The Myers Briggs Function Test goes beyond the basic 16 personality types by exploring the underlying psychological mechanisms that shape how people think, feel, and behave. This approach focuses on the eight cognitive functions—mental processes first identified by psychologist Carl Jung and later adapted by Isabel Briggs Myers into the MBTI framework.

While the traditional MBTI test identifies your type (such as INTJ or ESFP), the Myers Briggs Function Test dives deeper into how your mind operates—revealing the unique hierarchy of functions that drive your personality and decision-making style.

What Is the Myers Briggs Function Test?

The Myers Briggs Function Test is an assessment that identifies which cognitive functions are dominant, auxiliary, tertiary, and inferior within your personality type. Each MBTI type is defined by a specific order of these functions, which influence everything from how you process information to how you relate to others.

Rather than simply telling you whether you’re an introvert or extrovert, this test explains *how* you think and what kind of reasoning or perception guides your worldview.

The 8 Cognitive Functions in the Myers Briggs Function Test

The Myers Briggs model is based on eight core cognitive functions, divided between two types of mental processes—perceiving and judging—and expressed either in an introverted or extraverted way.

The Eight Functions Are:

  • Extraverted Thinking (Te): Focuses on logic, organization, and objective problem-solving. Prefers efficiency and results.
  • Introverted Thinking (Ti): Seeks internal logical consistency and deep understanding of systems and concepts.
  • Extraverted Feeling (Fe): Values harmony, empathy, and the emotional needs of others. Seeks social connection and approval.
  • Introverted Feeling (Fi): Guided by internal values and authenticity. Prioritizes personal morals and emotional integrity.
  • Extraverted Intuition (Ne): Explores possibilities and patterns in the external world. Curious and imaginative.
  • Introverted Intuition (Ni): Focuses on abstract ideas, symbolism, and long-term insights. Seeks meaning beneath the surface.
  • Extraverted Sensing (Se): Engages with the present moment through physical experience. Values action and sensory stimulation.
  • Introverted Sensing (Si): Relies on memory, familiarity, and tradition. Prefers routine and practical stability.

How the Myers Briggs Function Test Works

When you take the Myers Briggs Function Test, it evaluates your preferences for perception (how you take in information) and judgment (how you make decisions). Based on your responses, it determines the hierarchy of cognitive functions that form your personality type.

Each of the 16 MBTI types has a unique function stack composed of four main functions:

  • Dominant Function: The most natural and powerful aspect of your personality.
  • Auxiliary Function: Supports and balances your dominant function.
  • Tertiary Function: Develops later in life and adds flexibility.
  • Inferior Function: The least developed; often operates unconsciously or under stress.

Examples of Function Stacks in the Myers Briggs Function Test

Below are examples of how the cognitive functions combine in different MBTI personality types according to the Myers Briggs Function Test:

  • INTJ: Dominant – Introverted Intuition (Ni); Auxiliary – Extraverted Thinking (Te); Tertiary – Introverted Feeling (Fi); Inferior – Extraverted Sensing (Se).
  • ENFP: Dominant – Extraverted Intuition (Ne); Auxiliary – Introverted Feeling (Fi); Tertiary – Extraverted Thinking (Te); Inferior – Introverted Sensing (Si).
  • ISTP: Dominant – Introverted Thinking (Ti); Auxiliary – Extraverted Sensing (Se); Tertiary – Introverted Intuition (Ni); Inferior – Extraverted Feeling (Fe).
  • ESFJ: Dominant – Extraverted Feeling (Fe); Auxiliary – Introverted Sensing (Si); Tertiary – Extraverted Intuition (Ne); Inferior – Introverted Thinking (Ti).

Each personality type uses its functions in a specific order, shaping the individual’s perspective, decision-making process, and communication style.

Understanding Function Dynamics in the Myers Briggs Function Test

Every personality type in the Myers Briggs Function Test relies on a dynamic relationship between its functions. The dominant and auxiliary functions represent the individual’s core strengths, while the tertiary and inferior functions create areas for personal growth.

Here’s a breakdown of these internal dynamics:

  • Dominant Function: Defines your comfort zone and how you naturally engage with the world.
  • Auxiliary Function: Helps you balance your dominant traits by introducing a contrasting perspective.
  • Tertiary Function: Adds depth and balance, usually emerging during adulthood.
  • Inferior Function: Often a hidden weakness or area of struggle but becomes a key driver of self-improvement when developed.

Why the Myers Briggs Function Test Matters

While the basic MBTI provides an overview of personality types, the Myers Briggs Function Test reveals the *why* behind your type. It explains not just your preferences but your mental wiring—offering deeper insight into your motivations, strengths, and blind spots.

Some key benefits include:

  • Deeper self-awareness: Understand your cognitive strengths and how they influence your behavior.
  • Improved communication: Recognize how others process information differently.
  • Personal development: Identify areas where you can grow by strengthening your weaker functions.
  • Career insight: Align your work style and career path with your natural cognitive preferences.

Using the Myers Briggs Function Test for Growth

Personal development through the Myers Briggs Function Test involves becoming aware of all your functions—not just your dominant ones. As people mature, they often begin to balance their dominant and inferior traits, leading to more emotional intelligence and adaptability.

For instance, an INTJ may strengthen their inferior Se (Extraverted Sensing) by becoming more present and action-oriented, while an ESFP might develop their Ni (Introverted Intuition) to enhance long-term planning.

Final Thoughts

The Myers Briggs Function Test offers a deeper, more nuanced understanding of personality by focusing on the eight cognitive functions that drive human thought and behavior. It’s not just about labeling personality types—it’s about uncovering how your mind truly works.

By exploring your cognitive function stack, you can better understand your motivations, improve your relationships, and unlock your potential for personal growth. Whether you’re an intuitive strategist, a logical problem-solver, or an empathetic communicator, the Myers Briggs Function Test helps you see the deeper layers of your personality with clarity and confidence.