Psychology Paper 1 Flashcards
1.1 Memory - Models of Memory
Cognitive psychologists study memory, but many of the things they’re interested in can’t be seen directly. For example, we know we have memory because we can remember why we went to the shop or how to use our phone—but we can’t actually see how memory works in the brain.
So, psychologists create models to help explain how memory might work. These models are like diagrams or theories based on what we already know. Once a model is made, more research is done to see if it’s correct. If the evidence supports it, the model is kept. If not, it’s changed or replaced with a better one.
This is exactly what happened with our understanding of memory. An early idea suggested we had two types of memory:
- Primary memory (short-term) for things we’re thinking about now
- Secondary memory (long-term) for things we store for later
Later, the multi-store model was created to explain memory in more detail. But as researchers found problems with that model, a new one was introduced: the working memory model, which gave a more detailed view of short-term memory.
1.1 Memory - Models of Memory Multi-Store Model of Memory
The multi-store model of memory is one of the most famous theory about how memory works. It was created by Atkinson and Shiffrin in 1968.
They suggested that memory works like a system where information flows through different stages or “stores”. Each store has a different job and is different in:
How it codes or stores information
How much it can hold (capacity)
How long it keeps information (duration)
1.1 Memory - Models of Memory Multi-Store Model of Memory, Sensory Register
Information from the world around us—everything we see, hear, touch, taste, and smell—first enters our sensory memory.
Sensory memory has different parts called sensory registers, and each one deals with a different sense:
Iconic register – for what we see (vision)
Echoic register – for what we hear (sound)
Haptic register – for what we touch (touch)
These registers work automatically. We can’t control what goes into them or how they work. They are constantly receiving loads of information—but way more than our brains can handle all at once.
To manage this, our brain uses attention to pick out the important information and ignore the rest.
Even though sensory registers can hold a lot of information, they only keep it for a very short time—just a couple of seconds or less—unless we pay attention to it. If we do focus on it, the information moves on to the next stage of memory.
1.1 Memory - Models of Memory Multi-Store Model of Memory, Iconic Register
The iconic register is the part of sensory memory that stores visual information, the iconic register is like a temporary picture memory.
It’s been studied a lot because:
It’s easier to test than some other senses
Vision is how we take in most of the information around us
The job of the iconic register is to help us make sense of all the fast-moving visual information we see, so it feels smooth and connected, not confusing or jumpy.
🧠 A helpful example:
Think of a cartoon.
Cartoons are made up of lots of still pictures shown quickly one after another. If you looked at each picture on its own, it wouldn’t make sense.
But when shown fast, your brain blends them together so it looks like one smooth scene.
The iconic register does something similar—it holds each visual image just long enough for the next one to come in, so your eyes and brain combine them into one clear, continuous experience.
1.1 Memory - Models of Memory Sperlings Experiment into Iconic Memory - Aim
Sperling wanted to find out how much information people can hold in their visual memory (iconic memory) and how long it lasts. He was interested in whether people can briefly take in more visual information than they can actually report.
1.1 Memory - Models of Memory Sperlings Experiment into Iconic Memory - Method
In his first experiment, Sperling quickly showed participants a grid of 12 letters arranged in three rows (like 3 rows of 4 letters). The display only appeared for 50 milliseconds (0.05 seconds). Participants were then asked to recall as many letters as they could from the whole display.
In a second experiment (called the partial report method), Sperling played a tone (high, medium, or low) immediately after showing the letter grid.
A high tone meant recall the top row
A medium tone meant the middle row
A low tone meant the bottom row
This tone told participants which row they needed to remember and report.
1.1 Memory - Models of Memory Sperlings Experiment into Iconic Memory - Results
In the whole report condition (no tone), participants could only recall about 4 or 5 letters, even though they said they had seen more.
In the partial report condition (with the tone), participants were able to recall around 75% of the letters in the cued row.
This showed that more information was briefly available in their memory, but it faded before they could report it all.
1.1 Memory - Models of Memory Sperlings Experiment into Iconic Memory - Conclusion
Sperling concluded that iconic memory can hold a lot of visual information, but only for a very short time—just a few hundred milliseconds. The reason people couldn’t recall everything in the first experiment was because the information faded too quickly before they had time to write it down or say it.
This study showed that iconic memory has a large capacity but very fast decay, which influenced later memory models like the multi-store model by Atkinson and Shiffrin.
1.1 Memory - Models of Memory Sperlings Experiment into Iconic Memory - Strength
Point (Strength):
One strength of Sperling’s study is that it was a laboratory experiment with a high level of control over variables.
Evidence:
For example, Sperling controlled exactly how long the letter grids were shown (50 milliseconds) and used specific tones to cue rows, making it easy to repeat the experiment under the same conditions.
Explain:
This high level of control means the study can be replicated by other researchers, which increases the reliability of the findings. In fact, similar studies have repeated Sperling’s method and found similar results, supporting the consistency of his conclusions about iconic memory.
Conclusion:
Therefore, Sperling’s study provides reliable evidence about the brief duration and large capacity of iconic memory, making it a strong foundation for models of memory like Atkinson and Shiffrin’s.
1.1 Memory - Models of Memory Sperlings Experiment into Iconic Memory - Weakness
Point (Weakness):
However, a key weakness is that the study was conducted in an artificial setting using unusual tasks.
Evidence:
For instance, people were asked to remember rows of random letters flashed on a screen for a fraction of a second—this is not how we normally use memory in real life.
Explain:
This makes the task low in ecological validity, meaning it doesn’t reflect real-world memory use, such as remembering faces, names, or tasks in everyday life. As a result, the findings may not fully apply to how iconic memory works outside the lab.
Conclusion:
So while the study is reliable, its validity is limited, and we should be cautious about generalising the results to real-world situations.
1.1 Memory - Models of Memory Multi-Store Model of Memory, Echoic Memory
Echoic memory is a type of sensory memory that holds sounds we hear. Research by Darwen et al. (1972) found that sounds stay in echoic memory for about three seconds, which is much longer than iconic memory (visual memory), which only lasts about half a second.
One reason echoic memory lasts longer may be because sounds—especially language—are really important for how we communicate and understand others (Cowan, 1984).
Darwen and his team tested this using an experiment similar to Sperling’s visual memory study, but with sounds instead of images.
- Participants listened to lists of letters and numbers played through headphones.
- One list sounded like it came from the left, one from the right, and one from behind.
- After hearing the lists, participants were given a sound cue telling them which list to remember.
The time between hearing the lists and getting the cue was changed between 0 and 4 seconds.
- The longer the delay, the worse the participants’ memory of the list.
- After 3 seconds, they couldn’t remember the cued list any better than without a cue at all.
They also found that cues based on content (e.g. asking participants to recall only letters or only numbers) didn’t help either. This shows that sounds in echoic memory are stored briefly in raw, unprocessed form, not by their meaning, until they’re moved into further memory processing.
1.1 Memory - Models of Memory Multi-Store Model of Memory, Short-Term Memory (STM)
Short-term memory (STM) is a temporary store that holds a limited amount of information currently being processed or consciously considered. According to Atkinson and Shiffrin’s multi-store model (1968), information from the sensory register that is given attention is transferred to STM. This memory store acts as a kind of “mental workspace,” maintaining information briefly unless it is actively rehearsed or encoded into long-term memory.
1.1 Memory - Models of Memory Multi-Store Model of Memory, Capacity of STM
The capacity of STM refers to the amount of information it can hold at any one time. Early research by Jacobs (1887) using the digit span technique found that participants could typically recall between five and nine items, establishing an average span of 7 ± 2 items. This concept was later supported by Miller (1956), who proposed that STM capacity is best understood in terms of “chunks” of information, rather than individual digits or letters. A chunk is a unit of information that may group multiple elements together (e.g., remembering “1999” as one chunk rather than four separate digits).
However, the concept of chunking has limitations. Simon (1974) demonstrated that the size of the chunks affects recall performance; participants recalled fewer large chunks (such as eight-word phrases) compared to smaller ones (e.g., two-word phrases). This indicates that capacity is not fixed in absolute terms, and varies depending on the complexity and familiarity of the information.
Further research by Cowan (2000) suggested that long-term memory influences performance in STM tasks, especially when sequences are repeated. This implies that digit span tasks may not measure “pure” STM. Additionally, Baddeley (1999) noted that reading sequences aloud may enhance performance due to temporary storage in the echoic memory, supporting the auditory nature of STM.
1.1 Memory - Models of Memory Multi-Store Model of Memory, Duration of STM
The duration of STM refers to how long information is retained without rehearsal. Atkinson and Shiffrin proposed that STM holds information for short periods unless it is transferred to long-term memory via rehearsal.
The classic study by Peterson and Peterson (1959) illustrated the limited duration of STM. Participants asked to recall three-letter sequences after varying delays, during which rehearsal was prevented, showed a rapid decline in recall. After 18 seconds, recall accuracy dropped to 5%, indicating that unrehearsed information in STM fades quickly.
Research also suggests that factors such as intention to recall and the nature of the material can influence STM duration. Sebrechts et al. (1989) found that when participants did not expect to be tested, recall dropped to 1% after only four seconds. Murdock (1961) demonstrated that when the information was more meaningful (e.g., a word rather than three unrelated letters), recall was significantly more resistant to decay.
These findings suggest that duration in STM is not fixed, but influenced by factors such as rehearsal, expectancy, and semantic meaning.
1.1 Memory - Models of Memory The Duration of Short-Term Memories - Aim
The aim of Peterson and Peterson’s (1959) study was to investigate the duration of short-term memory (STM). Specifically, they wanted to find out how long information can be held in STM when rehearsal is prevented.
1.1 Memory - Models of Memory The Duration of Short-Term Memories - Method
In a lab experiment, participants were shown consonant trigrams—three-letter combinations that do not form real words (e.g., LDH or CKX). Immediately after seeing a trigram, participants had to count backwards in threes from a given number (e.g., 358, 355, 352, etc.). This task was used to block mental rehearsal of the trigram. After different time delays—3, 6, 9, 12, 15, or 18 seconds—participants were asked to stop counting and try to recall the trigram. The procedure was repeated with different trigrams across trials to ensure reliable results.
1.1 Memory - Models of Memory The Duration of Short-Term Memories - Results
The findings showed a clear pattern: as the delay increased, recall accuracy decreased. After a 3-second delay, around 80% of trigrams were recalled correctly. However, recall dropped sharply over time. By 18 seconds, fewer than 10% of the trigrams were remembered. This demonstrated a rapid decline in memory retention without rehearsal.
1.1 Memory - Models of Memory The Duration of Short-Term Memories - Conclusion
Peterson and Peterson concluded that STM has a very limited duration when rehearsal is prevented. Information decays quickly from STM—often within 18 seconds or less—if it is not actively maintained. This study supported the idea that STM is a temporary memory store and that rehearsal is essential for keeping information available or transferring it into long-term memory.
1.1 Memory - Models of Memory Duration of Short-Term Memories - Weakness
Point:
A key weakness of Peterson and Peterson’s study is that it lacks ecological validity.
Evidence:
The task used in the study—recalling meaningless trigrams like “CKX” while counting backwards—is artificial and not something people encounter in everyday memory use.
Explain:
Because the stimuli were nonsense syllables with no personal meaning or context, the way memory was tested in the study does not reflect how we usually remember things in real-life situations, such as phone numbers or directions. This makes it difficult to generalise the findings to real-world memory processes.
Conclusion:
Therefore, while the study was well-controlled and useful for investigating the duration of short-term memory, its artificial nature reduces its external validity and limits how applicable the results are to everyday memory use.
1.1 Memory - Models of Memory Duration of Short-Term Memories - Strength
Point:
One strength of the Peterson and Peterson study is that it used a highly controlled laboratory experiment, which increases the internal validity of the findings.
Evidence:
The researchers carefully controlled variables such as the length of the consonant trigrams, the intervals between recall (3, 6, 9, 12, 15, or 18 seconds), and the use of a counting task to prevent rehearsal.
Explain:
These controls ensured that the only factor affecting memory performance was the delay before recall. This means the researchers could confidently conclude that the decrease in recall over time was due to the passage of time (duration), rather than other confounding variables. The use of standardised procedures also means that the study could be easily replicated, increasing its reliability.
Conclusion:
Therefore, the scientific design of the study strengthens the argument that information in short-term memory decays rapidly without rehearsal, supporting the idea of limited duration in STM.
1.1 Memory - Models of Memory Very Long-Term Memory - Strength
Point:
A strength of Bahrick et al.’s study is that it has high ecological validity.
Evidence:
The study tested real-life memories of participants’ high school classmates, using naturalistic materials like yearbook photos and names that held personal meaning to the participants.
Explain:
Because the memories being tested were meaningful and personally relevant, the study is more likely to reflect how memory works in everyday life. This contrasts with artificial memory tasks used in other studies (like Peterson and Peterson’s trigrams), making Bahrick et al.’s findings more generalisable to real-world memory use.
Conclusion:
This suggests that the study provides strong evidence for the long-lasting nature of real-life long-term memories, which remain accurate even decades after the original experience.
1.1 Memory - Models of Memory Very Long-Term Memory -Weakness
Point:
A weakness of Bahrick et al.’s study is the lack of control over extraneous variables.
Evidence:
Participants may have rehearsed the names and faces of classmates by looking at their yearbooks or keeping in contact over the years, which would strengthen their memory artificially.
Explain:
This means the accuracy of their memory might not be due to the durability of long-term memory alone, but instead influenced by repeated exposure or rehearsal. Therefore, it is difficult to isolate the true duration of long-term memory without accounting for these factors.
Conclusion:
As a result, the internal validity of the study is reduced, since other variables may have contributed to the high levels of recall and recognition observed.
1.1 Memory - Models of Memory Very Long-Term Memory - Aim
The aim of Bahrick et al.’s (1975) study was to investigate the duration of long-term memory (LTM), specifically how long memories for personal life events — such as the names and faces of former classmates — could be retained over time.
1.1 Memory - Models of Memory Very Long-Term Memory - Method
The researchers studied 392 participants who had graduated from a high school in America. The participants had left school at varying times, ranging from a few years to up to 48 years ago. The researchers used yearbooks from the participants’ schools to test their memory. They carried out several memory tests, including:
Photo recognition: identifying classmates from their pictures.
Name and face matching: matching names to the correct photos.
Free recall: recalling as many names of their classmates as they could without any visual or verbal cues.
This combination of tasks allowed the researchers to compare recognition (using cues) and recall (without cues).
