Selective attention IIII

How is selective attention related to ageing

• Our ability to select and prioritise information depends upon sensory systems, knowledge and memory capacity

• This perception and cognition changes across a life span

Selective attention and development (Enns and Brodeur, 1989)

• Investigated covert attention in observers aged 6,8 and 20 years, (in the absence of eye movement)

• Used peripheral cues

• Used short cue target onset asynchronous, the time between the cue and the target is short to maximise exogenous attention

• Cue location was predictive (80%) of target or unpredictable (random)

• They are manipulating the endogenous aspect of the cue

Correlation between selective attention and development

• Reaction time to stimuli decreased with age

• Costs associated with invalid cues decreased with age, younger participants found it harder to reorient attention from an invalid cue location

• Reaction times for adults are faster to targets at valid locations for predictable but not unpredictable cues

• Reaction time for children comparable to predictable and unpredictable cues

• Children and adults automatically orient attention towards peripheral cue (bottom up stimulus)

Selective attention and development (Konrad et al 2005)

• Used fMRI to compare brain activation in children 8-12 years and adults 20-34 years during different components of attention

• Alerting, reorienting and executive attention

Results of Konrad et al 2005

• Children showed a smaller alerting effect and don’t benefit much from a mitigating effect

• Children showed a significantly larger invalid cost

• Children showed a significantly larger interference effect

• Children are less efficient at dealing with competition associated attention

Brain regions associated with alerting in adults vs children

• Adults have a much bigger response > children

• Right cingulate gyrus

• This is the part of the brain that matures as it prepares you to make a response

Brain regions associated with reorienting in adults vs children

• Adults > children:

• Right inferior frontal gyrus

• Right temporo -parietal cortex

• Children > adults:

• Superior frontal gyrus

• Superior temporal gyrus

How are behavioural and fMRI data consistent

• Consistent with fractionation of attentional processes, you can distinguish orienting, from alerting and executive control

• Activation in response to alerting, orienting and executive attention in adults evidence top down modulation via frontoparietal attentional network

What is FPAN

• Frontoparietal attention network

• A control network

• A top down modulation of sensory input by FPAN is less established in children

What physiological changes are associated with selective attention and ageing

• Physiological changes reduce the acuity of sensory receptors eg presbycusis and presbyopia

• Ageing is associated with physiological and cognitive changes

• Physiological changes operate to reduce the acuity of your sensory receptors

What cognitive changes are associated with selective attention and ageing

• Chrystallised abilities, knowledge and vocabulary

• Fluid abilities, ability to process and solve problems eg processing speed and memory (Murman, 2015)

How does sensory acuity affect attention

• Changes in sensory acuity and cognition affect attention

• Visual search for conjunction but not feature targets decline in older observers

• Contributes to a deficit in top down prioritisation of relevant features

What is SSVEP

• Steady state visual evoked potential

• Measures top down enhancement and suppression of task relevant/irrelevant stimuli over time

• Important to equate perceptual discriminability of stimuli eg isolate the top down control