Encoding refers to the processing and making meaning of raw inputs of information in the mind.
It occurs through each sensory modality and is a necessary step for the brain to process information in working memory or commit to long-term storage.
Encoding frequently occurs throughout our lives, but some obvious examples of encoding include when we’re trying to learn vocabulary in a new language and squinting to see something on the horizon. In both instances, we’re well aware that our brains are searching for meaning from the sensory inputs around us.
Encoding in Psychology
Some scholarly definitions of encoding from psychology textbooks include:
“encoding refers to the intrapersonal process of transforming a perceived external stimulus into an internal representation” (Fiedler, 2011)
“When psychologists talk about encoding they are referring to the way the information is stored in memory.” (Eysenck, 2005)
Both definitions highlight that encoding is about taking external inputs and sorting them in our minds in order to ensure they are understood and remembered and the memory is retrievable at a later date.
Types of Encoding
There are several types of encoding:
- Acoustic: Inputting sounds or spoken words into memory. This is processed through the ears. Acoustic inputs can be processed in working memory or placed in long-term storage.
- Visual: Processing visual stimuli in iconic memory, which decays quickly; most visual stimuli are not committed to long-term memory.
- Tactile: Processing information regarding how something feels including texture, temperature, vibrations, and pain. The sense of taste is also tactile.
- Olfactory: Smells and odors are processed through the olfactory sensory system in the nasal cavity and can be committed to long-term storage.
- Semantic: Involves processing the meaning of concepts and declarative information in working memory; can be placed in long-term storage.
- The commercial has catchy lyrics and a cheerful upbeat rhythm that really sticks in your mind ─ Acoustic encoding
- The odor from the chemical spill immediately made people panic and look for ways to flee the city ─ Olfactory encoding
- Trying exotic foods in foreign lands can create lasting memories ─ Tactile taste encoding
- Listening to a professor’s lecture and thinking about how the material relates to yesterday’s class discussion ─ Semantic encoding
- The brand’s logo is bright and colorful and includes many shades of green that match their environmental image ─ Visual encoding
- You remember things far more effectively if you’re in the same space that you learned them – Encoding specificity principle
- As soon as the customer touched the pajamas and discovered how soft they felt, they had to buy a pair ─ Tactile encoding
- When passing by the bakery, the smell of fresh-baked bread and brewing coffee is almost irresistible ─ Olfactory encoding
- Reading another scientific paper for a psychology course ─ Semantic encoding
- Listening to classical music can help a person relax at the end of a stressful day ─ Acoustic encoding
- Visting an art gallery and gazing at the works of great impressionists Monet and Renoir ─ Visual encoding
Weaknesses of Mental Encoding
The process of encoding is inevitably the creation of interpretations of information. We have to rely in the future on our memories of events – encoded in our minds – which may be faulty.
Our memories tend to be faulty. We forget, misremember, mix up events and sequences, and subjectively interpret our experiences.
As Fincher and Robins argue:
“Encoding typically omits much of the richness of a stimulus/sensory experience and appears to primarily represent semantic content (meaning)” (Fincher & Robins, 2019)
So, mental encoding inevitably leads to a loss of accuracy, but nevertheless, assists us in remembering anything at all in the first place!
Today, to overcome this weakness, we often try to record events through video recordings, written records, and so on, so we can re-visit the events into the future.
Case Studies and Research Basis
1. Encoding Linguistic Information And Musicians
Encoding of music and language are usually attributed to the cerebral cortex. Speakers of tonal languages, such as Mandarin, have superior linguistic pitch pattern encoding compared to English-only speakers. Long-term exposure to linguistic pitch patterns found in tonal languages help explain this ability.
Wong et al. (2007) examined if music-related experience can enhance sensory encoding in the auditory brainstem. They measured the auditory brainstem functioning of musicians and non-musicians.
These measurements were taken while participants watched a video and listened to three randomly presented Mandarin stimuli.
Overall, the auditory brainstem regions of musicians “showed more faithful representation of the stimulus” (p. 421). This means this region encoded with a stronger correspondence to the properties of the stimuli.
“Musicians showed significantly better identification and discrimination” of tones as well (p. 421). Simply stated, “musicians have an enhanced ability to learn lexical tones…. These results complement our existing knowledge of the brainstem’s role in encoding speech” (p. 423).
2. Effects of Essential Oils On Cognitive Performance
Olfactory encoding can have pronounced effects on human behavior. From the ancient Greeks to modern societies, many have espoused the benefits of essential oils.
Unfortunately, as Moss et al. (2008) proclaim, “there has to date been limited scientific research into the validity of such reputed effects” (p. 60).
Exceptions include Martin (1996), who found that a vanilla-like odor reduced anxiety in patients undergoing CAT scans. While Ita et al. (2006) found lavender reduced anxiety of female patients with chronic haemodialysis (kidney treatment failure).
Moss et al. (2008) randomly assigned 144 volunteers to different aroma conditions: ylang-ylang, peppermint, or no aroma control. Cognitive performance was assessed using tests for spatial working memory, word recognition, and picture recognition, among several other measures.
The results showed that:
“Peppermint produced a significant improvement in overall quality of memory, compared to both control and ylang-ylang conditions” (p. 73).
In addition, speed of memory tests:
“…indicated that ylang-ylang slowed reaction times significantly compared to controls… ylang-ylang produced the slowest reaction times” (p. 73).
3. The Visual Sensory Register
The visual sensory register refers to the first step of encoding visual stimuli. Sperling (1960) was one of the first to study the visual sensory store and found that it lasts approximately 1/3rd of a second.
Sperling used a T-scope (tachistoscope) to present a picture card that displayed various letters: 3-7 letters on a single line, or 3 rows of 3 or 4 letters each.
The T-scope presented the image for 1/20th of a second, after which participants were asked to recall as many letters as possible. Most participants could recall 3-4 letters.
“The fact that observers commonly assert that they can see more than they can report suggests that memory sets a limit on a process that is otherwise rich in available information” (p. 26).
In other studies, Sperling presented a tone 1/3rd of a second or longer after the stimulus card disappeared. The longer the delay in the tone, the greater the decline in recall.
These findings suggest “Short-term information storage has been tentatively identified with the persistence of sensation…that of a rapidly fading visual image of the stimulus” (p. 26).
4. Encoding And Perception Of Taste
The sense of taste has survival value in most species. A sweet taste indicates the presence of sugar, which can provide the body with energy. A bitter taste, however, may serve as a warning of harmful chemicals.
According to neuroscientist David Hill, taste buds regenerate about every 10 days.
This leads to an interesting question regarding taste encoding, as Dr. Hill ponders:
“If taste cells are constantly turning over, how does the nervous system keep reliable information coming to the brain when the reception system is always changing?”
In addition to the well-known role of taste buds in encoding sensory information, areas of the brain are also important.
Research has shown that sweet and bitter tastes are processed in two distinct areas of the gustatory cortex. In a demonstration of how powerful the cortex is in taste perception, the National Institutes of Health describe a study that used cortical manipulations to alter taste preferences.
“Researchers showed that stimulation of the sweet cortical field could cause mice to prefer a bitter compound. Conversely, stimulation of the bitter cortical field triggered aversion to a sweet compound.”
5. Visual Encoding in the Classroom
Educational posters, student artwork, and theme-based decorations are common features of a well-designed classroom environment. However, there may be reason to believe that the presence of so much visual stimuli is counterproductive to learning.
Highly decorated classrooms have been described as “visual bombardment” (Bullard, 2010, p. 110) and a “cacophony of imagery” (Tarr, 2004, p. 1).
So much visual stimuli can be distracting to young learners and disrupt the encoding of semantic knowledge. To examine this possibility, Fisher et al. (2014) conducted short read-aloud classes with 24 kindergarten students.
Students participated in six lessons over a two-week period. Half were taught in a decorated classroom and half in a sparsely decorated classroom. All lessons were video-recorded and later coded for on-task and off-task behaviors.
All students took a test about the subject immediately after each lesson ended.
The results revealed that students:
“spent significantly more instructional time off task in the decorated-classroom condition than in the sparse-classroom condition…learning scores were higher in the sparse-classroom condition than in the decorated-classroom condition” (p. 6).
Encoding is the first step to processing stimuli from the environment. All sensory modalities have encoding systems that vary in how they function.
Although not well-studied, science has discovered that taste cells in the tongue regenerate fairly rapidly, while the areas of the brain that process those sensations do not.
Research on visual encoding indicates that it lasts less than a second. Unfortunately, too much visual stimuli can disrupt other forms of encoding. For example, kindergarten children learn less in classrooms with abundant visual stimuli.
On the other hand, some essential oils (peppermint) can improve memory, while others (ylang-ylang) can slow processing.
Interestingly, tonal languages are better encoded in the auditory brainstems of musicians than non-musicians.
As research progresses, more interesting findings regarding encoding will emerge that will enhance our understanding of the amazing human cortex. Which, most likely, will be applied to AI so that eventually humans will no longer need their brains.
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Eysenck, M. W. (2005). Psychology for AS level. New York: Taylor & Francis.
Fiedler, K. (2011). Social communication. New York: Psychology Press.
Fisher, A. V., Godwin, K. E., & Seltman, H. (2014). Visual environment, attention allocation, and learning in young children: When too much of a good thing may be bad. Psychological Science, 25(7), 1362-1370. Doi:
Fincher, S. A., & Robins, A. V. (Eds.). (2019). The Cambridge handbook of computing education research. Cambridge: Cambridge University Press.
Itai, T., Amayasu, M., Kuribayashi, N., Kawamura, M., Okada, A., Momose, T., Tateyama, K., Narumi, W., Uematsu, S., & Kaneko, T. (2000). Psychological effects of aromatherapy on chronic haemodialysis patients. Psychiatry and Clinical Neurosciences, 54(4), 393–397. Doi: https://doi.org/10.1046/j.1440-1819.2000.00727.x
Martin, G. N. (1996). Olfactory remediation: Current evidence and possible applications. Social Science and Medicine, 43, 63–70. Doi: https://doi.org/10.1016/0277-9536(95)00334-7
Moss, M., Hewitt, S., Moss, L., & Wesnes, K. (2008). Modulation of cognitive performance and mood by aromas of peppermint and ylang-ylang. International Journal of Neuroscience, 118(1), 59-77. Doi\; https://doi.org/10.1080/00207450601042094
Sperling, G. (1960). The information available in brief visual presentations. Psychological Monographs: General and Applied, 74, 1-29. https://doi.org/10.1037/h0093759
Tarr, P. (2004). Consider the walls. Young Children, 59(3), 1–5.
Wong, P. C., Skoe, E., Russo, N. M., Dees, T., & Kraus, N. (2007). Musical experience shapes human brainstem encoding of linguistic pitch patterns. Nature Neuroscience, 10(4), 420–422. https://doi.org/10.1038/nn1872