hey everyone welcome back to Verity mind this video is part three exploring the multi-star model of memory in the previous videos we've explored the structure and processes of memory according to the model and considered each star in terms of its coding capacity and duration this video is now going to evaluate the multi-store model so let's consider two pieces of evidence that support the multi-style model firstly the Primacy and recency effect researchers found that when people are presented with a list of items to recall in order participants often Begin by recalling the items at the end of the list known as the recency effect because these items are still in short-term memory and then people recall the items at the beginning of the list known as the Primacy effect because these are thought to have been transferred to long-term memory with some rehearsal however the items in the middle have been forgotten or we could say displaced because short-term memory has a limited capacity so the new more recent items push out the middle items from short-term memory this Primacy and recency effect nicely demonstrates the idea of separate stores for short-term and long-term memory and thus supports the multi-star model other supporting research comes from one of the most famous and studied individuals in the history of psychology a man known by many a psychology student around the world his patient hm during his childhood hm had been involved in a bicycle accident which resulted in hm developing epilepsy many of the seizures he experienced worsened to the point where medication was having little impact and left him with the option of surgery however when hm had specific parts of his brain removed notably the hippocampus whilst it helped reduce his symptoms it left him with problems with his memory in short hm was unable to form any new long-term memories he could remember things before the surgery but he couldn't form memories after the surgery his short-term memory was fine but he couldn't transfer any of this information to long-term memory the case study of hm provides further support for the multi-star model as it demonstrates that there are separate stores for short-term memory and long-term memory however the multi-star model can be criticized because of the artificial tasks often used in their lab experiments this is because in trying to study memory in a way that is measurable and controlled it means that the tasks participants are given are often very different from how our memory typically functions for example Peterson and Peterson study into the duration of short-term memory through the use of random consonants known as trigrams and then being presented with a three-digit number that you have to count backwards from probably isn't the task you've done before and is certainly not typical of the way we might use our memory on a day-to-day basis this is a problem because it limits the extent to which the findings from such research can be generalized beyond the laboratory setting therefore the multi-star model could be questioned because it's based on Research that lacks ecological validity another limitation with the multi-star model is that it oversimplifies long-term memory the multi-store presents long-term memory as a unitary store in other words a single unit however the multi-star model has been criticized for proposing an oversimplified view of long-term memory as further research has demonstrated that there are separate parts to long-term memory these include procedural memories these are memories for actions and motor skills such as how to tie your shoelace or ride a bike episodic memories these are memories of personal experienced events for example what you did on your birthday last year and then there are semantic memories these are memories for knowledge or fact-based information for example the capital of Sweden is Stockholm therefore because the multi-star model lacks detail about separate types of long-term memory its ability to fully explain how memory Works can be questioned a final limitation with the multi-star model is that it oversimplifies short-term memory this is because further research has demonstrated that there are separate parts to short-term memory for example there is the case study of KF who is involved in a motorcycle accident not to be confused with hm who is involved in a bicycle accident this accident resulted in damage to his short-term memory specifically with verbal recall when tested he was only able to recall two items verbally from short-term memory in other words if someone read aloud a list of items for example a shopping list he would only be able to remember two things on the list in contrast when he's short to memory was tested with visual information his recall was mostly unaffected as a result this case study suggests that short-term memory may have further components to it perhaps for verbal and visual information in fact next we're going to explore the working memory model which was specifically developed to explore the different parts of shorter memory that we may possess to watch that click the video on the screen now I hope you found this video helpful and we'll see you in the next one