Abstracts and Articles
List of Abstracts
Action matters: The role of action plans
and object affordances in selection for action
Antonella Pavese and Laurel J. Buxbaum
Moss Rehabilitation Research Institute
In a series of three experiments requiring selection of real objects for action, we investigated whether characteristics of the planned action and/or the ''affordances'' of target and distractor objects affected interference caused by distractors. In all ofthe experiments, the target object was selectedon the basis of colour and was presented alone or with a distractor object. We examined the effect of type of response (button press, grasping, or pointing), object affordances (compatibility with the acting hand, affordances for grasping or pointing), and target/distractor positions (left or right) on distractor interference (reaction time differences between trials with and without distractors). Different patterns of distractor interference were associated with different motor responses. In the button-press conditions of each experiment, distractor interference was largely determined by perceptual salience (e.g., proximity to initial visual fixation). In contrast, in tasks requiring action upon the objects in the array, distractors with handles caused greater interference than those without handles, irrespective of whether the intended action was pointing or grasping. Additionally, handled distractors were relatively more salient when their affordances for grasping were strong (handle direction compatible with the acting hand) than when affordances were weak. These data suggest that attentional highlighting of specific target and distractor features is a function of intended actions.
Pavese, A., & Buxbaum, L., (2002). Action matters: The role of action plans and object affordances in selection for action, Visual Cognition, 9(4), 559-590.
View/Download a PDF file of the full text article (496kb)
 Top of Page « Back Home
Limitations of attentional orienting:
Effects
of abrupt visual onsets and offsets on naming two objects
in a patient with bilateral posterior lesions
Antonella Pavese, H. Branch Coslett, Eleanor Saffran, and Laurel Buxbaum
Moss Rehabilitation Research Institute and Temple University
It has been proposed that the underlying deficit in simultanagnosia is the inability to
bilaterally orient attention in space due to parietal damage. In five experiments, we
examine the performance of a patient with bilateral occipito-parietal lesions, IC,
in naming pairs of line-drawings. If objects were presented simultaneously and
disappeared together (Exp. 1), IC typically named a single object. IC's performance
dramatically improved when the two drawings alternated every 500 ms (Exp. 2). This
improvement was not due to the abrupt onset of the second drawing "capturing attention",
as indicated by the results of Experiment 3. Experiment 4 and 5 demonstrated that the
crucial factor in improving IC's performance with simultaneous presentation of visual
objects was the offset of one of the two stimuli. We propose that IC's impairment in
naming two objects is attributable to the inability to "unlock" attention from the
first object detected to other objects in the array. Visual offset of the first object
presented disengages attention from the first object, allowing it to be allocated to the
second object.
Pavese, A., Coslett, B., Saffran, E., Buxbaum, L., & Lie, E. (2002) Limitations of attentional orienting: Effects of abrupt visual onsets and offsets on naming two objects in a patient with bilateral posterior lesions. Neuropsychologia, 40(7), 1097-103.
Top of Page « Back Home
Early and Late Visual Deficits in
Simultanagnosia
Antonella Pavese, Branch Coslett, Eleanor Saffran,
Laurel Buxbaum, and Eunhui Lie
Moss Rehabilitation Research Institute and Temple University
Simultanagnosia is a disorder characterized by the inability to interpret
complex visual arrays despite preserved recognition of single objects. We report
the results of a series of experiments on four patients with simultanagnosia
secondary to bilateral posterior infarcts. Anatomical and experimental data
suggest that the deficits observed in these patients can be grouped in two
different categories. Two patients showed early processing deficits as
revealed by the presence of illusory conjunctions; they also were impaired
in the binding of visual features to form objects as well as in the
allocation of attention in space. The second group of patients did not
produce illusory conjunctions but exhibited an inability in binding more
than one object feature to a location. Anatomical data collected for
clinical purposes (CT and MRI scans) revealed different patterns of brain
damage in the two groups. Patients with earlier visual deficits showed
bilateral posterior parietal/occipital lesions whereas patients with the
binding deficit showed bilateral parieto-temporal lesions. These data
suggest that simultanagnosia is a heterogeneous disorder which may be
attributable to impairments at different levels of visual processing and
have implications for accounts of normal visual processing.
Poster presented at the at the Seventh Meeting of the Cognitive
Neuroscience Society, San Francisco, April 9-11, 2000
Top of Page « Back Home
Anatomy of Word and Sentence Meaning
Michael I. Posner and Antonella Pavese
University of Oregon
Reading and listening involve complex psychological processes
that recruit many brain areas. The anatomy of processing English
words has been studied by a variety of imaging methods. While
there is widespread agreement on the general anatomical areas
involved, in comprehending words, there are still disputes about
the computations that go on in these areas. Examination of the
time relations (circuitry) among these anatomical areas can aid
in understanding their computations. In this paper we concentrate
on tasks which involve obtaining the meaning of a word in isolation
or in relation to a sentence. Our current data support a finding
in the literature that frontal semantic areas are active well
before posterior areas. We use the subject's attention to either
semantic classification or to the relation of the word to a sentence
in to amplify relevant brain areas in order to test the hypothesis
that frontal areas are concerned with lexical semantics while
posterior areas are more involved in comprehension of propositions
that involve several words.
Posner, M. I. & Pavese, A. (1998), Anatomy of Word and Sentence Meaning, Proceedings of the National Academy of Sciences, 95(3), 800-905.
View/Download a PDF file of the full text article (240kb)
Top of Page « Back Home
Pathologies of Attentional Networks
Following Traumatic Brain Injury
Antonella Pavese, Anke Heidrich, McKey Sohlberg,
Karen McLaughlin, and Michael I. Posner
University of Oregon
High-density electrical recordings were used to study the time course of processing in
tasks that mark the operation of different attention networks. We examined 16 normal
subjects and 11 individuals who had suffered traumatic brain injury (TBI) and complained
of reduced ability to concentrate. We used three tasks--Continuous Performance Task (CPT),
covert orienting task, and Stroop task--to examine vigilance, sensory orienting, and
executive control, respectively. Patients showed an overall slowing in response latencies
and reduced amplitude of late Event Related Potentials (ERPs). They also showed slower
sensory orienting and reduced hit rate in the CPT task, but no performance decrement
over time. In both CPT and covert orienting, TBI patients had similar ERP abnormalities
in processing cue information relevant for target selection. In the Stroop task,
patients showed larger interference from the irrelevant color-words and abnormal
electrical activity in midline electrodes, which in normals has been associated with
cingulate gyrus activation. These data suggest specific deficits in the executive
control network mediated by frontal areas after TBI.
Unpublished Manuscript
View/Download a PDF file of the full text article (665kb)
Top of Page « Back Home
Rehabilitation of Attentional Disorders
with Attention Process Therapy
McKey Sohlberg, Karen McLaughlin, Antonella Pavese,
Anke Heidrich, and Michael I. Posner
University of Oregon
Fourteen patients with stable acquired brain injuries exhibiting attention and
working memory deficits were given 10 weeks of attention process training (APT)
and 10 weeks of brain injury education in a cross-over design. Structured
nterviews and neuropsychological tests were used prior to rehabilitation and after
both treatments to determine the influence of the interventions on tasks of daily
life and performance on attentional networks involving vigilance, orienting and
executive function. The overall results showed that most patients made improvements.
Some of these gains were due to practice from repetitive administration of the tests.
In addition, the type of intervention also influenced the results. The brain injury
education seemed to be most effective in improving self-reports of psychosocial
function. APT influenced self-reports of cognitive function and had a stronger
influence on performance of executive attention tasks than was found with the brain
injury education therapy. Vigilance and orienting networks showed little specific
improvement due to therapy. However, vigilance level influenced the improvement
with therapy on some tests of executive attention. We consider the implications of
these results for future studies of the locus of attentional improvement and for
the design of improved interventions.
Sohlberg, M. M., McLaughlin, K., Pavese, A., & Heidrich, A., & Posner, M. I.
(2000), Rehabilitation of attention disorders with Attention Process Therapy,
Journal of Clinical and Experimental Neuropsychology, 22(5), 656-76.
View/Download a PDF file of the full text article (156kb)
Top of Page « Back Home
L'Attenzione Selettiva e il Fenomeno del Priming Negativo
[Selective Attention and Negative Priming ]
Franca Stablum and Antonella Pavese
University of Padua
Recenti teorizzazioni della psicologia cognitiva suggeriscono
che il processo di attenzione selettiva si basi su un meccanismo
di inibizione attiva dell'informazione non rilevante. Il paradigma
del priming negativo evidenzia che qualora l'informazione non
rilevante, ignorata in una prima prova, venga successivamente
ripresentata, si ottiene un significativo aumento nei tempi di
reazione associati con la risposta. Si pensa che questo fenomeno
sia attribuibile ad inibizione dell'informazione che era stata
precedentemente ignorata. Lo scopo della presente rassegna è di
esaminare le caratteristiche empiriche del fenomeno, di prendere
in considerazione i vari modelli esplica tivi proposti e di evidenziare
le implicazioni teoriche per i modelli dell'attenzione selettiva.
[Current thinking in cognitive psychology suggests that, in the
process of se lective attention, distractor information is actively
inhibited. The negative priming paradigm suggests that if a disctractor,
that has been previously ignored, is subsequently re-presented,
there is an increased reaction time associated with the response.
This is thought to be due to inhibition of di stractor information.
The aim of the present review is to examine the empi rical features
of the negative priming phenomenon and to discuss the diffe rent
models put forward to explain it.]
Stablum, F. & Pavese A. (1992),
L'attenzione selettiva e il fenomeno del priming
negativo [Selective attention and negative priming]. Giornale Italiano di
Psicologia, XIX(3), 333-356.
Top of Page « Back Home
Global/local processing and negative priming:
The influence of selection difficulty and stimulus exposure
Franca Stablum, Raffaella Ricci, Antonella Pavese, and Carlo Umiltà
University of Padua
Negative priming is a decrement in performance observed when a previously
ignored stimulus is re-presented as a target. The present study examined
the relation between selection difficulty and negative priming in five
experiments that used hierarchical stimuli (large letters made up by
small letters; Navon, 1977). The results show that negative priming is
greater when participants pay attention to the local level (more
difficult selection) than when they pay attention to the global
level (less difficult selection). However, this result is found
only when stimulus exposure of prime and probe are sufficiently
long. With shorter stimulus presentation, negative priming is still
observed, but is no longer modulated by selection difficulty. These
results suggest that both anticipatory and reactive mechanisms are
responsible for the occurrence of negative priming and that instantiation
of the reactive mechanism depends on the time available for prime and probe
election.
Stablum, F., Ricci, R., Pavese, A., & Umiltà, C., (2001).
Global/local processing and negative priming: The influence of selection difficulty and stimulus exposure,
Psychological Research/Psychologische Forschung, 65(2), 81-97.
Top of Page « Back Home
Negative priming and Stages of Selection
Antonella Pavese
University of Oregon
The negative priming effect has been associated with the process
of attentional selection in the presence of distractor information
(Neill, Valdes & Terry, 1995; Tipper & Milliken, 1995) . Performance
in selective attention tasks is affected both by perceptual discrimination
and by response compatibility between target and distractor information.
Selective attention may therefore act (a) at the level of object
selection and (b) at the level of response selection. In four
experiments using the flanker task and the colored overlapping
letter paradigm, I tested whether negative priming is affected
by manipulation of perceptual discrimination and/or response compatibility.
The results showed that: (1) perceptual discrimination between
target and distractor objects, manipulated through color similarity
and spatial distance, affects the amount of negative priming whereas
response compatibility does not; (2) negative priming increases
when target discrimination is more difficult, especially in probe
trials. These results support models of negative priming that
explain this effect in terms of maintenance of a high selectivity
state in presence of difficult target discrimination.
Pavese, A. (1997). Negative Priming and Stages of Selection:
The effect of perceptual discriminability and response congruency, Technical Report 97-05.
Eugene, OR: Institute of Cognitive and Decision Sciences.
Top of Page « Back Home
An ERP study of Location and Identity Negative Priming
Antonella Pavese
University of Oregon
Negative priming (NP) is the cost in latency and accuracy found
when an item recently presented as a distractor is re-presented
as a target. NP has been explained as a consequence of (1) inhibition
of distractor representations (Houghton & Tipper, 1994) or (2)
memory retrieval of previous episodes in which the current target
was a distractor (Neill et al., 1992). NP is found when individuals
respond to target identity as well as to its location. Identity
and location NP are often thought to have a similar underlying
mechanism, even though evidence of a dissociation between the
two effects has been found in several studies. I investigated
timing and topography of NP effects using Event Related Potentials
(ERPs) measured with high density electrode nets (Geodesic Sensor
Net). Each trial consisted of a sequence of two displays, a prime
and a probe, which included a target letter (in red) and a distractor
letter (in blue). Participants responded to the identity (Identity
task) or to the location (Location task) of the target letter.
Two conditions were analyzed: (1) the ignored repetition condition,
in which the probe target was the same letter (identity task)
or location (location task) as the prime distractor, and (2) the
control condition, in which prime and probe did not share any
letter or location. Preliminarity data suggest that timing and
topography of the difference between Ignored Repetition and Control
conditions differ depending on the task. These results are discussed
in light of the inhibition and episodic retrieval theories of
negative priming.
Poster presented at the Fifth Meeting of the Cognitive Neuroscience
Society, San Francisco, April 1998.
Top of Page « Back Home
Symbolic Distance Between Numerosity and Identity
Modulates Stroop Interference
Antonella Pavese and Carlo Umiltà
University of Padua
When two numbers are compared, the arithmetic difference between
them affects the time required for the judgment (Symbolic Distance
Effect). This study explored the effect of the symbolic distance
between stimulus dimensions in a numerical version of the Stroop
task. In four experiments, we manipulated the distance between
the enumeration response and the identity of the item to be counted.
Distractor digits that were closer to the correct enumeration
response reliably produced larger interference than distractor
digits that were farther from the enumeration response. This effect
was found with different numerosities, different enumeration processes
(counting vs. subitizing), and using distractor digits larger
and smaller than the counting response. The results suggest that
magnitude information associated with distractor digits is automatically
activated and affects the amount of Stroop interference.
Pavese, A. & Umiltà, C. (1998),
Symbolic Distance Between Numerosity and
Identity Modulates Stroop Interference, Journal of Experimental
Psychology: Human Perception and Performance, 24(5), 1535-1545.
View/Download a PDF file of the full text article (64kb)
Top of Page « Back Home
Further Evidence on the Effect of Symbolic Distance
on Stroop-like Interference in a Counting Task
Antonella Pavese and Carlo Umiltà
University of Oregon and University of Padua
Pavese and Umiltà (1998) found that, in an enumeration task,
Stroop-like interference is larger when the digit identity is
symbolically close to the enumeration response than when it is
symbolically far. In 2 experiments testing 49 undergraduates,
we further explored this phenomenon using Francolini and Egeth's
(1980) paradigm. We found that symbolic distance affected interference
even when the stimulus was briefly presented and masked. In Experiment
2, which tested numerosities outside the subitising range, individuals
used a different enumeration strategy but showed the same symbolic
distance effect. These results support the hypothesis that Stroop
interference found in enumeration tasks depends on a rapid and
automatic activation of digits' magnitude representation.
Pavese, A. & Umiltà, C. (1999),
Further Evidence on the Effect of
Symbolic Distance on Stroop-like Interference, Psychological
Research/Psychologische Forschung, 62(1), 62-71.
View/Download a PDF file of the full text article (84kb)
Top of Page « Back Home
The Influence of Affective Factors on Time Perception
Alessandro Angrilli, Paolo Cherubini, Antonella Pavese, and Sara Manfredini
University of Padua
Several studies have suggested that both affective valence and
arousal affect the perception of time. However, in previous experiments
the two affective dimensions have not been systematically controlled.
In this study, a set of emotional slides, rated for valence and
arousal (International Affective Picture System), were projected
to two groups of subjects for 2, 4 and 6 sec. One group of subjects
estimated the projection duration on an analog scale, whereas
the second group of subjects reproduced the intervals by pushing
a button. Heart rate and skin conductance responses were also
recorded during stimulus presentation as indices of attention
and arousal. Time estimation results showed neither a main effect
of valence nor of arousal. A highly significant valence by arousal
interaction affected duration judgments. For low arousal stimuli,
the duration of negative slides was judged relatively shorter
than the duration of positive slides. For high arousal stimuli,
the duration of negative slides was judged longer than the duration
of positive slides. The same interaction pattern was observed
across judgment modalities. These results are interpreted in terms
of a model of action tendency, in which the level of arousal controls
two different motivational mechanisms, one emotional and the other
attentional.
Angrilli, A., Cherubini, P., Pavese, A., & Manfredini, S. (1997),
The influence of affective factors on time perception,
Perception & Psychophysics, 59(6), 972-982.
View/Download a PDF file of the full text article (56kb)
This article was quoted by Antonio Damasio in "Remembering When" published on Scientific American in September 2002.
Top of Page « Back Home
|
