Designing with the mind in mind
CHAPTERS 1 - 14
Psychology of Interaction Design
Author:
Jeff Johnson
,Designing with the mind in mind Jeff Johnson
Chapter 1: We perceive what we expect
Our expectations -and therefore our perceptions- are biased by three factors:
- the past: our experience
- the present: the current context
- the future: our goals
PERCEPTION BIASED BY EXPERIENCE
Perceptual priming: Priming the mind can affect perception. Priming can be visual, but it can also
bias other types of perception, such as sentence comprehension.
Familiar perceptual patterns or frames: Repeated exposure to each type of situation builds a
pattern in our minds of what to expect to see there. These frames include the objects or events
that are usually encountered in that situation.
Mental frames for situations bias our perception to see the objects and events expected in each
situation. They are a mental shortcut.
Mental frames also make us see things that aren’t really there.
“Place controls consistently” is a common user interface design guideline.
Habituation: Repeated exposure to the same (or highly similar) perceptions dulls our perceptual
system’s sensitivity to them.
Social media fatigue: sooner or later people get tired of wasting time reading about every
little thing that their friends do or see.
Attentional blink: Another low-level biasing of perception by past experience occurs just after we
spot or hear something important. It is thought to be caused by the brain’s perceptual and attention
mechanisms being briefly fully occupied with processing the first recognition.
PERCEPTION BIASED BY CONTEXT
Perceptions in any of our five senses may affect simultaneous perceptions in any of our other
senses.
McGurk effect: you will hear the syllable indicated by the speaker’s lip movement rather than the
syllable actually in the audio.
Ventriloquism: Ventriloquists don’t throw their voice; they just learn to talk without moving their
mouths much. Viewers’ brains perceive the talking as coming from the nearest moving mouth: that
of the ventriloquist’s puppet.
Illusory flash effect: When a spot is flashed once briefly on a display but is accompanied by two
quick beeps, it appears to flash twice. Similarly, the perceived rate of a blinking light can be
adjusted by the frequency of a repeating click.
2
, Designing with the mind in mind Jeff Johnson
PERCEPTION BIASED BY GOALS
Our goals filter our perceptions: things unrelated to our goals tend to be filtered out pre
consciously, never registering in our conscious minds.
Our goals:
- Guide our perceptual apparatus, so we sample what we need from the world around us.
- Filter our perceptions: things unrelated to our goals tend to be filtered out pre-consciously,
never registering in our conscious minds.
When screening text on a website, users don’t simply ignore items unrelated to their goals; they
often don’t even notice them.
Cocktail party effect: if you are conversing with someone at a crowded party, you can focus your
attention to hear mainly what they are saying. The more interested you are in the conversation, the
more strongly your brain filters out surrounding chatter. If you are bored by what your
conversational partner is saying, you will probably hear much more of the conversations around
you.
Children are more stimulus driven: their perception is less filtered by their goals. This makes them
more distractible than adults, but also makes them less biased as observers.
Mechanisms by which our current goals bias our perception:
- influencing where we look
- Sensitising our perceptual system to certain features
DESIGN IMPLICATIONS
These sources of perceptual bias have implications for user interface design:
- Avoid ambiguity
- Be consistent
- Understand the goals
3
CHAPTERS 1 - 14
Psychology of Interaction Design
Author:
Jeff Johnson
,Designing with the mind in mind Jeff Johnson
Chapter 1: We perceive what we expect
Our expectations -and therefore our perceptions- are biased by three factors:
- the past: our experience
- the present: the current context
- the future: our goals
PERCEPTION BIASED BY EXPERIENCE
Perceptual priming: Priming the mind can affect perception. Priming can be visual, but it can also
bias other types of perception, such as sentence comprehension.
Familiar perceptual patterns or frames: Repeated exposure to each type of situation builds a
pattern in our minds of what to expect to see there. These frames include the objects or events
that are usually encountered in that situation.
Mental frames for situations bias our perception to see the objects and events expected in each
situation. They are a mental shortcut.
Mental frames also make us see things that aren’t really there.
“Place controls consistently” is a common user interface design guideline.
Habituation: Repeated exposure to the same (or highly similar) perceptions dulls our perceptual
system’s sensitivity to them.
Social media fatigue: sooner or later people get tired of wasting time reading about every
little thing that their friends do or see.
Attentional blink: Another low-level biasing of perception by past experience occurs just after we
spot or hear something important. It is thought to be caused by the brain’s perceptual and attention
mechanisms being briefly fully occupied with processing the first recognition.
PERCEPTION BIASED BY CONTEXT
Perceptions in any of our five senses may affect simultaneous perceptions in any of our other
senses.
McGurk effect: you will hear the syllable indicated by the speaker’s lip movement rather than the
syllable actually in the audio.
Ventriloquism: Ventriloquists don’t throw their voice; they just learn to talk without moving their
mouths much. Viewers’ brains perceive the talking as coming from the nearest moving mouth: that
of the ventriloquist’s puppet.
Illusory flash effect: When a spot is flashed once briefly on a display but is accompanied by two
quick beeps, it appears to flash twice. Similarly, the perceived rate of a blinking light can be
adjusted by the frequency of a repeating click.
2
, Designing with the mind in mind Jeff Johnson
PERCEPTION BIASED BY GOALS
Our goals filter our perceptions: things unrelated to our goals tend to be filtered out pre
consciously, never registering in our conscious minds.
Our goals:
- Guide our perceptual apparatus, so we sample what we need from the world around us.
- Filter our perceptions: things unrelated to our goals tend to be filtered out pre-consciously,
never registering in our conscious minds.
When screening text on a website, users don’t simply ignore items unrelated to their goals; they
often don’t even notice them.
Cocktail party effect: if you are conversing with someone at a crowded party, you can focus your
attention to hear mainly what they are saying. The more interested you are in the conversation, the
more strongly your brain filters out surrounding chatter. If you are bored by what your
conversational partner is saying, you will probably hear much more of the conversations around
you.
Children are more stimulus driven: their perception is less filtered by their goals. This makes them
more distractible than adults, but also makes them less biased as observers.
Mechanisms by which our current goals bias our perception:
- influencing where we look
- Sensitising our perceptual system to certain features
DESIGN IMPLICATIONS
These sources of perceptual bias have implications for user interface design:
- Avoid ambiguity
- Be consistent
- Understand the goals
3
