Psychological influence / Social influence / Cognitive psychology

Suggestion Effect

Small cues can create large shifts in how people think, feel, remember, and act, especially when the situation is ambiguous or the source seems credible.

Popularity

Usefulness

Aliases

Suggestibility / Suggestion / Power of Suggestion / Indirect Suggestion / Hypnotic Suggestion

Domains

Psychology, social psychology, hypnosis research, psychotherapy, education, marketing, communication, memory research

Definition

The suggestion effect refers to a process where a person's thoughts, feelings, memory, perception, or behavior are influenced by direct or indirect cues, expectations, wording, authority, or context, often without explicit pressure.

Core Idea

People do not always respond only to facts. They may also respond to hints, expectations, labels, tone, framing, authority, or repeated cues.

How It Works

A suggestion provides a cue or expectation.
The person interprets the cue as meaningful.
Attention, belief, memory, or behavior shifts toward the suggested direction.
The influence is stronger when the source is trusted, the context is ambiguous, the person is highly suggestible, or the suggestion is repeated.

Usage Example

A teacher says, “This problem is tricky, but you are improving fast.” The student may approach the task with more confidence because the wording suggests progress and capability.

Famous Example

Example: Loftus and Palmer’s 1974 car-crash memory experiment. Participants watched films of traffic accidents and answered questions using different verbs. Those asked how fast the cars were going when they “smashed” into each other later reported higher speed estimates and were more likely to report seeing broken glass, even though no broken glass appeared in the film. (ScienceDirect)
Why it fits this rule: The wording of the question acted as a suggestion and influenced later memory reports.
Verification status: Verified as a published psychology experiment. However, it is more precisely classified as a leading-question / misinformation-effect example, not proof that all suggestions reliably change memory.

Use Cases / Situations Where It Applies

Education: teacher expectations, encouragement, classroom framing.
Therapy and clinical communication: careful use of reassurance, expectation, and suggestion.
Hypnosis: suggestion is central to hypnotic response. (APA Dictionary)
Marketing and product design: wording, labels, defaults, and social cues can shape perception.
Eyewitness questioning: leading questions can affect recall.
Leadership and management: expectations from authority figures can influence confidence and performance.

When Not to Use or Common Misuse

Do not treat suggestion as mind control.
Do not assume every behavior change is caused by suggestion.
Do not use manipulative, deceptive, or coercive suggestion.
Do not use suggestion as a substitute for medical, legal, or professional judgment.
Do not confuse “Suggestion Effect” with a single formal law; in English psychology, “suggestibility” and “suggestion” are more standard terms.

Rule Invention / Origin

Invented by: No single verified inventor.
Year of invention: Unknown as a single “effect”; the idea developed gradually.
Country / context of origin: Strong historical roots in 19th-century European hypnosis and psychotherapy research, especially French research around the Nancy School and Hippolyte Bernheim. Bernheim provided an influential theoretical account of hypnosis as heightened suggestibility in the 1880s. (Cambridge University Press & Assessment)

Evidence / Research Basis

Hypnosis research supports the role of suggestion in changing perception, sensation, action, and cognition. (ScienceDirect)
Memory research shows that misleading post-event information or leading questions can influence later recall, especially in classic misinformation-effect studies. (ScienceDirect)
APA defines hypnosis as a procedure or state in which suggestion is used to evoke changes in sensation, perception, cognition, affect, mood, or behavior. (APA Dictionary)

Short Practical Takeaway

Small cues can create large shifts in how people think, feel, remember, and act, especially when the situation is ambiguous or the source seems credible.