Cognition: Does Subthreshold Perception Affect Our Clothing Preference?

Our appreciation of clothes, of fabric, style, cut and make, is obviously dependent on our senses and perception. But perception is also guided by memory and our experience and knowledge of the world. One of the central factors in how we take in information from the outside world is our ability to select, and simultaneously to exclude, sources of information. The system that enables us to do this is attention.

One of the intriguing findings to emerge from a few decades of research on attention is that not all of the excluded information is lost. Even if attention is focused elsewhere, some of that excluded material gets into the brain and can influence our decisions. Kindly bear with me as I get into some details about the relevant cognitive psychology research. Once the cognition part has been laid out, I will get to clothes!

Subliminal Perception

In the nineteen-fifties, this area of research, on the perception of very briefly exposed stimuli, was called subliminal perception.

Many people remember the stories of advertisers flashing brief messages in a commercial (Drink Coke or Buy Ford), and the reports that Coke sales and Ford purchases were up as a result. There was even a science fiction story by JG Ballard called The Subliminal Man (Amazon), in which he explores the manipulation of the unconscious to create desire, through subliminal methods.

The initial results of the experiments were encouraging and seemed to support the phenomenon of briefly exposed information being perceived at a non-conscious level and influencing human behavior. But it was later shown that there were many serious methodological problems and flaws in the experiments. The idea fell away and scientists and people moved on.

Subthreshold Perception

In the 1980s, the phenomenon saw a revival in cognitive psychology, this time labelled subthreshold perception to distinguish it from the earlier studies – although limen/liminal and threshold literally mean the same thing! The fascinating new experiments by Anthony Marcel (Wikipedia), a British psychologist, were extremely well-controlled and carefully conducted, with multiple checks on possible confounding factors.

The results showed small but significant effects of information that could not possibly have been seen consciously, influencing the response times and accuracy of human subjects in these experiments. A brief and simplified description will give us some understanding of the basic approach.

Marcel Studies: Lexical Decision Task

Consider a task employed in the Marcel studies, the lexical decision task. The subject or participant in this task is shown two stimulus displays successively, each with a set of letters, and asked to decide whether the displays are legitimate words in the language. For instance SPOKE would be a word, FOLME would be a non-word.

To learn more or see lexical decision task examples, please see these videos on YouTube.

On some of the experimental trials, subjects were shown related words, for example NURSE and then DOCTOR. In others, an unrelated word pair, say CLOUD and then DOCTOR, would be shown. The response times were faster for DOCTOR when it was preceded by NURSE than when it was preceded by CLOUD.

This is not surprising when we think of human memory as an associative network of information. The word NURSE primed the system to activate related words in the subject’s memory, among which DOCTOR was one, and so it speeded the response to the latter. This process is an example of priming, when our processing system is modulated and directed to influence perception

Now consider the crucial extra twist that Marcel used in his design: He took the lexical decision task, and changed it by masking the first word in the pair with what’s called a noise mask. This is a collection of letter fragments in the same font as the words, jumbled together.

noise mask example
Example of a noise mask shown after a word or letter

When presented immediately after the first word, it effectively prevented the subject from seeing the first word. The interval of time between word and mask was determined separately for each subject in some control trials, so that we could be sure that they could not see any actual word consciously, behind the mask. This interval was on the order of tens of milliseconds. The masked display of the first word was done for all word pairs.

Backward Masking

For those curious, here’s a YouTube video that shows a few examples of backward masking:

For a deeper explanation of the above video, please see this video about the Phenomenology of backward masking.

Marcel Studies: The Results

The results were intriguing: Compared to unrelated word pairs, there was a significant speeding up of response to the second word, say DOCTOR, when preceded by a related but masked word, say NURSE. This was despite the established fact that the subject was not consciously aware of the first word – all they were aware of was the mask, which was presented for as much time as the second word, let’s say half a second.

Clearly, these results indicated that information from the masked first word was getting into the perceptual system without conscious awareness, and activating its meaning in a manner sufficient to help subjects respond faster to the second word.

There are many details and control aspects that I have left out in the above description to keep things simple. However, it should give you an idea of the thrust of this research. Information that we are not aware of at the time of presentation can still bypass the attentional filter and enter the processing stream, so to speak, and influence the subject’s decision on a subsequent task.

Subthreshold priming likely underlies the experience we have all had at times, that of déjà vu. It is the powerful feeling, as we are looking at or listening to something, that we have seen or heard it before. We may have seen it earlier but not been consciously aware of it – and it still influenced our response to the same or related information at a later time when we consciously took note of it.

Subthreshold Perception & Clothes

Here in the Ask Andy Community, we are interested in clothes.

How does the phenomenon of subthreshold perception, or subthreshold priming relate to clothes? One major way in which it can influence our perception is through the pickup of information about an ensemble even though we don’t consciously notice it.

Often people react to an ensemble of clothes that a model or another person is wearing, and very quickly form a first impression, whether good or bad. What informs this judgment is easy to understand – long experience with clothes which we like or dislike, combinations of color and texture, cut and style, in short, an entire history of experiences.

A substantial number of these experiences do not even begin to rise above the threshold of consciousness. Likewise, we do not consciously inspect all of the information present in the ensemble we are seeing before we pass the judgment of liking or disliking it. A lot of the processes involved are automatized. And automatization is something we do in many walks of life. Psychologists have studied it extensively.

Full Conscious Attention

Full conscious attention is expensive in terms of time and effort. So we automatize as many of the components of information processing as we can. As you are reading this article, consider what is in your conscious awareness. I’ll bet it is just meaning.

But remember, when you first learned to read as a child, reading was immensely effortful. Lines had to be put together into letters and those letters into words, those words sounded out, then meaning associated with each word. Plus all the syntactical rules of language playing a role in making sense of sentences! It is a miracle children learn to read and comprehend.

A lot of those initially effortful processes become automatized. In fact, most skilled performances have largely automatized components: Playing the piano, driving an automobile, riding a bicycle, and so on.

So we learn to judge clothes quickly, especially when items are in combination: Shirt, trousers, necktie, jacket or suit. We are processing information, often not consciously, about colour and texture and material and patterns and a host of other things, then coming to an overall judgment about the whole ensemble. Often we will hear people say there is something wrong with the ensemble but they can’t put their finger on it. It’s probably because what is wrong has been registered in a subthreshold way and is priming the conscious response of wrongness.

Does Subthreshold Perception Dictate Our Sartorial Decisions?

Does this awareness — that subthreshold processes take place — help in our sartorial decisions?

By knowing that there are details that could be initially hidden from awareness, we are better equipped to examine the information given to us through clothes and ensembles. We can begin to drill down deeper into our judgment and examine things closely and uncover the hidden details that may cause our judgments. We can understand our own and others’ response to clothes much better.

The complex histories that have brought us to our present set of criteria we use for evaluating clothes is another matter. This is where memory comes into play. Our habits are formed over a lifetime, and much that happens in the sartorial domain can modulate and change or solidify our responses to clothing. That can perhaps be discussed in another essay.

Terms defined

Subliminal Stimuli and Noise Masks

These are stimuli (words) that are presented for very brief durations, 20 milliseconds to 50 milliseconds, roughly, and they are followed by a noise mask (see below). The noise mask usually consists of letter fragments in the same font and size as the stimuli, so they effectively block the perception of the word.

Sometimes forward and backward masks are used in these stimuli, to tightly delimit the precise amount of time between onset of the (priming) word and its subsequent backward masking. So the forward mask is followed by the word, then by the backward mask. The forward mask can also be used by itself with the priming word quickly followed by the second target word.

More information: Wikipedia

Subthreshold Perception

Perception of stimuli at a non-conscious level (below the threshold of consciousness). This can also happen in the natural world when attention is focused on some part of the perceptual field but information from elsewhere gets into the information stream. The laboratory task with masks, etc., is an attempt to create a clear situation where all possibility of conscious perception of the priming stimulus is excluded.

Masked Priming Lexical Decision Task: An example of a Masked Identity Priming study can be found here.


  • Dixon, NF (1971)  Subliminal Perception: The Nature of a Controversy New York: McGraw-Hill.
  • Marcel, AJ (1983)  Conscious and unconscious perception: Experiments on visual masking and word recognition. Cognitive Psychology, 15, 197-237.

Note: The second reference is a fairly technical presentation.

Written by: Dr. Peter (drpeter)