Optical Illusions That Make You Fatter and Your Wallet Lighter

“Eat from small plates, drink from taller glasses.” Optical illusions lead us to eat and drink more, as illustrated by the examples in this article. There’s an old saying in cuisine…”the first bite is with the eye.”

Interesting article. I’m not sure if there is empirical data to support it but it does show that our perception of our food can affect how much we eat. Our actions are affected by so many different things, many of which we might not be aware.

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The Modal Model of Memory and the Serial Position Effect

I’m continuing my recent trend of basic cognitive psychology posts. The following post is about the Modal Model of memory, which has been highly influential for a number of decades but it is slowly being modified over time. I won’t get into the more modern modifications of the modal model, rather, in my post I present the very traditional view of memory, even if it is somewhat controversial today. For example, a number of psychologists do not believe that short term memory really exists (working memory fills in the gap). In any case, my post serves as a brief introduction to a classic view of memory and of the primacy and recency effects.

The modal model of memory has three main components. They are: sensory register, short-term memory (STM), and long-term memory (LTM). This Atkinson and Shiffrin model of memory assumes that the processes of moving information from the sensory store to short-term and then long-term memory takes place in discrete stages. At any of these stages information can be lost through interference or decay. Another assumption of this model is that information processing has to start in the sensory register and be attended to, then move to STM, and then to LTM with rehearsal.

The serial position effect (split into the primacy and recency effects) is that the first few and last few items in a word list, for example, are the easiest to remember. A graph of this effect would be roughly parabolic (i.e., U-shaped). The primacy effect occurs because people have time to rehearse the first few items until the STM capacity is reached. The recency effect occurs because the last items are still in STM and have not decayed yet so they are easy to remember. The items in the middle of lists are easy to forget because STM capacity is too full for much rehearsal by then and as more items are presented, older items in STM are “pushed out.”

Serial Position EffectThere are ways to hinder the primacy or recency effects though. If items are presented rapidly then there is not time to rehearse the items and the primacy effect fades away. If there is a distracting task given at the end of the main task (similar to Peterson and Peterson’s 1959 study testing the decay rate of STM), then the recency effect disappears due to STM capacity being taken up by the distracters, which leads to decay of the information in STM. These findings indicate that the systems governing primacy and recency effects are separate. The findings also gave support to the modal model because researchers identified the primacy effect with the transfer of STM into LTM. The recency effect is just an example of information being in STM.

Word Superiority Effect and Parallel Processing

WordsOne experiment about cognitive brain functioning is the word superiority effect findings of Dr. Reicher in 1969. In this experiment either a word or a non-word (string of letters) is flashed on a screen. The subject is asked if the stimulus contained one of two letters, say a “C” or an “E”. When the stimulus did not resemble a word (e.g., XXCX) subjects were correct in identifying the target letter about 80% of the time. When the string of letters was similar to a word but not one (e.g., FELV) the subjects also correctly identified the target letter 80% of the time. However, the interesting finding was that when the stimulus was a word (e.g., TEND), subjects were correct in identification 90% of the time. So the word superiority effect is that subjects are most accurate in identifying a target letter when it is contained in a word as opposed to a string of letters.

This lends support to the theory that there are things that we can process in parallel and that that parallel processing (or parallel activation of word and letter) can be beneficial at times (such as helping subjects correctly identify individual letters more often when the letter is contained within a word rather than in a random string of letters). In other words, the whole word is recognized before all the letters individually are recognized. This then speeds up or aids processing because there are now a couple routes, per se, to that letter; there is the visual stimulus (seeing the letter) and the linguistic information (knowing that the letter is in the word) that both are activated and help people recognize letters better.

Image by uncommonmuse.