Dr Karina J Linnell MA MSc PhD

Visual attention, visual perception, and action, all within the context of visual cognition; visual psychophysics; cognitive neuroscience of attention, including cognitive neuropsychology, fMRI imaging and ERPs.

Research interests

My research focuses on visual attention and its relation to (i) visual perception, (ii) action, (iii) consciousness and (iv) affect. In investigating these and other issues in cognition and perception, I work with normal and neuropsychological populations, and use a variety of techniques ranging from behavioural measurement (e.g., discrimination accuracy, reaction-time and movement-trajectory) through to brain imaging (fMRI and ERP).

Visual Attention and Perception

Our visual abilities seem so effortless that it is often hard to appreciate the critical role that limited-capacity attentional processing plays in vision (e.g., it seems that we only consciously perceive even the most clearly represented stimuli when we attend them). One important goal of vision and visual attention is to enable us to know what objects are where. We are currently investigating how object-based attention modulates space-based attention in support of this goal, and how the balance of space- and object-based attention changes over time and with processing load.

The role of perceptual grouping processes in object-based and feature-based attention is well documented, but we are also investigating the role of top-down attentional processing in determining perceptual grouping. All our investigations on attention and perception focus both on healthy participants and on patients with lesions in parietal and frontal cortices.

Visual Attention and Action

How do our interactions with objects in the visual scene impact on our attention to these objects? What happens when we prepare to point to, or move our eyes towards, a particular object? Is our attention allocated to the whole object, or just the part moved to? Our current findings suggest that grasping a multi-part object results in attention to the whole object, whereas pointing to it results in attention to just the relevant part or location.

We are constantly moving our eyes around the visual field, fixating first one location and then another. How does the distribution of attention change across re-fixations in a real-life task such as reading? I am currently advertising a PhD project in this area.

Visual Attention and Consciousness

The attentional blink (AB) is the name given to the phenomenon where the second of two successively presented targets fails to generate conscious awareness (or a P3 ERP component in scalp-recorded voltage fluctuations). For the AB to present itself, the second target must be presented within 250 ms of the first target, at a point in time when the first target is fully engaging attentional processes.

We have recently been awarded an ESRC project grant to use the AB phenomenon to investigate ‘Conscious awareness across time as a function of task and stimulus factors’. In this project, and in a related PhD project that I am currently advertising, we are using both behavioural and ERP measures of awareness.

Visual Attention and Affect

We are currently revisiting the question as to how anxiety affects the distribution of attention and awareness across the visual field: does it accentuate the normal attentional bias to attend to where our eyes are pointed, giving us tunnel vision, or does it diminish this bias, and focus our attention on (new) stimuli appearing in the margins of our visual field?

Selected publications