2 manipulated the differentiations of frequencies between two auditory frames, in addition to the spatiotemporal cues as in Experiment 1. Listeners were required to make two alternative forced choices (2AFC) to report the perception of a given Ternus display: element motion (auditory apparent motion from sound A to B to C) or group motion (auditory apparent motion from sound 'AB' to 'BC'). The results indicate that the perceptual grouping of short auditory sequences (materialized by the perceptual decisions of the auditory Ternus display) was modulated by temporal and spectral cues, with the latter contributing more to segregating auditory events. Spatial layout plays a less role in perceptual organization. These results could be accounted for by the 'peripheral channeling' theory.

Familiarisation conditions and the mechanisms that underlie improved recognition of dysarthric speech

This investigation evaluated the familiarisation conditions required to promote subsequent and more long-term improvements in perceptual processing of dysarthric speech and examined the cognitive-perceptual processes that may underlie the experience-evoked learning response. Sixty listeners were randomly allocated to one of three experimental groups and were familiarised under the following conditions: (1) neurologically intact speech (control), (2) dysarthric speech (passive familiarisation), and (3) dysarthric speech coupled with written information (explicit familiarisation). All listeners completed an identical phrase transcription task immediately following familiarisation, and listeners familiarised with dysarthric speech also completed a follow-up phrase transcription task 7 days later. Listener transcripts were analysed for a measure of intelligibility (percent words correct), as well as error patterns at a segmental (percent syllable resemblance) and suprasegmental (lexical boundary errors) level of perceptual processing. The study found that intelligibility scores for listeners familiarised with dysarthric speech were significantly greater than those of the control group, with the greatest and most robust gains afforded by the explicit familiarisation condition. Relative perceptual gains in detecting phonetic and prosodic aspects of the signal varied dependent upon the familiarisation conditions, suggesting that passive familiarisation may recruit a different learning mechanism to that of a more explicit familiarisation experience involving supplementary written information. It appears that decisions regarding resource allocation during subsequent processing of dysarthric speech may be informed by the information afforded by the conditions of familiarisation.

See an object, hear an object file: Object correspondence transcends sensory modality

An important task of perceptual processing is to parse incoming information into distinct units and to keep track of those units over time as the same, persisting representations. Within the study of visual perception, maintaining such persisting object representations is helped by “object files”—episodic representations that store (and update) information about objects' properties and track objects over time and motion via spatiotemporal information. Although object files are typically discussed as visual, here we demonstrate that object–file correspondence can be computed across sensory modalities. An object file can be initially formed with visual input and later accessed with corresponding auditory information, suggesting that object files may be able to operate at a multimodal level of perceptual processing.

Object- and feature-based priming in visual search

Two contrasting accounts for priming in visual search have been proposed. The main difference between the two is the level of perceptual processing at which the priming effects are assumed to occur, whether priming is assumed to operate through the selective facilitation of features or at the level of selection of objects for response. The aim of the experiments here was to contrast these accounts. In the first two experiments, observers performed a search for the odd diamond in the midst of two distractor diamonds. Each diamond had two colors, but the configurations of the colors within the diamonds were different for the two experiments in ways previously shown to lend themselves differently well to object formation. The results show that priming can be both feature- and object-based, depending on the topological properties of the stimuli. This was confirmed in a third experiment, in which a quite dissimilar stimulus set was used to address the same question, once again yielding similar results. We thus show that priming operates at various levels of perceptual processing, a result consistent with new findings from neuroimaging and neuropsychology.

Blind jealousy? Romantic insecurity increases emotion-induced failures of visual perception.

Does the influence of close relationships pervade so deeply as to impact visual awareness? Results from two experiments involving heterosexual romantic couples suggest that they do. Female partners from each couple performed a rapid detection task where negative emotional distractors typically disrupt visual awareness of subsequent targets; at the same time, their male partners rated attractiveness first of landscapes, then of photos of other women. At the end of both experiments, the degree to which female partners indicated uneasiness about their male partner looking at and rating other women correlated significantly with the degree to which negative emotional distractors had disrupted their target perception during that time. This relationship was robust even when controlling for individual differences in baseline performance. Thus, emotions elicited by social contexts appear to wield power even at the level of perceptual processing.

See an object, hear an object file: Object correspondence transcends sensory modality

An important task of perceptual processing is to parse incoming information into distinct units and to keep track of those units over time as the same, persisting representations. Within the study of visual perception, maintaining such persisting object representations is helped by “object files”—episodic representations that store (and update) information about objects' properties and track objects over time and motion via spatiotemporal information. Although object files are typically discussed as visual, here we demonstrate that object–file correspondence can be computed across sensory modalities. An object file can be initially formed with visual input and later accessed with corresponding auditory information, suggesting that object files may be able to operate at a multimodal level of perceptual processing.

Change Processes in Clients' Self-Perceptions in Experiental Psychotherapy / Veränderungsprozesse in der Selbstwahrnehmung bei Klienten in der Experienziellen Psychotherapie / Procesos de cambio en la percepción que tiene el cliente de su self en psicoterapia experiencial / Les processus de changement dans les perceptions de soi chez les clients dans la psychothérapie expérientielle / Processos de mudança na auto-percepção do

This study examined the processes underlying change in self-perceptions and their relation to treatment outcome in short-term perception-focused experiential therapy. Clients (n = 20) receiving this method of therapy showed significantly greater improvement on measures of depression, self-concept, and perceptual congruence than those in a stress-management treatment control group (n = 20). Self-relevant segments, drawn from an early and later therapy session of the treatment group, were rated on the EXP-Scale and on a measure of levels of perceptual processing (LCPP-R). The analyses revealed significant early- to late-therapy improvement in depth of experiencing and ability to engage in complex, internally focused differentiating, reevaluating, and integrating kinds of mental operations. A significant relationship was also found between attained complexity in manner of processing and post-treatment reduction in depression. The implications of these findings for experiential theory and practice are discussed.

PW01-136 - Systematic parametric assessment of attentional functions based on the 'theory-of-visual-attention' II: discriminating adult ADHD-patients from healthy controls

In order to systematically specify the affected and preserved attentional components in adults with ADHD, we used an assessment tool (Finke et al, 2006) based on Bundesen's ‘theory-of-visual-attention’ (TVA) to compare two groups of adults with ADHD (medicated and unmedicated) and a matched healthy control group. TVA provides four quantitative, mathematically independent parameter estimates: visual perceptual processing speed (elements/s), working memory (WM) storage capacity (number of elements), spatial distribution of attentional weights, and top-down control. All parameters are assessed with highly similar stimuli (letters) and response requirements (verbal report), imposing comparable demands on perceptual and motor skills. Performance is assessed in terms of accuracy at certain exposure durations instead of response latency, avoiding confoundation with motor dysfunction (e.g. hyperactivity). The WM storage capacity was reduced in unmedicated ADHD patients, was significantly higher in medicated patients but was still significantly worse compared to normal controls. The spatial distribution of attentional weights is altered in that unmedicated ADHD patients did not show the normal preference for the left visual hemi-field (‘pseudoneglect'). Perceptual processing speed and top-down control of attention were comparable across groups. In conclusion, the attentional core deficit in ADHD seems to consist of a reduction in WM storage capacity, i.e. in the amount of information that can be maintained in parallel. Since no deficits in speed and top-down control have been found, slow and variable performance in response-based task might rather reflect impairments in the initiation, execution and inhibition of motor responses than impairments on the level of perceptual processing.

Object- and feature-based priming in visual search

Two contrasting accounts for priming in visual search have been proposed. The main difference between the two is the level of perceptual processing at which the priming effects are assumed to occur, whether priming is assumed to operate through the selective facilitation of features or at the level of selection of objects for response. The aim of the experiments here was to contrast these accounts. In the first two experiments, observers performed a search for the odd diamond in the midst of two distractor diamonds. Each diamond had two colors, but the configurations of the colors within the diamonds were different for the two experiments in ways previously shown to lend themselves differently well to object formation. The results show that priming can be both feature- and object-based, depending on the topological properties of the stimuli. This was confirmed in a third experiment, in which a quite dissimilar stimulus set was used to address the same question, once again yielding similar results. We thus show that priming operates at various levels of perceptual processing, a result consistent with new findings from neuroimaging and neuropsychology.

Belief in the primacy of fantasy is misleading and unnecessary

We can live in fantasy only if we survive in reality. Visual experience that carries information about the real world – that is, normal perception – serves that goal. Normal perception is not merely constrained hallucination, and it can usually be distinguished from internally generated images, with which it is rarely confused. Modulatory processes, such as attention, do indeed affect most levels of perceptual processing, but they do so without invalidating the transmission of the signals that they modulate.

The effects of lead stimulus and reflex stimulus modality on modulation of the blink reflex at very short, short, and long lead intervals.

The blink reflex is modulated if a weak lead stimulus precedes the blink-eliciting stimulus. In two experiments, we examined the effects of the sensory modality of the lead and blink-eliciting stimuli on blink modulation. Acoustic, visual, or tactile lead stimuli were followed by an acoustic (Experiment 1) or an electrotactile (Experiment 2) blink-eliciting stimulus at lead intervals of -30, 0, 30, 60, 120, 240, 360, and 4,500 msec. The inhibition of blink magnitude at the short (60- to 360-msec) lead intervals and the facilitation of blink magnitude at the long (4,500-msec) lead interval observed for each lead stimulus modality was relatively unaffected by the blink-eliciting stimulus modality. The facilitation of blink magnitude at the very short (-30- to 30-msec) lead intervals was dependent on the combination of the lead and the blink-eliciting stimulus modalities. Modality specific and nonspecific processes operate at different levels of perceptual processing.

Metric assumptions are neither necessary nor sufficient to describe similarities

Alternative models of similarity judgments that do not rest on metric space assumptions are known to be better descriptions of actual human behaviour but are ignored by Edelman. The internal spaces he postulates are a convenient fiction for artificial intelligence, but not compatible with what is now known about psychophysics at both behavioural and neurological levels of perceptual processing.

Freehand drawing impairments in probable Alzheimer's disease.

We evaluated freehand picture production of familiar objects in patients with probable Alzheimer's disease. The overall recognizability of their drawings was significantly compromised. Error analyses revealed the production of category violations and the frequent inclusion of incorrect features in a picture that were borrowed from semantically related objects, suggesting difficulty distinguishing between items with overlapping features sets in semantic memory. Analyses of individual patient drawing profiles also revealed that some patients are disproportionately compromised in expressing a particular perceptual feature, implicating difficulty at the level of perceptual processing. Regression analyses demonstrated the contribution of limited visual attentional resources. We conclude that impaired freehand drawing in probable Alzheimer's disease is multifactorial in nature.