Human Behaviour and Mental Processes
Think of a person walking into a room, seeing a friend, smiling, and walking over to shake hands. What you just observed — the walking, the smiling, the handshake — is behaviour. It is outward, visible, and measurable. But what you did not see is everything that happened inside that person's mind: recognising the friend, feeling happy, deciding to approach, planning the handshake. That inner world — thoughts, feelings, memories, decisions — is the mental process.
The two are inseparable. Behaviour is the window through which we infer mental processes; mental processes are the engine that drives behaviour.
The Intuition
Imagine you are solving a math problem. Your behaviour is what someone else can see: you sit at a desk, you scribble on paper, you mutter numbers. Your mental processes are what only you experience: you recall a formula, you feel frustration, you hold a number in your working memory, you decide to try a different method.
Without the mental process, the behaviour is meaningless — a robot could scribble. Without the behaviour, the mental process is invisible — a dream no one else can witness.
Psychology studies both, but it can only directly observe behaviour. Mental processes are inferred from behaviour. This is why psychologists design careful experiments — to make the invisible visible.
The Precise Statement
Human behaviour refers to any observable action or response of an organism — from a blink to a speech to a complex social ritual. It is overt, measurable, and can be recorded.
Mental processes refer to the internal, subjective activities of the mind — thinking, feeling, remembering, perceiving, deciding, imagining. They are covert, private, and must be inferred.
Together, they form the subject matter of psychology. The discipline asks: How do mental processes give rise to behaviour? And how does behaviour shape mental processes?
A Simple Table to Hold the Distinction
| Aspect | Behaviour | Mental Processes |
|---|
| Nature | Overt, public | Covert, private |
| Example | Crying | Feeling sad |
| How we know it | Direct observation | Inference from behaviour or self-report |
| Measurable? | Yes (frequency, duration, intensity) | Indirectly (reaction time, brain scans, questionnaires) |
Why This Matters for Exams
Many students confuse the two. A common mistake is to say "thinking is behaviour" — it is not. Thinking is a mental process. The act of writing down the answer is behaviour. The thought that produced the answer is a mental process.
Do not write "behaviour includes thoughts" in an answer. Behaviour is observable action. Thoughts are mental processes. They are related but distinct.
The Core Takeaway
Human behaviour is what we do. Mental processes are what we think and feel. Psychology studies the link between them — how the inner world creates the outer action, and how the outer action reveals the inner world.
For any exam question: if you can see it, it is behaviour. If you can only experience it, it is a mental process.