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Uncertainty in Multiclass Classification

Dr. Rishabh Pathak
1. What is Uncertainty in Classification? Uncertainty refers to the model’s confidence or doubt in its predictions. Quantifying uncertainty is important to understand how reliable each prediction is. In multiclass classification , uncertainty estimates provide probabilities over multiple classes, reflecting how sure the model is about each possible class. 2. Methods to Estimate Uncertainty in Multiclass Classification Most multiclass classifiers provide methods such as: predict_proba: Returns a probability distribution across all classes. decision_function: Returns scores or margins for each class (sometimes called raw or uncalibrated confidence scores). The probability distribution from predict_proba captures the uncertainty by assigning a probability to each class. 3. Shape and Interpretation of predict_proba in Multiclass Output shape: (n_samples, n_classes) Each row corresponds to the probabilities of ...
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Development of Prefrontal Cortex: Changes in PFC Functions

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Dr. Rishabh Pathak

The development of the prefrontal cortex (PFC) is characterized by significant changes in its functions across the lifespan, reflecting the maturation of cognitive control, executive function, and emotional regulation. Here are key aspects of changes in PFC functions during development:


1.     Early Childhood:

o    Emergence of Executive Functions: In early childhood, there is a gradual development of executive functions mediated by the PFC, including working memory, inhibitory control, cognitive flexibility, and goal setting. These functions support the regulation of attention, behavior, and emotions in young children.

o    Prefrontal Activation: Studies have shown increased activation in the PFC during tasks requiring cognitive control and decision-making in children, indicating the early maturation of PFC functions related to executive control.

2.     Adolescence:

o  Refinement of Executive Functions: During adolescence, there is continued refinement of executive functions and cognitive control processes mediated by the PFC. Adolescents show improvements in planning, problem-solving, impulse control, and decision-making abilities as the PFC undergoes structural and functional changes.

o    Increased Risk-taking Behavior: Adolescents often exhibit heightened risk-taking behavior and sensation-seeking tendencies, which are influenced by the development of the PFC and its role in evaluating rewards, inhibiting impulses, and considering long-term consequences.

3.     Adulthood:

o    Peak Cognitive Control: In adulthood, the PFC reaches peak efficiency in supporting cognitive control, working memory, and goal-directed behavior. Adults demonstrate enhanced abilities in complex decision-making, strategic planning, and emotional regulation, reflecting the mature functioning of the PFC.

o Integration of Information: The adult PFC is adept at integrating information from multiple sources, maintaining task sets, and coordinating cognitive processes across different regions of the brain. This integration supports higher-order cognitive functions and adaptive behavior.

4.     Aging:

o   Changes in PFC Activation: With aging, there may be changes in PFC activation patterns during cognitive tasks, reflecting alterations in neural efficiency and cognitive processing. Older adults may show differences in PFC functions related to working memory, attentional control, and response inhibition.

o Compensatory Mechanisms: Older adults may engage compensatory mechanisms involving recruitment of additional brain regions to support PFC functions, allowing for the maintenance of cognitive performance despite age-related changes in brain structure and function.

Understanding the developmental changes in PFC functions provides insights into the maturation of cognitive control, executive function, and emotional regulation across the lifespan. These changes reflect the dynamic interplay between brain development, experience, and environmental influences on higher cognitive processes mediated by the prefrontal cortex.

 

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