Claire K. Naughtin

Gaze Leading: Initiating simulated joint attention influences eye movements and choice behavior

Recent research in adults has made great use of the gaze cuing paradigm to understand the behavior of the follower in joint attention episodes. We implemented a gaze leading task to investigate the initiator--the other person in these triadic interactions. In a series of gaze-contingent eye-tracking studies, we show that fixation dwell time upon and reorienting toward a face are affected by whether that individual face shifts its eyes in a congruent or an incongruent direction in response to the participants eye movement. Gaze leading also biased affective responses toward the faces and attended objects. These findings demonstrate that leading the eyes of other individuals alters how we explore and evaluate our social environment.

Make a lasting impression: The neural consequences of re-encountering people who emote inappropriately

We can learn about the affective content of the environment by observing the behavior of others; their responses to stimuli tend to be appropriate to the context. To investigate the impact of observing such appropriate, compared with inappropriate, behaviors, we developed a novel behavioral task where participants observed different faces reacting to emotional scenes. We found that affective categorization of a scene was facilitated when it was presented alongside an appropriate facial expression (Experiment 1). Further, we observed that several brain areas in the right hemisphere-the putamen, insula, orbitofrontal cortex, and dorsal anterior cingulate cortex-were more activate when viewing faces that were previously observed emoting inappropriately (Experiment 2). We contend that these areas form a network that codes for the retrieval of affective conflict information generated by observing individuals producing inappropriate emotions.

Early information processing contributions to object individuation revealed by perception of illusory figures

To isolate multiple coherent objects from their surrounds, each object must be represented as a stable perceptual entity across both time and space. Recent theoretical and empirical work has proposed that this process of object individuation is a mid-level operation that emerges around 200-300 ms after stimulus onset. However, this hypothesis is based on paradigms that have potentially obscured earlier effects. Furthermore, no study to date has directly assessed whether object individuation occurs for task-irrelevant objects. In the present study we used electroencephalography (EEG) to measure the time course of individuation, for stimuli both within and outside the focus of attention, to assess the information processing stage at which object individuation arises for both types of objects. We developed a novel paradigm involving items defined by illusory contours, which allowed us to vary the number of to-be-individuated objects while holding the physical elements of the display constant (a design characteristic not present in earlier work). As early as 100 ms after stimulus onset, event-related potentials tracked the number of objects in the attended hemifield, but not those in the unattended hemifield. By contrast, both attended and unattended objects could be individuated at a later stage. Our findings challenge recent conceptualizations of the time course of object individuation and suggest that this process arises earlier for attended than unattended items, implying that voluntary spatial attention influences the time course of this operation.

Implicit false belief tracking is preserved in late adulthood

It is now well established that relative to their younger counterparts, older adults experience difficulties on tasks that require the conscious and explicit processing of others’ mental states (e.g., beliefs, intentions; theory of mind [ToM]). Despite the importance of relatively automatic and unconscious mental state attribution processes in everyday life, no study to date has tested whether tasks that require the implicit processing of others’ belief states also show age-related changes. In this study, younger and older adults completed an implicit false belief task, in which their eye movement patterns were monitored while they passively viewed true and false belief movies. In addition, they were assessed on measures of explicit ToM processing. While older adults showed impairments in explicit ToM processing relative to younger adults, both age groups demonstrated a similar capacity for implicit false belief processing. These findings suggest that implicit components of ToM are preserved in late adulthood and are consistent with dual process models of ageing that emphasise age-related stability in automatic processing and declines in more controlled and effortful cognitive operations. We discuss the potential implications of these findings for social interactions in old age.

Decoding early and late cortical contributions to individuation of attended and unattended objects

To isolate a visual stimulus as a unique object with a specific spatial location and time of occurrence, it is necessary to first register (individuate) the stimulus as a distinct perceptual entity. Recent investigations into the neural substrates of object individuation have suggested it is subserved by a distributed neural network, but previous manipulations of individuation load have introduced extraneous visual confounds, which might have yielded ambiguous findings, particularly in early cortical areas. Furthermore, while it has been assumed that selective attention is required for object individuation, there is no definitive evidence on the brain regions recruited for attended and ignored objects. Here we addressed these issues by combining functional magnetic resonance imaging (fMRI) with a novel object-enumeration paradigm in which to-be-individuated objects were defined by illusory contours, such that the physical elements of the display remained constant across individuation conditions. Multi-voxel pattern analyses revealed that attended objects modulated patterns of activity in early visual cortex, as well as frontal and parietal brain areas, as a function of object-individuation load. These findings suggest that object individuation recruits both early and later cortical areas, consistent with theoretical accounts proposing that this operation acts at the junction of feed-forward and feedback processing stages in visual analysis. We also found dissociations between brain regions involved in individuation of attended and unattended objects, suggesting that voluntary spatial attention influences the brain regions recruited for this process.

Dynamic, continuous multitasking training leads to task-specific improvements but does not transfer across action selection tasks

The ability to perform multiple tasks concurrently is an ever-increasing requirement in our information-rich world. Despite this, multitasking typically compromises performance due to the processing limitations associated with cognitive control and decision-making. While intensive dual-task training is known to improve multitasking performance, only limited evidence suggests that training-related performance benefits can transfer to untrained tasks that share overlapping processes. In the real world, however, coordinating and selecting several responses within close temporal proximity will often occur in high-interference environments. Over the last decade, there have been notable reports that training on video action games that require dynamic multitasking in a demanding environment can lead to transfer effects on aspects of cognition such as attention and working memory. Here, we asked whether continuous and dynamic multitasking training extends benefits to tasks that are theoretically related to the trained tasks. To examine this issue, we asked a group of participants to train on a combined continuous visuomotor tracking task and a perceptual discrimination task for six sessions, while an active control group practiced the component tasks in isolation. A battery of tests measuring response selection, response inhibition, and spatial attention was administered before and immediately after training to investigate transfer. Multitasking training resulted in substantial, task-specific gains in dual-task ability, but there was no evidence that these benefits generalized to other action control tasks. The findings suggest that training on a combined visuomotor tracking and discrimination task results in task-specific benefits but provides no additional value for untrained action selection tasks.Cognition: multitasking training boosts task-specific skills onlyTraining on a dynamic multitasking game leads to task-specific improvements but this performance gain does not transfer to novel tasks. Bender and colleagues from the University of Queensland, Australia, had one group of human participants train on a combined visuomotor tracking and shape discrimination task over several days, while another group trained on the two tasks in isolation (active control group). Following training, multitasking performance selectively improved for the multitasking group and not for the active control group. Critically, this training-related benefit did not generalize to a wide range of cognitive tasks that are theoretically linked to the current dual-task paradigm, indicating that repeated exposure to two concurrent tasks induces the learning of task-specific skills so that coordination between two specific tasks can be implemented more efficiently.

Early Cortical Contributions to Object Individuation

In object individuation, spatiotemporal episodic cues are used to register an object as a distinct perceptual event, relative to other stimuli. The present study examined the time course of individuation to assess the information processing stage at which it arises and the extent to which it draws on early sensory cortices. Previous research has failed to provide definitive evidence on these issues, as individuation manipulations have co-varied with other low-level physical differences (e.g., hue, luminance). Similarly, no previous study has had both high spatial and temporal resolution, and consequently has been unable to speak directly to both the neural and cognitive substrates of individuation. Here we used a multi-modal EEG/fMRI approach and a novel enumeration paradigm that equated physical stimulus properties across conditions. We could therefore pinpoint the time window and visual sensory regions associated with individuation for items in attended and unattended locations, as indexed by set-size-dependent changes in activity. P1 (100-140 ms) and N2 (185-250 ms) event-related potentials both increased in amplitude with the number of attended targets, but unattended non-targets only modulated the N2. Using fMRI, we found that V2 and other extrastriate visual areas were the likely source of the early P1 effect observed for attended targets. Thus, object individuation appears to arise at a perceptual stage of processing and can be detected in early sensory brain regions. In addition, individuation of unattended items occurs at a later stage of processing than attended targets, suggesting a role of selective attention in this operation. Meeting abstract presented at VSS 2015.