Selective and Visual Attention

Selective Attention

The term selective attention refers to the fact that we usually focus our attention on one or a few tasks or events rather than on many. This implies that we shut out other competing tasks. But how much information do we process about the things to which we are not paying attention?

To answer this question, cognitive psychologists use dichotic listening tasks,

Dichotic Listening Tasks: Dichotic listening tasks are experimental techniques used by cognitive psychologists to investigate how much information people process from unattended stimuli. In a typical dichotic listening task, participants wear headphones and receive different audio streams in each ear. They are instructed to focus on (or “attend to”) the message in one ear (the “attended channel”) and ignore the message in the other ear (the “unattended channel”).

Objective: The primary goal of these tasks is to understand the extent to which unattended information is processed. This helps answer the broader question of how selective attention works and what information, if any, is registered without conscious awareness.

Key Findings from Dichotic Listening Studies:

1. Limited Processing of Unattended Information: Early studies by Cherry (1953) found that participants could report little about the content of the unattended message, such as the language spoken or the specific words used. This suggested that unattended information undergoes minimal processing.
2. Processing of Physical Characteristics: Participants often notice physical changes in the unattended channel, such as a switch from a male to a female voice or changes in volume. This indicates that some basic physical properties of unattended information are processed.
3. Semantic Processing: More recent studies, such as those by Treisman (1960), showed that under certain conditions, some semantic processing of unattended information can occur. For instance, participants might notice if their name is mentioned in the unattended channel (a phenomenon known as the “cocktail party effect”), suggesting that highly relevant or salient information can break through the attentional filter.
4. Attenuation Theory: Ann Treisman proposed the attenuation theory, which suggests that instead of completely filtering out unattended information, the brain attenuates (weakens) it. This means that while unattended information is not entirely blocked, it is less likely to be processed deeply unless it is particularly significant or relevant.
5. Late Selection Theory: Deutsch and Deutsch proposed the late selection theory, which posits that all information (attended and unattended) is processed to a certain level of meaning before being filtered based on relevance. This theory suggests a more substantial role for the processing of unattended information compared to earlier models.

Implications: Dichotic listening tasks have provided valuable insights into the mechanisms of selective attention. They have helped cognitive psychologists understand:

• How attention filters information based on physical and semantic properties.
• The conditions under which unattended information might be processed.
• The balance between efficiency in focusing on relevant stimuli and flexibility in detecting important unattended information.

Overall, dichotic listening tasks reveal that while attention is selective, some unattended information can still be processed, especially if it is inherently significant or meaningful to the individual.

Broadbent’s Filter Theory and Dichotic Listening Task Findings

Broadbent’s Filter Theory: Donald Broadbent’s filter theory, proposed in 1958, is an early model of attention that suggests a mechanism by which information is selectively filtered before being processed for meaning. According to this theory, information from all stimuli enters a sensory buffer, but only the information that passes through a selective filter reaches higher-level processing and consciousness.

Core Concepts of Broadbent’s Filter Theory:

1. Sensory Buffer: All incoming information is temporarily held in a sensory buffer.
2. Selective Filter: A filter allows only certain information to pass through based on its physical characteristics (such as pitch, loudness, or location). This selection occurs before the meaning of the information is processed.
3. Higher-Level Processing: Information that passes through the filter is then processed for meaning and can enter conscious awareness.

Explaining Dichotic Listening Task Findings with Filter Theory:

1. Limited Processing of Unattended Information: Broadbent’s theory explains why participants in dichotic listening tasks report little about the unattended message. The filter is set to allow only the attended message to pass through based on its physical characteristics, effectively blocking the unattended message from reaching higher-level processing.
2. Processing of Physical Characteristics: Participants notice physical changes (e.g., a switch from a male to a female voice) in the unattended channel because these characteristics are processed in the sensory buffer before the filter. The filter selects information based on these physical traits, so changes in these traits can be detected even if the information is not fully processed for meaning.
3. Minimal Semantic Processing: According to the original version of Broadbent’s theory, semantic processing of unattended information is minimal or non-existent because the filter operates before meaning is assigned. This explains why detailed content from the unattended channel is not typically remembered.

Challenges to Broadbent’s Theory:

While Broadbent’s filter theory accounts for some findings in dichotic listening tasks, it faces challenges from certain observations that suggest some degree of semantic processing of unattended information:

1. Cocktail Party Effect: The ability of participants to notice their name in the unattended channel indicates that some semantic processing can occur without focused attention. This observation suggests that the filter might not be entirely rigid and that some unattended information can break through if it is particularly salient or relevant.
2. Attenuation Theory (Treisman): Ann Treisman proposed an attenuation theory as a modification to Broadbent’s model, suggesting that the filter attenuates (rather than completely blocks) unattended information. Attenuated information is less likely to be processed for meaning but can be if it is significant. This theory accounts for why participants might notice important unattended stimuli like their name.

Broadbent’s filter theory provides a foundational explanation for the selective nature of attention and why unattended information is typically not processed for meaning. However, findings from dichotic listening tasks, such as the cocktail party effect, have led to modifications of the theory, such as Treisman’s attenuation model, to better account for the occasional processing of unattended but significant information.

Models of Visual Attention

In cognitive psychology, there are at least two primary models that describe how visual attention functions: the spotlight model and the zoom-lens model. These models serve as metaphors for internal processes and help generate testable hypotheses. Visual attention generally operates as a two-stage process:

1. Initial Stage: Attention is distributed uniformly across the visual scene, and information is processed in parallel.
2. Focused Stage: Attention narrows to a specific area, and information is processed serially.

The Spotlight Model: The spotlight model, inspired by William James, likens attention to a spotlight with a focus, a margin, and a fringe. The focus is the high-resolution center where visual attention is directed. Surrounding this is the fringe, which gathers information in low resolution, extending to a certain margin.

The Zoom-Lens Model: Introduced in 1986, the zoom-lens model incorporates all the features of the spotlight model but adds the ability to change the focus size, similar to a camera’s zoom lens. This model suggests an inverse trade-off between the size of the focus and the efficiency of processing: a larger focus results in slower processing because the fixed attention resources are spread over a larger area. The minimum focus size can be as small as 1° of visual angle, though the maximum size is still undetermined.

Feature Integration Theory (FIT) vs. Attentional Engagement Theory (AET): A significant debate in the late 20th century compared Treisman’s Feature Integration Theory (FIT) and Duncan and Humphrey’s Attentional Engagement Theory (AET).

Feature Integration Theory (FIT):

• Preattentive Stage: Unconscious detection and separation of an item’s features (color, shape, size). This stage occurs early in cognitive processing without the individual’s awareness.
• Focused Attention Stage: Integration of these features into a cohesive perception of the object. Prior knowledge and cognitive mapping help combine features, as demonstrated by the case of R.M., who had Balint’s syndrome.

According to FIT, objects are identified through selective spatial attention that integrates features located in the same place into a unified object.

Attentional Engagement Theory (AET): AET suggests an initial parallel phase where all visual items in a scene are segmented and analyzed, forming structural representations. Selective attention then chooses which information enters visual short-term memory. This theory argues against the necessity of spatial attention for object detection, proposing that visual elements are initially encoded and bound together without focal attention. Attention is used to select among these pre-formed objects.

The contrast between FIT and AET highlights the complexity of visual attention, distinguishing tasks that rely solely on visual attention from those involving supplementary cognitive processes.

Neisser’s Schema Theory of Attention

Ulric Neisser, a pioneering cognitive psychologist, proposed a different perspective on attention known as schema theory. This theory departs from the idea of attention as a limited resource or a filtering mechanism. Instead, it emphasizes the role of cognitive schemas in guiding attention.

Core Concepts of Neisser’s Schema Theory:

1. Schemas: Schemas are mental frameworks or structures that organize knowledge and guide information processing. They represent patterns of thought or behavior that help individuals interpret and respond to the world.
2. Guided Search: Attention is guided by these schemas, which direct the focus towards relevant information based on past experiences, expectations, and current goals.
3. Top-Down Processing: Schemas influence attention in a top-down manner, meaning that higher-level cognitive processes (like knowledge and expectations) shape how sensory information is perceived and attended to.
4. Dynamic Interaction: There is a dynamic interaction between schemas and incoming sensory information. Schemas help interpret sensory data, and this data can, in turn, modify existing schemas or create new ones.

Definition and Impact of Multitasking: Multitasking involves attempting to perform two or more tasks simultaneously. Research shows that multitasking often leads to more mistakes and slower task performance. This is because attention must be divided among all the tasks being performed.

Divided Attention: Divided attention means focusing on multiple sources of information or performing more than one task at the same time. Classic studies have explored how well people can learn new information or perceive multiple tasks simultaneously, such as reading while listening or handling two different audio messages.

Research on Multitasking: Early studies looked at tasks like driving while tuning the radio or talking on the phone. Modern research often examines driving while performing other tasks, such as texting, eating, or talking to passengers or on a cell phone. Findings indicate that multitasking while driving leads to:

• More mistakes
• Harder and later braking
• Increased accidents
• Lane drifting
• Reduced situational awareness

Hands-Free vs. Hand-Held Phones: Studies show little difference in driving performance when using hands-free versus hand-held cell phones. The main issue is the cognitive strain on the attentional system, not the physical action of holding the phone.

Passenger vs. Phone Conversation: Talking with a passenger can be as demanding as talking on the phone. However, passengers can adjust their conversation based on driving conditions, while a phone conversation partner cannot.

Theories of Divided Attention:

1. Kahneman’s Theory:
   • Proposes a single pool of attentional resources that can be divided among tasks.
   • Considered too simple because it doesn’t account for different sensory modalities (e.g., visual, auditory).
2. Modality-Specific Model (Navon and Gopher, 1979):
   • Suggests that tasks using the same modality (like listening and writing) interfere with each other more than tasks using different modalities.
3. Resource Theory:
   • States that as tasks become automatic, they require fewer attentional resources.
   • Factors affecting divided attention include anxiety, arousal, task difficulty, and individual skills.

Multitasking often leads to decreased performance and increased errors due to the limited capacity of the attentional system. Understanding the limitations and factors influencing divided attention can help improve task management and safety in activities like driving.

The Stroop Task and Automaticity

The Stroop task is a classic experiment that demonstrates how a highly practiced task, such as reading, can become automatic and interfere with other tasks.

What is the Stroop Task? The Stroop task involves showing participants a list of words that are names of colors (e.g., “red,” “blue,” “green”), but the words are printed in colors that do not match their names. For example, the word “red” might be printed in blue ink. Participants are asked to name the color of the ink, not the word itself.

Demonstration of Automaticity:

1. Automatic Reading:
   • Reading is a highly practiced and automatic task for most literate individuals.
   • When participants see a word, their automatic response is to read the word rather than to focus on the color of the ink.
2. Interference Effect:
   • The Stroop task creates a conflict between the automatic process of reading the word and the task of naming the ink color.
   • This interference causes delays and errors as participants struggle to suppress the automatic reading response in favor of naming the ink color.
3. Controlled vs. Automatic Processes:
   • The Stroop task illustrates the difference between controlled processes (requiring conscious effort, like naming the ink color) and automatic processes (requiring little or no conscious effort, like reading).
   • The automatic nature of reading makes it difficult to ignore the word, demonstrating how practiced tasks can interfere with other tasks.

Significance in Cognitive Psychology: The Stroop task is used to study attention, processing speed, and the automaticity of cognitive processes. It shows how difficult it can be to override an automatic response, highlighting the interplay between automatic and controlled processing in the brain.

The Stroop task provides a clear example of how automatic processes can interfere with controlled tasks, emphasizing the power of automaticity in everyday activities. This experiment helps researchers understand the limits of attention and the challenges of multitasking, especially when automatic and controlled processes conflict.

Schneider and Shiffrin’s Visual Search Task and Automatic Processing

Background: Schneider and Shiffrin conducted a series of experiments using a visual search task to study automatic and controlled processing. Their work, published in the late 1970s, provided significant insights into how certain tasks can become automatic with practice.

Visual Search Task: In the visual search task, participants are asked to identify a target stimulus among a set of distractors. For example, they might be shown a series of letters and asked to find a specific letter (the target) among other letters (the distractors).

Two Types of Processing:

1. Controlled Processing:
   • Characteristics: Deliberate, effortful, and requires attention. It is typically used for new or complex tasks.
   • Example in Task: When participants are first learning the visual search task, they must consciously focus on identifying the target among the distractors.
2. Automatic Processing:
   • Characteristics: Fast, effortless, and does not require conscious attention. It develops with practice and repetition.
   • Example in Task: After extensive practice with the visual search task, participants can identify the target quickly and without much conscious effort.

Key Findings:

1. Development of Automaticity:
   • Schneider and Shiffrin found that with sufficient practice, tasks that initially required controlled processing could become automatic.
   • Participants were able to perform the visual search task faster and with fewer errors as they practiced, indicating the development of automatic processing.
2. Consistent Mapping vs. Varied Mapping:
   • Consistent Mapping: The target and distractors remained the same across trials. This consistency allowed participants to develop automaticity more easily.
   • Varied Mapping: The target and distractors changed across trials, requiring participants to use controlled processing more often because they could not rely on automatic recognition.
3. Impact on Performance:
   • In the consistent mapping condition, participants showed significant improvements in speed and accuracy over time, demonstrating the shift from controlled to automatic processing.
   • In the varied mapping condition, participants continued to rely on controlled processing, and improvements in performance were less pronounced.

Significance in Cognitive Psychology:

• Automatic vs. Controlled Processing: Schneider and Shiffrin’s research highlighted the distinction between automatic and controlled processing and provided a framework for understanding how tasks can shift from one type of processing to the other with practice.
• Practical Applications: Understanding automatic processing has practical implications in various fields, such as skill acquisition, training programs, and the design of user interfaces, where tasks can be designed to become more automatic and thus more efficient.

Schneider and Shiffrin’s visual search task experiments provided valuable insights into the nature of automatic and controlled processing. Their findings showed how repetitive practice could transform a task from being effortful and attention-demanding to being fast and automatic, enhancing our understanding of learning and cognitive processing.

Clinical Models of Attention

Attention is a fundamental cognitive function characterized by sustained focus on relevant information while filtering out distractions. It serves as a foundational process for various neurological and cognitive functions. Clinical models of attention, particularly those used in evaluating patients with diverse neurological pathologies, differ from theoretical investigation models.

Sohlberg and Mateer’s Model

One prominent clinical model used extensively in assessing attention in patients with brain injuries, particularly those recovering from coma, is the model developed by Sohlberg and Mateer. This hierarchical model outlines different levels of attentional activities that patients can engage in as they progress through their recovery process:

1. Focused Attention:
   • Involves responding discretely to specific sensory stimuli.
2. Sustained Attention (Vigilance and Concentration):
   • Requires maintaining a consistent behavioral response during continuous and repetitive activities.
3. Selective Attention:
   • Involves maintaining a behavioral or cognitive set in the presence of distracting or competing stimuli, emphasizing the ability to avoid distractions.
4. Alternating Attention:
   • Requires mental flexibility to shift focus between tasks that have different cognitive requirements.
5. Divided Attention:
   • Involves the ability to respond simultaneously to multiple tasks or task demands.

Utility and Application:

• Sohlberg and Mateer’s model is highly valuable for assessing attention across a wide range of pathologies. It correlates closely with daily life challenges faced by patients and guides the design of targeted rehabilitation programs, such as attention process training.

Other Descriptors for Types of Attention

1. Mindfulness:
   • Conceptualized as a clinical model of attention, mindfulness practices emphasize training attention functions and enhancing awareness. Mindfulness meditation is one technique used by clinicians to improve well-being, reduce anxiety, and improve the regulation of behavior. This involves period of sitting quietly, staying focused on one’s current experience, and being aware of the moment. Descriptions of the practice emphasize controlling mental focus—in short, controlling one’s attention.Research suggests that the regular practice of mindfulness meditation is correlated with higher satisfaction and other positive outcomes, and lower incidence of depression, absent-mindedness, and social anxiety.Neurologically, mindfulness is associated with activation of the prefrontal cortex and lower activity in the area of the amygdala.
2. Vigilant Attention:
   • Refers to the ability to sustain attention on non-arousing or uninteresting stimuli over extended periods. It requires maintaining focus despite the lack of inherent engagement, helping prevent distractions from other stimuli or tasks.

Clinical models of attention, exemplified by Sohlberg and Mateer’s hierarchical framework, provide structured assessments that guide rehabilitation efforts for patients with neurological impairments. Understanding different types of attention and their practical applications supports targeted interventions aimed at improving attentional capacities crucial for daily functioning and quality of life.