Attention

What is Attention?

 

  • Definition: Attention is often described as the ability to focus on certain stimuli while ignoring others. It can be hard to define but is essential for processing the vast amount of information we receive through our senses.

 

  • Types of Attention:

    • Selective Attention: Focusing on one piece of information while ignoring others.

    • Sustained Attention: The ability to maintain focus over time (vigilance).

    • Divided Attention: The ability to multitask, shifting focus between multiple stimuli.

    • Overt Attention: Focusing on what you are looking at directly.

    • Covert Attention: Focusing on something without directly looking at it.

Importance of Attention:

 

  • Attention is critical because we receive too much input to process everything at once. This leads to the concept of attention as a limited capacity resource.

  • Failures of attention can lead to negative outcomes in daily life, such as:

    • Educational challenges (distractions, underachievement).

    • Workplace inefficiencies.

    • Accidents (e.g., distracted driving).

    • Clinical disorders (e.g., ADHD, anxiety, schizophrenia).

Processing Limitations:

 

  • Attention acts as a bottleneck in the processing of sensory information. Questions that arise from this include:

    • How much does the brain process things we aren’t directly paying attention to?

    • What determines which stimuli we pay attention to?

    • How does attention relate to cognitive control?

 

 

 

 

Studying Attention:

 

1.    Eye Movements:

o   Visual attention is often studied by tracking where people fixate. For example, in a crowded scene, eye movements can show what captures attention.

o   Example: A diagram in the slides shows eye movement paths on a sports scene, indicating focus on the game versus the surroundings.

 

2.    Reaction Time (RT) Experiments:

o   These experiments assume that moving attention takes time, and reaction times can be measured to determine attention shifts.

o   Spatial Cuing Task:

§  Valid Cue: A cue that correctly predicts the location of the target leads to faster response times.

§  Invalid Cue: When a cue misleads, response times are slower, indicating the movement of attention to a non-target location.

 

3.    Visual Search Tasks:

o   Pop-out Search: A target that visually “pops out” (e.g., a green "O" among red "X"s) leads to quick detection, unaffected by the number of distractors.

o   Conjunction Search: When the target is defined by a combination of features, the search becomes slower as the number of distractors increases, requiring a serial search.

Distractor Effects:

 

  • Stroop Task: A well-known experiment where participants are asked to name the ink colour of words. When the word meaning conflicts with the ink colour (e.g., the word "RED" printed in blue), response times slow down, showing that we can’t completely ignore irrelevant information.

 

  • Flanker Task: Participants must identify a central target while ignoring surrounding distractors. When the distractors are incongruent (e.g., surrounding letters are different from the target), response times increase.

 

 

Attentional Capture:

 

  • Singleton Attentional Capture Task: When a non-target (distractor) is highly salient (e.g., a different colour), it captures attention and increases reaction times. If the salient item is the target, it reduces reaction time, providing evidence for attentional capture.

Self-Report and Error Measures:

 

  • These methods are used to assess subjective experiences of attention, such as mind-wandering and distraction.

 

  • Change Blindness: An example of how we might fail to notice changes in a visual scene, revealing the limitations of attention.

 

  • Mind-Wandering: Self-report measures show that people who frequently report mind-wandering also perform worse on tasks requiring sustained attention.

Neural Mechanisms of Attention:

 

  • Neuroimaging Studies:

    • Certain brain areas are selectively involved in processing specific stimuli. For instance:

      • Fusiform Face Area (FFA): Responds to faces.

      • Parahippocampal Place Area (PPA): Responds to places or scenes.

    • Covertly attending to faces increases activity in the FFA, even without direct gaze, while attending to places increases activity in the PPA.

 

 

 

 

 

 

Early Selection

 

  • Broadbent's Filter Theory (1958):

    • Filtering occurs before stimuli are analysed for meaning. Only the attended message is processed for meaning, while ignored stimuli are filtered based on physical characteristics.

    • Components:

1.    Sensory Store: Temporarily holds information.

2.    Filter: Analyses based on physical traits (e.g., voice tone).

3.    Detector: Analyses meaning for attended stimuli.

4.    Short-term Memory: Holds processed information.

Problems with Early Selection

 

  • Evidence Against:

    • Moray (1959): People notice their own names in the ignored stream. There is a ‘breakthrough.’

    • Treisman (1960): Bilingual participants process ignored information if it's in their second language.

    • Gray & Weddeburn (1960): People combine attended and unattended information (e.g., “Dear Aunt Jane” instead of “Dear 7 Jane”).

Treisman’s Attenuation Model

 

  • Modification of Filter Theory: Instead of being completely filtered, unattended stimuli are attenuated (weakened).

    • Words have a threshold of signal strength needed for detection.

    • Personal or contextually primed words have lower thresholds, explaining why one’s name can "breakthrough" the filter.

Late Selection

 

  • Theory by Deutsch & Deutsch (1963), Kahneman (1973), Duncan (1980):

    • All stimuli, including ignored inputs, are processed for meaning before selection occurs.

    • Supporting Evidence:

      • MacKay (1973): Unattended words influenced the interpretation of ambiguous sentences.

      • Eriksen & Eriksen (1974): Distractor interference (slower response times) shows both streams of information are processed.

The Cocktail Party Effect (Colin Cherry, 1953)

 

  • Demonstrates selective attention, where a person can focus on one conversation amidst background noise.

  • Dichotic Listening Task:

    • Participants shadowed one ear's message while ignoring the other.

    • Findings showed that physical characteristics of the ignored stream were processed, but not the content or meaning.

 

Load Theory (Lavie)

 

  • Combination of Early and Late Selection:

    • Both types of selection are possible, depending on perceptual load.

    • High Load: Perceptual capacity is fully occupied, leading to early selection (filtering of distractors).

    • Low Load: Spare capacity allows for processing distractors, resulting in late selection.

 

  • Supporting Evidence:

    • Inattentional Blindness: Studies like "Gorillas in our midst" (Simons & Chabris, 1999) show that when attention is focused, people miss unexpected stimuli.

    • Neuroimaging (Schwartz et al., 2005): High perceptual load reduces background processing in the visual cortex.

    • Amygdala Activity (Bishop et al., 2007): Reduced response to emotional stimuli (e.g., fearful faces) under high load.

Implications for Individual Differences

 

  • Perceptual Capacity Varies:

    • Individuals with lower perceptual capacity (e.g., children, older adults, individuals with autism) may need higher loads to avoid distraction.

    • Video Games: Players with video game experience show less distraction under high loads, indicating increased perceptual capacity.

Summary of Theories

 

1.    Early Selection: Filters irrelevant information before it reaches the stage of meaning analysis.

2.    Late Selection: All information is processed for meaning, and selection happens later.

3.    Load Theory: The stage of selection depends on the task's perceptual load, allowing both early and late selection under different conditions.

Key Concepts in Attention:

 

  • Top-Down Goals:

    • Attention guided by internal goals (e.g., searching for a friend in a crowd).

    • Even though top-down goals influence attention, they don't fully control it.

  • Bottom-Up Stimulus Characteristics:

    • Attention influenced by external stimuli with notable physical properties (e.g., bright signs, moving objects).

    • Stimuli can capture our attention involuntarily due to their salience.

 

Vocabulary:

 

  • Bottom-Up (Stimulus-Driven): Exogenous, involuntary, reflexive.

  • Top-Down (Goal-Driven): Endogenous, voluntary, executive attention, attentional control.

 

Biased Competition Theory (Desimone & Duncan, 1995):

 

  • Attention is a competition between stimuli for neural representation.

  • This theory integrates both top-down and bottom-up processes, although debates exist regarding their respective influences.

 

Stimulus-Driven Attentional Capture:

 

  • High-Salience Stimuli: Objects that stand out due to colour, movement, or relevance to us are more likely to capture attention.

 

  • Singleton Attentional Capture Task (Theeuwes, 1992):

    • Test whether attention can be exclusively top-down.

    • Result: Even when focusing on shapes, irrelevant but salient colours increased response times (RTs), indicating the failure of top-down selectivity.

 

Theeuwes' Model:

 

  • Attention selection happens in two stages:

1.    Initial Sweep: Entirely bottom-up. Focuses on the most salient item in the visual field.

2.    Evaluation: Determines whether the selected item is relevant or not.

  • Attentional Window: Attention is captured only within the scope of this window, defined by spatial cues.

 

Contingent Capture (Folk & Remington, 1992):

 

  • Attention is task-contingent:

    • E.g., a yellow sign may capture attention because you are looking for a yellow taxi, not because of its salience alone.

  • Experiment: When the target and cue shared similar features (e.g., colour or onset), attentional capture occurred. If they didn't, capture was reduced, suggesting attention is dependent on task settings.

 

Top-Down vs Bottom-Up Debate:

 

  • Top-Down Advocates: Argue that only relevant stimuli, defined by goals, capture attention.

  • Bottom-Up Advocates: Emphasize the automatic capture of attention by salient stimuli.

 

Meaning and Personal Relevance in Attentional Capture:

  • Examples:

 

  • Threat: Stimuli representing danger (e.g., a spider for someone with arachnophobia) are more likely to capture attention.

  • Familiarity/Expertise: Experts in a field (e.g., football or music) may be quicker to notice related stimuli.

  • Value and Selection History: Stimuli associated with reward or personal relevance tend to attract attention more effectively.

 

Summary of Attentional Determinants:

 

1.    Top-Down Goals: Attention is directed by what we seek or expect.

2.    Bottom-Up Properties: Attention is captured by the physical characteristics of stimuli.

3.    Value/Selection History: Previous experiences, rewards, and personal relevance can shape what captures attention.

 

 

 

 

(4) Overview of Attention and Distraction

 

  • Internal vs. External Distraction:

 

  • Traditional attention research has primarily focused on external sources of distraction, such as loud noises or visual disturbances.

  • In daily life, distraction often comes from internal sources, such as mind-wandering (e.g., thinking about unrelated tasks like "Shall I get a burrito after this?").

 

Perceptual Load and Distraction

 

  • Perceptual Load Theory:

    • Higher perceptual load (more demanding tasks) reduces the likelihood of external distractions.

    • Forster & Lavie (2009) explored whether this theory also applied to mind-wandering, finding that higher perceptual load reduced the amount of mind-wandering (i.e., internally-driven distraction).

    • This study replicated the earlier findings that both external and internal distractions are reduced under higher perceptual load.

 

Mind-Wandering

 

  • Perceptual Mind-Wandering:

    • The study investigated whether perceptual load impacts perceptual mind-wandering, such as imagery or daydreaming.

    • Findings: As perceptual load increased, the vividness of imagery during task-unrelated thoughts decreased.

    • Key Results:

      • There was a significant correlation (p < .001) between load levels and both the occurrence of mind-wandering and the vividness of mental imagery during tasks.

    • Individual Differences:

      • Propensities for voluntary imagery, spontaneous imagery, and mind-wandering were correlated with task-unrelated thoughts (TUTs) during tasks. However, these did not interact with perceptual load.

 

 

 

Cognitive and Perceptual Load

 

  • Cognitive Load:

    • Cognitive load increases distraction, opposite to the effects of perceptual load.

    • In experiments (Lavie et al., 2004), high cognitive load increased interference from irrelevant distractors in tasks (e.g., remembering six digits vs. one).

    • Flanker Task Findings: High cognitive load also increased distraction in this task, where participants had to remember digits while ignoring irrelevant visual information.

 

  • Awareness and Inattentional Blindness:

    • Higher perceptual load reduces distractor processing, increasing inattentional blindness (failing to notice something that one may want to notice).

    • In contrast, higher cognitive load increases distractor processing, which may reduce inattentional blindness.

 

Terminology in Attention Research:

 

  • Bottom-Up Attention:

    • Also known as stimulus-driven or exogenous attention, this form of attention is involuntary, triggered by external stimuli.

  • Top-Down Attention:

    • Refers to goal-driven or endogenous attention, which is voluntary and controlled by the individual’s objectives and cognitive control mechanisms.

 

Neuroimaging and Cognitive Control:

 

  • Brain Regions Involved in Attention:

    • Studies using fMRI have shown that frontal-parietal regions are activated during attentional control.

    • Specifically, the dorsolateral prefrontal cortex (DLPFC) and the anterior cingulate cortex (ACC) are critical in managing attention during tasks that require cognitive control.

 

 

 

 

 

Individual Differences in Attention and Cognitive Control:

 

  • Working Memory Capacity:

    • Individuals with higher working memory (WM) capacity experience less distraction, as demonstrated in Stroop tasks and dichotic listening tests, where those with higher WM detected their own names less often (an indicator of reduced distraction).

    • Mind-Wandering: Higher WM capacity correlates with reduced mind-wandering during attentionally demanding tasks. However, during low-perceptual-load tasks, individuals with high WM may experience more mind-wandering.

 

Key Findings in Load Theory

 

  • Cognitive vs. Perceptual Load:

    • Perceptual load reduces external and internal distractions, while cognitive load increases distractions.

    • This indicates that the type of task load (cognitive vs. perceptual) has opposite effects on attention and distraction.

  • Applications to Everyday Scenarios:

    • Searching for a friend in a crowd involves high perceptual load.

    • Performing complex calculations or solving problems involves high cognitive load.

 

Implications for Future Research:

 

  • The relationship between cognitive control mechanisms and mind-wandering is complex, and further research is required to untangle how different cognitive processes contribute to internal distractions.

 

Conclusion and Summary

 

  • Load Theory plays a pivotal role in understanding how perceptual and cognitive demands affect attention and distraction.

  • Neuroimaging has shown the involvement of frontal-parietal regions in managing attention.

  • Individual differences in cognitive control, such as working memory capacity, significantly impact distraction and mind-wandering.