{"id":232,"date":"2016-04-28T20:19:49","date_gmt":"2016-04-28T20:19:49","guid":{"rendered":"http:\/\/labs.la.utexas.edu\/gilden\/?page_id=232"},"modified":"2016-04-28T20:24:51","modified_gmt":"2016-04-28T20:24:51","slug":"activated-memory","status":"publish","type":"page","link":"https:\/\/labs.la.utexas.edu\/gilden\/activated-memory\/","title":{"rendered":"Activated Memory"},"content":{"rendered":"

Activated Memory<\/em><\/strong><\/p>\n

We now have two useful facts.\u00a0 One is that melodic contour is an active construction in the mind of a perceiving animal.\u00a0 Take away the animal and all you have is variations in air pressure.\u00a0 The second fact is that this construction process has a constraint.\u00a0 It has to be fed notes sufficiently fast in order for them to be glued together as a melodic contour.\u00a0 This is not a constraint that applies to music alone.\u00a0 There is a global aspect of memory that seems to be bound up in a 2 second time scale.\u00a0 To get a feeling for what is going on here we are going to need a couple of facts about basic memory phenomena.<\/p>\n

Memory has not been studied systematically for very long.\u00a0 Although people have known they have memories for at least several thousand years, the first recorded memory experiment was conducted around 1890 by a German psychologist named Ebbinghaus.\u00a0 Nevertheless, people know a lot about memory because they can observe their own memory functions.\u00a0 Knowing about your own memory is something that starts occurring around the age of 10.\u00a0 Much of what I will discuss here you will already know but maybe not quite in the way that I will say it.<\/p>\n

The first and most important distinction in memory content is between declarative and procedural knowledge.\u00a0 Declarative knowledge consists principally of facts and states of affairs.\u00a0 For example you know that 1+1=2.\u00a0 That is in your memory.\u00a0 You don\u2019t have to refer to your fingers to verify it.\u00a0 When you first learned about counting you probably also had clear memories of what else you were doing that day, who taught you, and so on.\u00a0 All the personal issues surrounding 1+1=2 eventually get lost as we experience counting in a myriad of circumstances. Eventually all that is retrievable is the fact itself.\u00a0 Fact knowledge and personal autobiography compromise the greater part of awareness, but it is dwarfed in both scope and content by procedural knowledge. All of our motor skills are procedural.\u00a0 Knowing how to walk, how to put the spoon in the mouth, how to ride a bicycle, and so on are all procedural.<\/p>\n

Procedural knowledge is organized into schemas, patterns of action.\u00a0 These patterns begin with conscious awareness but eventually fade into the background as they become automatic.\u00a0 When you are learning to play an instrument all of these issues are quite obvious.\u00a0 For example, my trumpet teacher is quite keen on teaching me licks.\u00a0 For a long time I could not understand why because it seemed like an awful lot to learn and fairly useless besides.\u00a0 One of the first things I learned was that it is possible to play licks that I could not remember.\u00a0 This state of affairs can arise because there are procedural forms of memory that are unconscious as well as declarative forms that are in awareness.\u00a0 If I can consciously remember the first note, the rest of the notes in the lick often follow automatically.\u00a0 This is because the lick, as a motor memory trace, becomes activated by the action of a valve press.\u00a0 Often I find myself listening to the lick wondering how it comes out of me.\u00a0 Experienced musicians have enormous amounts of procedural knowledge in their fingers that awaits activation.\u00a0 They get this knowledge through practice.\u00a0 Practice turns declarative knowledge of the notes into unconscious motor patterns.<\/p>\n

There is one large difference between procedural and declarative knowledge.\u00a0 Procedural knowledge is organized at a very primitive level and does not generalize easily.\u00a0 Each lick or piece of music has to be practiced before it is in your fingers.\u00a0 Nothing comes for free.\u00a0 This is not true of declarative knowledge which is highly organized and consequently highly flexible and capable of rapid generalization.\u00a0 The memory system that accesses declarative knowledge is known as semantic memory.\u00a0 Semantic memory is organized similarly to the world wide web. All of our concepts live in a highly abstract network where the links are derived through association.\u00a0 The process of association is what guides thought and gives us the experience of stream of consciousness.<\/p>\n

Thought is pushed along the semantic network through a process that psychologists refer to as activation.\u00a0 The stream is diverted depending on which branches are active at any given moment.\u00a0 A simple example illustrates how thought is channeled.\u00a0 Consider the sentence \u201cHe dug with a spade\u201d.\u00a0 The word \u201cspade\u201d is actually fairly ambiguous but when you read that sentence hopefully you were thinking about shovels.\u00a0 Hopefully you were not thinking about cards.\u00a0 The word \u201cspade\u201d is associated with knowledge about cards as well as knowledge about digging and when you come across the action phrase \u201cHe dug\u2026\u201d it is the digging knowledge that gets activated.<\/p>\n

Memory activation is the way that animals like us gain access to our knowledge.\u00a0 And this is as true of the procedures we\u00a0 have automatized as the ideas that form the stream of thought.\u00a0 There are enormous reservoirs of information that lies dormant in permanent memory stores.\u00a0 At any moment we are using what is active.\u00a0 I am interested in the time course of memory activation and the theory that I am developing considers music and thought to be essentially governed by the same kind of activation process.\u00a0 The evidence that memory activation has universal properties comes from experiments like the one described in the next section.\u00a0 In the following experiment I will show how the duration of activation can be measured in semantic memory and we will see that it is pretty close to the 2 seconds that limits musical coherence.<\/p>\n

Previous: Measuring the Coherence Threshold<\/a><\/p>\n

Next: Measuring the Course of Activation Produced by Concepts<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

Activated Memory We now have two useful facts.\u00a0 One is that melodic contour is an active construction in the mind of a perceiving animal.\u00a0 Take away the animal and all you have is variations in air pressure.\u00a0 The second fact is that this construction process has a constraint.\u00a0 It has to be fed notes sufficiently […]<\/p>\n","protected":false},"author":107,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_uag_custom_page_level_css":"","footnotes":""},"class_list":["post-232","page","type-page","status-publish","hentry","entry"],"uagb_featured_image_src":{"full":false,"thumbnail":false,"medium":false,"medium_large":false,"large":false,"1536x1536":false,"2048x2048":false,"site-graphic":false},"uagb_author_info":{"display_name":"ecw255","author_link":"https:\/\/labs.la.utexas.edu\/gilden\/author\/ecw255\/"},"uagb_comment_info":0,"uagb_excerpt":"Activated Memory We now have two useful facts.\u00a0 One is that melodic contour is an active construction in the mind of a perceiving animal.\u00a0 Take away the animal and all you have is variations in air pressure.\u00a0 The second fact is that this construction process has a constraint.\u00a0 It has to be fed notes sufficiently…","_links":{"self":[{"href":"https:\/\/labs.la.utexas.edu\/gilden\/wp-json\/wp\/v2\/pages\/232","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/labs.la.utexas.edu\/gilden\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/labs.la.utexas.edu\/gilden\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/labs.la.utexas.edu\/gilden\/wp-json\/wp\/v2\/users\/107"}],"replies":[{"embeddable":true,"href":"https:\/\/labs.la.utexas.edu\/gilden\/wp-json\/wp\/v2\/comments?post=232"}],"version-history":[{"count":4,"href":"https:\/\/labs.la.utexas.edu\/gilden\/wp-json\/wp\/v2\/pages\/232\/revisions"}],"predecessor-version":[{"id":241,"href":"https:\/\/labs.la.utexas.edu\/gilden\/wp-json\/wp\/v2\/pages\/232\/revisions\/241"}],"wp:attachment":[{"href":"https:\/\/labs.la.utexas.edu\/gilden\/wp-json\/wp\/v2\/media?parent=232"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}