Frontal-Parietal Network (FPN)

The Frontoparietal Network (FPN) is a key brain network involved in cognitive control, goal-directed behavior, attention, and task management. The FPN is activated when individuals engage in externally oriented tasks, such as focusing on a particular goal, solving a problem, or maintaining attention in the face of distractions. This network is essential for flexible thinking and adaptive control of behavior, as it dynamically shifts attention between internal goals and external stimuli.

 

Key Brain Regions Involved in the Frontoparietal Network (FPN)

 

The FPN primarily involves interactions between the dorsolateral prefrontal cortex (DLPFC) and the posterior parietal cortex (PPC). These regions communicate with each other to enable high-level cognitive functions such as working memory, attention, and decision-making.

 

1. Dorsolateral Prefrontal Cortex (DLPFC) – Electrodes: F3 (Left), F4 (Right):

Function: The DLPFC, located in the frontal lobe, is critical for executive functions, including working memory, cognitive flexibility, planning, and decision-making.

Role in FPN: The DLPFC is responsible for maintaining task goals, selecting relevant information, and inhibiting distractions. It helps individuals focus on achieving specific objectives by keeping the goal in mind and adjusting behavior as needed.

 

2. Posterior Parietal Cortex (PPC) – Electrodes: P3 (Left), P4 (Right):

Function: The PPC, located in the parietal lobe, is involved in attention allocation, spatial awareness, and integrating sensory information.

Role in FPN: The PPC works with the DLPFC to direct attention to relevant sensory inputs and spatial locations. It helps prioritize external information based on its relevance to the task, enabling efficient decision-making and problem-solving.

 

3. Connections Between Prefrontal and Parietal Regions:

The FPN’s core function relies on the communication between the DLPFC and the PPC, allowing the brain to balance internal goals with external sensory inputs. The DLPFC generates the goal or task plan, while the PPC monitors the external environment to ensure that attention is properly directed toward task-relevant stimuli.

This interaction allows for adaptive cognitive control, meaning that the brain can quickly adjust its strategies and attention depending on the demands of the situation.

 

Flow of Information in the FPN

The Frontoparietal Network follows a bidirectional flow of information between the frontal and parietal regions, facilitating goal-directed behavior and attentional control.

 

1. Goal Setting and Planning (DLPFC – F3, F4):

The dorsolateral prefrontal cortex (DLPFC) is responsible for initiating goal-directed behavior. It forms the cognitive plan by setting a goal and developing strategies to achieve it.

At the start of a task, the DLPFC is highly active, organizing thoughts and identifying the steps required to accomplish the task.

 

2. Attentional Control and Prioritization (PPC – P3, P4):

The posterior parietal cortex (PPC) monitors the external environment and prioritizes sensory input that is relevant to the task at hand.

The PPC integrates sensory information from the visual, auditory, and somatosensory systems, ensuring that attention is directed to the correct stimuli in the environment. For example, while solving a math problem, the PPC helps focus on numbers and symbols while ignoring irrelevant background noise.

 

3. Feedback Loop for Dynamic Adjustment:

There is a feedback loop between the DLPFC and PPC that allows for real-time adjustment of behavior based on external inputs. As the PPC detects changes in the environment (such as new stimuli or shifting priorities), it sends signals back to the DLPFC, which updates the plan as necessary.

This feedback loop ensures that attention and behavior remain flexible and responsive to changes in the task or environment.

 

Functional Roles of the FPN

The Frontoparietal Network is critical for several cognitive functions, including:

 

1. Cognitive Flexibility:

The FPN allows the brain to switch between tasks or shift focus from one goal to another. This is crucial for adapting to new information or changes in the environment.

For example, if someone is interrupted while working on a task, the FPN helps them quickly refocus on the new task and, when ready, return to the original goal.

 

2. Working Memory:

The FPN supports working memory, which is the ability to hold and manipulate information in mind over short periods.

The DLPFC stores relevant information, while the PPC helps guide attention to this information and ensures that it remains accessible during the task. This enables tasks like mental math or remembering instructions.

 

3. Top-Down Attention Control:

The FPN enables top-down attention, which is the ability to control focus based on internal goals rather than being driven solely by external stimuli.

For example, while reading a book in a noisy environment, the FPN helps maintain focus on the text and block out irrelevant sounds.

 

4. Problem Solving and Decision Making:

The FPN is activated during complex problem-solving and decision-making tasks. The DLPFC formulates strategies, while the PPC evaluates the situation and identifies relevant information.

This collaboration allows for efficient decision-making, especially in situations where multiple solutions or approaches must be considered.

 

5. Task-Switching:

The FPN is essential for task-switching, allowing individuals to move from one task to another seamlessly. It helps prioritize tasks and shift cognitive resources as needed.

For example, when driving and simultaneously listening to directions, the FPN enables the brain to switch between focusing on the road and processing the spoken instructions.

 

Clinical Significance of the FPN

Disruptions or imbalances in the FPN have been associated with several cognitive and behavioral disorders. Some key clinical implications include:

 

1. Attention Deficit Hyperactivity Disorder (ADHD):

In individuals with ADHD, there may be dysfunctional connectivity within the FPN, particularly between the prefrontal and parietal regions. This can lead to difficulties with sustained attention, task-switching, and goal-directed behavior.

 

2. Schizophrenia:

Studies have shown that reduced connectivity in the FPN is associated with the cognitive deficits observed in schizophrenia, particularly in executive function, working memory, and cognitive flexibility.

 

3. Dementia and Cognitive Decline:

In neurodegenerative diseases like Alzheimer’s disease, disruptions in the FPN contribute to cognitive decline, especially in working memory and problem-solving abilities. Decreased FPN activity is linked to difficulties with goal-directed tasks and attention regulation.

 

4. Mood Disorders (Depression):

In depression, there may be hyperactivity in the DMN and underactivity in the FPN. This imbalance can lead to difficulty shifting focus from negative, self-referential thoughts (mediated by the DMN) to task-focused behavior (mediated by the FPN).

 

Summary of FPN Functionality

The Frontoparietal Network (FPN) is a flexible control system that balances internal goals with external sensory inputs, allowing for dynamic task management, attentional control, and cognitive flexibility.

Key brain regions involved are the dorsolateral prefrontal cortex (DLPFC) and the posterior parietal cortex (PPC), which interact to manage working memory, task prioritization, and attention.

 

The FPN’s flexibility in adapting behavior based on sensory input and goal orientation is critical for success in complex tasks, multitasking, and decision-making.

This network’s ability to switch between tasks and maintain attention makes it a central player in the brain’s cognitive control systems, especially in situations where rapid adjustments and focused attention are necessary.