July 27, 2004 Test Material = Don't need uses of psycho active drugs; and neural pathways. Wednesday August 9th = Les Guiles lecture Test three will be 7, 8, 11, 12 ---------------------------------------------------------------------------- Learning and Memory... The "Hallmark" of psychology. It was the beginning and it has maintained it self in a place of prominence in psychology. - How do individuals (at least single celled organisms) learn things... - What are underlying mechanisms that support these - How can we use those to our advantage Learning and Memory is happening all the time. Children learn all the time. - Object permanents : it no longer knows that something exists when it can't see it. - Unconscious forms of learning/ Conscious forms etc... You were good or bad at learning things. We could have subdivided memory into one of four categories based on time. Iconic Memory (Perceptual) - Perceptual systems remember the stimulus.. (Memory is defined as some behavior in the future being different becuase of a previous experience. Where behavior is defined as overt behavior or behavior that you contemplate.) - Ex: Looking at sun; looking away and still seeing light. - This memory is very very brief. It lasts no more than a second or two. Usually milliseconds. Short Term Memory - Lasts a few seconds (if you're not actively rehearsing something) - For something to get into Short Term there usually has to be some sort of iconic memory trace. - If you wanna keep something in short term memory for a while you have to rehearse it. - If something is relatively salient its shuffled over to.... Intermediate Memory - Usually lasts about thirty or fourty minutes. - When it gets here is undergoes a process called consolidation. It seems to be rehearsed; contemplated; reviewed. You begin to try and put things together. If this is succesful.... Long Term Memory - Can last Years to a lifetime. - Fairly Resistant to insult. The most vulnerable point in memory is the Intermediate stage. If you disrupt the consolidation. Then it never makes it to long term. Stress is one of the best things to disrupt the consolidation process. Memory was all lumped together. The only seperating factor was the time at which the event occured. If memory was divided by things that were on a list; they would be remembered like this.... Beginning Middle End <---------I-----------------I--------------------I--------> remembered: Good Bad Good Also we realized that there are limits to how much can be memorized or learned at one time. Most people average around 5-9 Things that can be really memorized at once. We can also chunk that information into groups - Phone numbers are chunked information area code; prefix; number. People also form "scripts" which is certain associations that are held for certain things. Information is strung together. Ex: child's association with his aunt is her hobbie of knitting. Childhood amnesia: Memory is lost from childhood area almost entirely. - One of the reasons we think we remember is family stories and pictures that encode the information. All the above was completely relevant until about 1957. H.M. has etractable eppilepsy; pharmacological cures didn't work; most of his waking day was spent in seizure. His I.Q. was normal 104. If epilepsy is not controlled by medicine; a common used remedy is a brain legion. The surgeon will watch on EEG for the instigating neuron(s) and remove it. (The brain shifts its resonsibilities to other sections.) His surgery removed a certain part of his brain two large sections in the temporal lobe; and the hippocampus. He woke up just as he went in before. Only he couldn't remember anything new. (This sparked the idea that maybe brain regions are also a viable way to classify the memories we have.) - Milner A certain scientist came in and told H.M. to do the tower of hanoi problem. best you can do is about 34 moves. # Of moves. I\_____ I \____ I \_____ I \_____ I \_____ I \_____ I \____ I I 34 I________________________________________ 1 2 3 4 5 Trials Etc.... This was the case for H.M. he actually learned this task slightly faster than the average control human. He had no recollection of doing it however. Milner assumed certain brain sections were resonsible for certain memory. The type of memory Milner said H.M. still had was Procedural. The type H.M. had compromised was Declarative memory. R.B. was a normal 30 year old adult. Who came in for some minor surgery and had a stroke. His brain had loss of oxygen for five minutes. And caused only the largest neurons to be lost in the hypocampus. His waking symptoms mirror H.M.'s. Its hard to tell how test animals are handling memory becuase you can't obviously talk to them.... Animals are very good at organizing memory by spatial reasoning; memory. - Mapping Men are better at mapping. Women are better (within their sex) during some phases of their menstrual cycle. Where things are depends on orientation. Reference points. Frameworks. WE take an animal and devise a simple task to test their memory. - 8 Arm Maze - Each of the arms on this maze are encased in glass so the rat doesn't fall off or anything. Slightly food deprive a rat and place some at the X. You will teach the rat 7 different routes if you make sure you rotate the rat around different starting points on the maze. This is spatial. The rat would be using different spatial cues to find out where the food is. If you were to always put the food two arms to the right. This would not be spatial memory. \ I /X this is where the food is. \ I / \ I / \ I / \I/ -----------I----------- /I\ / I \ / I \ / I \ / I \ So we legion the hypocampus in a different group of animals and teach them the same task. They learn it much much slower. If you teach the legioned animals the non spatial task they learn it much much faster than the control animals. If the animals are trained on this...and then enebriated they act completely like the legioned animals.