How the stores differ

1. Three features tell the stores apart: duration, capacity and types of encoding.
2. Duration is how long information lasts in a store.
3. Capacity is how much information fits into it at once.
4. Types of encoding is the form the information is held in, such as sound or meaning.
5. Comparing the stores feature by feature shows that they are separate stores.

Duration and capacity of each store

1. Sensory store
   1. Duration is only a second or two, so information that is not attended to is lost at once.
   2. Capacity is limited to a brief snapshot of what each sense has just taken in.
   3. This store is also called the sensory register.
2. Short-term memory
   1. Duration is about 30 seconds without rehearsal.
   2. Capacity is about seven items, plus or minus two.
3. Long-term memory
   1. Duration can be a lifetime, so a memory from primary school can still come back.
   2. Capacity appears to be unlimited, with no point at which the store fills up.

Types of encoding

1. In the sensory store, information is held in the raw form of the sense that took it in, as an image for sight or a sound for hearing.
2. In short-term memory, information is encoded mainly acoustically, which means by sound.
3. In long-term memory, information is encoded mainly semantically, which means by meaning.

Evidence for separate stores

1. The three-store structure explains the differences in duration, capacity and encoding, and it makes predictions that can be tested in a laboratory.
2. Wilson, Kopelman and Kapur (2008) studied Clive Wearing, whose short-term memory was close to normal while his long-term memory was severely damaged.
3. He could hold a conversation in the moment, so his short-term memory was still working.
4. He scored close to nothing on tests of delayed recall, so new information was not reaching long-term memory.
5. That pattern supports the claim that the stores are distinct, each with its own duration and capacity.
6. The multi-store model was also the first to divide memory into separate stores, and later research was built on it.

Criticisms of the multi-store model

1. The model claims rehearsal is what transfers information into long-term memory, so more repetition should mean better recall.
2. Meaningful information often reaches long-term memory with no rehearsal at all.
3. A person remembers their GCSE results, or bad news about a relative, from a single hearing they never repeated.
4. Repeating a list of words in a language a person does not speak leaves those words hard to recall, so repetition alone does not secure a memory.
5. The criticism is therefore that rehearsal alone does not explain what is remembered, because meaning does much of the work.
6. A second criticism is that the supporting evidence leans on cases of brain damage, and one unusual case is a weak basis for claims about ordinary memory.

Turning this into marks

1. Take duration, capacity and encoding one at a time and run each one across all three stores, because a store-by-store description leaves the comparison marks unclaimed.
2. Because a general statement that it holds a little for a short time does not secure the knowledge mark, give the figures for short-term memory: about seven items and about 30 seconds.
3. Make the two evaluation points genuinely separate, naming Wilson, Kopelman and Kapur (2008) for support and rehearsal versus meaning against.
4. The mark most often lost is calling the model too simple without naming rehearsal versus meaning and giving one example remembered without repetition.