A Rapid and Precise On-Response in Posterior Parietal Cortex

Bisley, James W.; Krishna, B. Suresh; Goldberg, Michael E.

doi:10.1523/jneurosci.5007-03.2004

Cited by 129 publications

(104 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Consistent with previous research (Bisley et al, 2004), the LIP population responses for both Target-In and Target-Out trials exhibited a very short latency of 47.5 ms. More importantly, both SUA and MUA discriminated between Target-In and Target-Out trials as early as 52.5 ms after stimulus onset (t test on the average SUA and MUA separately, p Ͻ 0.05), in line with the 50 ms selectivity latency of the fastest LIP neurons recorded by Buschman and Miller (2007). Our short population latencies were confirmed by calculations of the neural selectivity latencies (Target-In versus Target-Out) of individual recording sites (t tests on 20 ms bins): the fastest LIP neurons (fifth percentile) showed selectivity latencies of 50 ms [median selectivity latency: 150 ms].…”

Section: Multiple-distractor Tasksupporting

confidence: 90%

Functional Heterogeneity of Macaque Lateral Intraparietal Neurons

Premereur¹,

Vanduffel²,

Janssen³

2011

J. Neurosci.

View full text Add to dashboard Cite

The macaque lateral intraparietal area (LIP) has been implicated in many cognitive processes, ranging from saccade planning and spatial attention to timing and categorization. Importantly, different research groups have used different criteria for including LIP neurons in their studies. While some research groups have selected LIP neurons based on the presence of memory-delay activity, other research groups have used other criteria such as visual, presaccadic, and/or memory activity. We recorded from LIP neurons that were selected based on spatially selective saccadic activity but regardless of memory-delay activity in macaque monkeys. To test anticipatory climbing activity, we used a delayed visually guided saccade task with a unimodal schedule of go-times, for which the conditional probability that the go-signal will occur rises monotonically as a function of time. A subpopulation of LIP neurons showed anticipatory activity that mimicked the subjective hazard rate of the go-signal when the animal was planning a saccade toward the receptive field. A large subgroup of LIP neurons, however, did not modulate their firing rates according to the subjective hazard function. These non-anticipatory neurons were strongly influenced by salient visual stimuli appearing in their receptive field, but less so by the direction of the impending saccade. Thus, LIP contains a heterogeneous population of neurons related to saccade planning or visual salience, and these neurons are spatially intermixed. Our results suggest that between-study differences in neuronal selection may have contributed significantly to the findings of different research groups with respect to the functional role of area LIP.

show abstract

Section: Multiple-distractor Tasksupporting

confidence: 90%

Functional Heterogeneity of Macaque Lateral Intraparietal Neurons

Premereur¹,

Vanduffel²,

Janssen³

2011

J. Neurosci.

View full text Add to dashboard Cite

show abstract

“…Interestingly, the LIP exhibits neuronal latencies to visual stimulation that are only slightly longer than in primary and secondary visual cortex and much shorter than in inferior temporal cortex, suggesting that it has privileged access to feedforward information (Bullier, 2001;Gottlieb et al, 1998). Thus, LIP shows a rapid on-response to any visual stimulus irrespective of its current relevance, followed by a later sustained activity which is sensitive to attentional modulations (Bisley et al, 2004). This pattern of response is reminiscent of the sequence of processing stages identified in our study.…”

Section: Discussionsupporting

confidence: 69%

Task relevance effects in electrophysiological brain activity: Early, but not first

2014

View full text Add to dashboard Cite

A current controversy surrounds the question whether high-level features of a stimulus such as its relevance to the current task may affect early attentional processes. According to one view abruptly appearing stimuli gain priority during an initial feedforward processing stage and therefore capture attention even if they are irrelevant to the task. Alternatively, only stimuli that share a relevant property with the target may capture attention of the observer. Here, we used high-density EEG to test whether task relevance may modulate early feedforward brain activity, or whether it only becomes effective once the physical characteristics of the stimulus have been processed. We manipulated task relevance and visual saliency of distracters presented left or right of an upcoming central target. We found that only the relevance of distracters had an effect on manual reaction times to the target. However, the analysis of electrocortical activity revealed three discrete processing stages during which pure effects of distracter saliency (~80-160 ms), followed by an interaction between saliency and relevance (~130-240 ms) and finally pure effects of relevance (~230-370 ms) were observed. Electrical sources of early saliency effects and later relevance effects were localized in the posterior parietal cortex, predominantly over the right hemisphere. These findings support the view that during the initial feedforward stage only physical (bottom-up) factors determine cortical responses to visual stimuli, while top-down effects interfere at later processing stages.

show abstract

“…Recently it has been shown that the LIP area contains three signals (33-36): a bottom-up stimulus-onset signal, a saccade-related signal, and a cognitive, top-down signal that distinguishes targets from distractors. Interestingly, these different types of signals arrive at different latencies: The cognitive signal has latencies of about 117-133 ms, which is similar to our estimated delay for value processing (∼184 ms), but the visual signal is much faster, at ∼40 ms (33,34). In summary, the LIP area likely contains a priority map that integrates bottom-up and top-down information to guide visuospatial attention and eye movements (37,38).…”

Section: Discussionsupporting

confidence: 66%

Dynamic integration of information about salience and value for saccadic eye movements

Schütz

Trommershäuser

Gegenfurtner

2012

Proc. Natl. Acad. Sci. U.S.A.

134

117

View full text Add to dashboard Cite

Humans shift their gaze to a new location several times per second. It is still unclear what determines where they look next. Fixation behavior is influenced by the low-level salience of the visual stimulus, such as luminance, contrast, and color, but also by highlevel task demands and prior knowledge. Under natural conditions, different sources of information might conflict with each other and have to be combined. In our paradigm, we trade off visual salience against expected value. We show that both salience and value information influence the saccadic end point within an object, but with different time courses. The relative weights of salience and value are not constant but vary from eye movement to eye movement, depending critically on the availability of the value information at the time when the saccade is programmed. Shortlatency saccades are determined mainly by salience, but value information is taken into account for long-latency saccades. We present a model that describes these data by dynamically weighting and integrating detailed topographic maps of visual salience and value. These results support the notion of independent neural pathways for the processing of visual information and value.neuroeconomics | decision-making | cue combination | visual perception B ecause of foveal specialization for high acuity and color vision, humans frequently move their eyes to project different parts of the visual scene on the fovea. Although the basic networks for the programming and execution of saccades have been studied for decades (1, 2), surprisingly little is known about the neural processes that underlie selection of the point of fixation of the next saccade. To some degree, the weighted combination of basic visual-stimulus features can predict saccadic eye movements in natural scenes (3-5). These basic stimulus features are, among others, local differences in luminance, color, or orientation and are combined by the visual system in a bottom-up image-based salience map. However, the salience difference between fixated and nonfixated image locations is typically rather small (6, 7), indicating that the influence of salience may be modulated by other factors. Visual salience, by definition, is determined by features of the visual scene alone and therefore is determined exclusively by visual bottom-up processing. Other factors reflect the influence of top-down processing. Task demands, for example, exhibit constraints on gaze patterns in different activities such as visual searching (8), manipulating an object (9), playing ball sports, preparing a cup of tea (10), and navigating between obstacles (11). In all these examples, gaze is concentrated on objects that are relevant for the task.Along different lines, recent research in neuroeconomics has used saccadic eye movements as a tool to uncover the neural bases of primate choice behavior. The results of these experiments indicate that value can be an important determinant of the neural activity underlying the selection of a saccadic target when one object bear...

show abstract

A Rapid and Precise On-Response in Posterior Parietal Cortex

Cited by 129 publications

References 27 publications

Functional Heterogeneity of Macaque Lateral Intraparietal Neurons

Functional Heterogeneity of Macaque Lateral Intraparietal Neurons

Task relevance effects in electrophysiological brain activity: Early, but not first

Dynamic integration of information about salience and value for saccadic eye movements

Contact Info

Product

Resources

About