Desrochers TM, Burk DC, Badre D, Sheinberg DL (2016). The monitoring and control of task sequences in human and non-human primates. Frontiers in Systems Neuroscience, 9.

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Abstract

Our ability to plan and execute a series of tasks leading to a desired goal requires remarkable coordination between sensory, motor, and decision-related systems. Prefrontal cortex (PFC) is thought to play a central role in this coordination, especially when actions must be assembled extemporaneously and cannot be programmed as a rote series of movements. A central component of this flexible behavior is the momentby-moment allocation of working memory and attention. The ubiquity of sequence planning in our everyday lives belies the neural complexity that supports this capacity, and little is known about how frontal cortical regions orchestrate the monitoring and control of sequential behaviors. For example, it remains unclear if and how sensory cortical areas, which provide essential driving inputs for behavior, are modulated by the frontal cortex during these tasks. Here, we review what is known about moment-tomoment monitoring as it relates to visually guided, rule-driven behaviors that change over time. We highlight recent human work that shows how the rostrolateral prefrontal cortex (RLPFC) participates in monitoring during task sequences. Neurophysiological data from monkeys suggests that monitoring may be accomplished by neurons that respond to items within the sequence and may in turn influence the tuning properties of neurons in posterior sensory areas. Understanding the interplay between proceduralized or habitual acts and supervised control of sequences is key to our understanding of sequential task execution. A crucial bridge will be the use of experimental protocols that allow for the examination of the functional homology between monkeys and humans. We illustrate how task sequences may be parceled into components and examined experimentally, thereby opening future avenues of investigation into the neural basis of sequential monitoring and control.

Gözenman F, Tanoue RT, Metoyer T, Berryhill ME (2014). Invalid retrocues can eliminate the retrocue benefit: Evidence for a hybridized account...

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Gözenman F, Tanoue RT, Metoyer T, Berryhill ME (2014). Invalid retrocues can eliminate the retrocue benefit: Evidence for a hybridized account. Journal of Experimental Psychology: Human Perception and Performance, 40(5):1748-54.
[ DOI: 10.1037/a0037474. PMCID: PMC4172509. ]

Abstract

The contents of visual working memory (VWM) are capacity limited and require frequent updating. The retrospective cueing (retro-cueing) paradigm clarifies how directing internal attention among VWM items boosts VWM performance. In this paradigm a cue appears prior to retrieval, but after encoding and maintenance. The retro-cue effect (RCE) refers to superior VWM after valid versus neutral retro-cues. Here we investigated the effect of the invalid retro-cues’ inclusion on VWM performance. We conducted 2 pairs of experiments, changing both probe type (recognition and recall) as well as presence and absence of invalid retro-cue trials. Furthermore, to fully characterize these effects over time, we used extended post-retro-cue delay durations. In the first set of experiments, probing VWM using recognition indicated that the RCE remained consistent in magnitude with or without invalid retro-cue trials. In the second set of experiments, VWM was probed with recall. Here, the RCE was eliminated when invalid retro-cues were included. This finer-grained measure of VWM fidelity showed that all items were subject to decay over time. We conclude that the invalid retro-cues impaired the protection of validly cues items, but they remain accessible, suggesting greater concordance with a prioritization account.

Janczyk M, Berryhill ME (2014). Orienting attention in visual working memory requires central capacity: Decreased retrocue effects under dualtask conditions. Attention, Perception and Psychophysics...

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Janczyk M, Berryhill ME (2014). Orienting attention in visual working memory requires central capacity: Decreased retrocue effects under dualtask conditions. Attention, Perception and Psychophysics, 76, 715-724.
[ DOI 10.3758/s134140130615x. PMCID: PMC4080723. ]

Abstract

The retro-cue effect (RCE) describes superior working memory performance for validly cued stimulus locations long after encoding has ended. Importantly, this happens with delays beyond the range of iconic memory. In general, the RCE is a stable phenomenon that emerges under varied stimulus configurations and timing parameters. We investigated its susceptibility to dual-task interference to determine the attentional requirements at the time point of cue onset and encoding. In Experiment 1, we compared single- with dualtask conditions. In Experiment 2, we borrowed from the psychological refractory period paradigm and compared conditions with high and low (dual-) task overlap. The secondary task was always binary tone discrimination requiring a manual response. Across both experiments, an RCE was found, but it was diminished in magnitude in the critical dual-task conditions. A previous study did not find evidence that sustained attention is required in the interval between cue offset and test. Our results apparently contradict these findings and point to a critical time period around cue onset and briefly thereafter during which attention is required.

Sigurdardottir HM, Michalak SM, Sheinberg DL (2014). Shape beyond recognition: Form-derived directionality and its effects on visual attention and motion perception, J Exp Psychol...

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Sigurdardottir HM, Michalak SM, Sheinberg DL (2014). Shape beyond recognition: Form-derived directionality and its effects on visual attention and motion perception, J Exp Psychol: General, 143(1), 434-454. [ DOI: 10.1037/a0032353.]

Abstract

The shape of an object restricts its movements and therefore its future location. The rules governing selective sampling of the environment likely incorporate any available data, including shape, that provide information about where important things are going to be in the near future so that the object can be located, tracked, and sampled for information. We asked people to assess in which direction several novel objects pointed or directed them. With independent groups of people, we investigated whether their attention and sense of motion were systematically biased in this direction. Our work shows that nearly any novel object has intrinsic directionality derived from its shape. This shape information is swiftly and automatically incorporated into the allocation of overt and covert visual orienting and the detection of motion, processes that themselves are inherently directional. The observed connection between form and space suggests that shape processing goes beyond recognition alone and may help explain why shape is a relevant dimension throughout the visual brain.

Reavis EA, Kohler PJ, Caplovitz GP, Wheatley TP, Tse PU (2013). Effects of attention on visual experience during monocular rivalry. Vision Research, 83(C), 76-81.

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Reavis EA, Kohler PJ, Caplovitz GP, Wheatley TP, Tse PU (2013). Effects of attention on visual experience during monocular rivalry. Vision Research, 83(C), 76-81.
[ DOI:pii: S0042-6989(13)00057-6. 10.1016/j.visres.2013.03.002. ]

Abstract

There is a long-running debate over the extent to which volitional attention can modulate the appearance of visual stimuli. Here we use monocular rivalry between afterimages to explore the effects of attention on the contents of visual experience. In three experiments, we demonstrate that attended afterimages are seen for longer periods, on average, than unattended afterimages. This occurs both when a feature of the afterimage is attended directly and when a frame surrounding the afterimage is attended. The results of these experiments show that volitional attention can dramatically influence the contents of visual experience.

Hughes HC, Caplovitz GP, Loucks R, Fendrich R (2012). Attentive and PreAttentive Processes in Change Detection and Identification. PLoS One. 7(8).e42851.

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Abstract

In studies of change blindness, observers often have the phenomenological impression that the blindness is overcome all at once, so that change detection, localization and identification apparently occur together. Three experiments are described that explore dissociations between these processes using a discrete trial procedure in which 2 visual frames are presented sequentially with no intervening inter-frame-interval. The results reveal that change detection and localization are essentially perfect under these conditions regardless of the number of elements in the display, which is consistent with the idea that change detection and localization are mediated by pre-attentive parallel processes.

In contrast, identification accuracy for an item before it changes is generally poor, and is heavily dependent on the number of items displayed. Identification accuracy after a change is substantially better, but depends on the new item's duration. This suggests that the change captures attention, which substantially enhances the likelihood of correctly identifying the new item. However, the results also reveal a limited capacity to identify unattended items. Specifically, we provide evidence that strongly suggests that, at least under these conditions, observers were able to identify two items without focused attention. Our results further suggest that spatial pre-cues that attract attention to an item before the change occurs simply ensure that the cued item is one of the two whose identity is encoded.

Monosov IE, Sheinberg DL, Thompson KG (2011). The effects of prefrontal cortex inactivation on object responses of single neurons in the inferotemporal cortex during visual search...

 J Neuroscience, 31, 15956-15961.

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Abstract

Inferotemporal cortex (IT) is believed to be directly involved in object processing and necessary for accurate and efficient object recognition. The frontal eye field (FEF) is an area in the primate prefrontal cortex that is involved in visual spatial selection and is thought to guide spatial attention and eye movements. We show that object selective responses of IT neurons and behavioral performance are affected by changes in frontal eye field activity. This was found in monkeys performing a search classification task by temporarily inactivating sub-regions of FEF while simultaneously recording the activity from single neurons in IT. The effect on object selectivity and performance was specific, occurring in a predictable spatially dependent manner and was strongest when the IT neuron’s preferred target was presented in the presence of distractors. FEF inactivation did not affect IT responses on trials in which the non-preferred target was presented in the search array.

Keywords: visual search, perception, attention, object recognition, monkey, physiology