When you encounter long lists—product listings, restaurant menus, or trivia facts—can you reliably remember every item? Most people cannot.
What they’re more likely to remember is a handful of items from the beginning or end of those lists. The reason for this is the serial position effect—a cognitive psychology concept that describes people’s tendency to remember the first and last items in a sequence more easily than the items in the middle.
If you work in ecommerce, you can use the serial position effect to your advantage. How your website presents your products, offers, and information can directly impact what shoppers remember and act on. Here are some ways to leverage the serial position effect to improve user experiences, build stronger brand recognition, and ultimately drive conversions.
What is the serial position effect?
The serial position effect is a phenomenon of human memory where people tend to recall the first and last items in a series—such as a list of words or numbers—better than the items in the middle. In experimental psychology speak, this means people show a cognitive bias toward items at the beginning or end of a list.
For example, imagine someone hears a list of grocery items—milk, bread, apples, cheese, cereal, and lettuce—and then later must recall as many words as possible. Studies show they’re more likely to recall “milk” and “lettuce” than they are to remember “apples” or “cheese.”
The serial position curve, which typically forms a U-shape, visually represents this phenomenon. This symbolizes how the first and last items promote strong free recall performance, while items presented in the middle of a list are less likely to be correctly recalled.
Origins of the serial position effect
German psychologist Hermann Ebbinghaus (1850–1909) was the first to describe the serial position effect, or how an item’s position within a sequence affects recall accuracy. After running a series of experiments on himself, he found that when he tried to memorize lists of made-up words, he could better recall the first few words and last few words than the words in the middle of his list.
How the serial position effect works
The serial position effect is a combination of two distinct memory processes: short-term memory (STM) and long-term memory (LTM). Cognitive psychology studies suggest that LTM powers a phenomenon known as the primacy effect, while STM powers a phenomenon called the recency effect.
Here’s how each of these works:
Primacy effect
The primacy effect is the cognitive bias where people tend to recall the first items in a list or sequence more accurately than items in the middle because people mentally review, or “rehearse,” the initial items multiple times at the beginning of a list when trying to memorize it. Each time they mentally rehearse previous items, there’s more of a chance that the items will transfer from a short-term store to a long-term store.
The information presented later in a list doesn’t get as many retention intervals, and it may be less likely to end up in a person’s long-term memory.
Recency effect
The recency effect is the complementary bias where people tend to remember the last items in a list or sequence with greater accuracy. The recency effect occurs because the information the person most recently received is typically still active and easily accessible in their short-term memory. Unlike previous items, these new informational nuggets haven’t yet faded from the immediate short-term store; as such, they are the easiest to retrieve.
Where to consider the serial position effect
Now that you understand the basics of the serial position effect, you can apply it to your business. If you have an online store, there are many ways to leverage the serial position effect for better user interfaces, clearer communication, and enhanced user experiences. Here are some specific applications:
Website/UX design
When you design your ecommerce website, place the most important product categories, promotions, or calls to action (CTAs) at the top or bottom of menus and lists, where users are most likely to remember them. For example, in an online clothing store, putting “New Arrivals” at the top of a navigation menu and “Sale” at the bottom makes them more memorable than if they were buried in the middle.
Content marketing
Put your strongest arguments or benefits at the beginning and end of blogs, product descriptions, or email campaigns. For example, in a blog post titled “Top 8 Ways to Use Our Product for Clean, Healthy Skin,” place the single best, most unique feature in Point No. 1 and the main CTA (e.g., “Get 15% off today”) in Point No. 8. This strategic positioning can exploit the brain’s storage mechanisms to maximize readers’ improved recall and motivation to act.
Advertising
Repeat your brand name, logo, or key message at both the start and finish of audio ads or TV commercials to lock them into people’s memories. You can also tailor the serial position effect to your chosen ad format. Design your ad copy, carousel ads, or video scripts to present the most significant offer or feature immediately and end with the most memorable message or unique selling proposition (USP).
Customer interactions
When it comes to support chats, calls, or customer onboarding, highlight key perks or offers at the opening and closing moments.
For example, say you have a customer support agent providing a list of benefits for a loyalty program. They should open with the highest-value benefit (e.g., “You’ll immediately get $100 in store credit”) and close with a simple, easy-to-execute CTA (e.g., “Just click ‘Enroll Now’ on your screen”). Your customer will be more likely to remember words the agent said at the beginning or end of the conversation, so make those words as impactful as possible.
Serial position effect FAQ
What is the serial position effect?
The serial position effect is a memory phenomenon where people are more likely to recall the first and last items in a list compared to those in the middle.
What is a real-life example of the serial position effect?
A real-life example of the serial position effect is when you remember the first and last items on a grocery list, but forget the ones in the middle. In ecommerce, the same effect happens when shoppers recall the first and last products in a category list while overlooking middle options.
What is the primacy and recency effect?
The primacy effect is the tendency to better remember the first items in a sequence because they receive more attention and go through more of your memory’s rehearsal processes, which moves a recalled item into your long-term memory. The recency effect is the tendency to better recall the last items since they remain active in your short-term memory.
What are the two components of the serial position effect?
The two components of the serial position effect are the primacy effect, where you remember early items better, and the recency effect, where you more easily recall later items.
