Selective attention Flashcards
Selective attention: __
Cognitive processes that enable organisms to process relevant inputs, thoughts or actions while ignoring irrelevant or distracting ones
Selective attention is divided into:
- Voluntary: __
- Reflexive: __
Top-down, goal directed influence. Our ability to intentionally attend to something;
Bottom-up, stimulus driven. When a sensory event captures our attention
Cognitive neuroscience research on selective attention has three aims:
- Understand how attention enables and influences the
- To describe the computational processes and mechanisms that enable these effects
- To uncover how these mechanisms are __
detection, perception and
encoding of stimulus events;
implemented in the brain circuits and systems
The study of attention, neglected because of behaviourism until the 1950s, is the study of __
the constraints and limitations in how information is processed
Because attention has a capacity limitation, the system must make decisions about what __ and what __.
is selected for extended processing;
gains access to awareness
The selection, or filtering, of inputs permits high priority information to gain access
and pass processing __.
bottlenecks
The early selection bottleneck theory is the idea that:
a stimulus need not be completely perceptually analysed before it can be selected for further processing or rejected as irrelevant
The late selection bottleneck theory is the idea that:
attended and ignored inputs are processed equivalently by the perceptual system, with the bottleneck occurring at higher levels
prior to entering awareness or further attentional processing.
The Posner Cueing Task is a measure of endogenous attention because __
the orienting of attention to the cue is driven by the subject’s goals, rather than merely its physical features
In voluntary cueing studies the time taken between the presentation of the attention-directing cue and the presentation of the subsequent target varies from study to study, generally from __ to __.
100ms;
1500ms
In voluntary cueing studies, reaction times to valid trials are significantly faster than neutral or invalid, and this benefit increases with __.
cue period length
Despite attending centrally to the cue, and maintaining fixation (often checked
with eye tracking), the benefits of the valid cue are argued to result from __.
an internal shift in covert attention (a mental ‘spotlight’) to the cued visual field
Neural mechanisms underlying voluntary spatial attention have been investigated since the 70’s with __
event-related potentials (ERPs)
The P1 ERP component is seen on EEG over the occipital lobe 70-90ms after __.
a visual stimulus is presented
When a visual stimulus appears at a cued location is a Posner cueing type paradigm, the
P1 ERP is significantly larger in amplitude than when __.
the same stimulus appears at the same location but attention is focused elsewhere
The early effects of selective spatial attention on ERPs are not found when __ is based on other stimulus features, such as colour, spatial frequency, orientation, or higher order features such as object
properties (e.g., attend to chairs but ignore tables). These attentional effects will be seen in later ERPs.
attentional selection
fMRI allows you to examine how activity in visual processing areas is influenced by selective spatial attention.
In essence, sensory processing of visual stimuli is more robust when __
either covert or overt attention is applied to the stimulus
Reflexive attention is exogenous because __
the orienting of attention to the cue is driven by the low-level physical features of external stimuli and not by internal voluntary control
Reflexive attention to a location will be short-lived, stops you getting stuck at a location for too long (usually less than __)
You also get inhibition of return: __
300ms;
Recently reflexively attended locations become inhibited over time, such that responses to stimuli in those locations are slowed
Short-lived nature of reflexive attention is necessary for coping with our dynamic environment, otherwise we’d be __
constantly distracted during complex tasks such as driving a car
Voluntary, goal-directed attention involves a dorsal pathway or network, that includes the __
intraparietal cortex and superior frontal cortex
Reflexive attention, which is bottom-up, is ventral network largely lateralised to the right hemisphere and includes the __.
Specialised for detecting __, acts a circuit breaker for the dorsal stream
temproparietal cortex and inferior frontal cortex;
behaviourally relevant stimuli (salient)
Balint’s syndrome is __.
It is caused by __.
Most often diagnosed after __
a severe disturbance of visual attention and awareness;
bilateral damage to posterior parietal and occipital cortex;
stroke/CVA
In Balint’s syndrome, only one or a small subset of available objects are __.
Also mislocalised in space.
perceived at any one time
Simultagnosia: __
Difficulty perceiving the visual field as a whole scene
Ocular apraxia: __
Deficit in making eye movements to scan the visual field
Optic ataxia:__
Difficulty making visually guided hand movements
E.g., reaching for the objects the clinician is holding
In Balint’s syndrome, bilateral occipitotemporal lesions
lead to the inability to __, necessary for scene perception.
perceive multiple objects in space
Sustained attention involves __
selection, orientation and alertness
Sustained attention, or vigilance, is the least studied aspect of attention, partly due to the difficulty in __.
Even in patients with TBI, marginal deficits are found.
Generally need to engage participants on a task for __ before seeing any decrement.
identifying less than ceiling performance in healthy observers;
30mins plus
Sustained attention is defined by __.
the state of readiness to respond to rarely and unpredictably occurring signals
Sustained attention is the ability to self-sustain mindful, conscious processing of stimuli __
whose repetitive, non-arousing qualities would otherwise lead to habituation and distraction to other stimuli
Sustained attention is very much a basic attentional function that determines the efficacy of __.
selective attention
Neural network of sustained attention is thought to be a __.
Evidence to support this included:
• Increased activity of __ across the duration of a
vigilance task
• Data from the very earliest imaging studies, many using __
right fronto-parietal network;
right frontal and parietal regions;
PET
Sustained attention may be particularly compromised in TBI because TBI typically affects the __.
frontal lobes and white matter
Sustained attention: Diffuse axonal injury in TBI thought to disrupt the reticular activating system:
• White matter damage has been shown to particularly affect __
• As have frontal lobe lesions of __ hemisphere
sustained attention;
right
Sustained attention performance decrements in TBI patients is mixed. Using continuous performance measures requires the monitoring of __ and respond on detecting infrequent targets
• Such paradigms are highly vulnerable to __, where limited attention of any type is required to successfully perform the task
• Newer paradigms such as the Sustained Attention to Response Task, and Test
of Everyday Attention (Children) instead require patients to __
long sequences of stimuli;
rapid automatisation;
inhibit their ongoing behaviour in the context of a rare target
Control participants rarely make mistakes on the
SART, whereas TBI patients typically have errors
rates at __ or above, despite there being an __.
25%;
entirely predictable sequence
The inability of some TBI patients to withhold on the SART is argued to result from __.
When vigilance is poor, the __ response is
made.
the inability to maintain a sufficient level of sustained
attention to the task goal (don’t respond to 3);
automatic
The distinction between sustained attention and
inhibitory control rests on __
whether the vigilant attention for the task must be generated endogenously, rather than exogenously (e.g. the stop signal)
In TBI patients, SART failures are associated with decreased activity in __
physiological measures of arousal (e.g. SCR or electrodermal activity and alpha band activity)
In ADHD, sustained attention is routinely found to be compromised. Variation in __ to tasks is also significantly greater in ADHD.
response time
The variation in response time to tasks in ADHD is taken as an indirect measure of their inability to __.
Increased response variability is associated with decreased activity
in __.
Giving mehtylphenidate to children with ADHD increases activity in __.
Also significantly improves __.
sustain attention to task;
a right fronto-parietal network;
this right fronto-parietal network;
sustained attention (SART) and decreases response time variation.
Sustained attention in TBI is routinely found to be compromised.
Variation in __ is also significantly greater in TBI.
response time to tasks
Giving methylphenidate (MPH) to children or adults with TBI significantly improves \_\_ Trials of MPH in TBI are well supported by the available evidence, both as a \_\_, and more generally to \_\_.
sustained attention performance;
specific benefit to attention;
the cognitive complaints following TBI
