• Learning is the process of acquiring representations of new information
• while memory refers to the persistence of that information in a state that can be revealed at a later time
• Learning is a set of processes initiated by experience
• Memory is a product of that process.

they are theoretical constructs because you cannot directly observe them. the fact that you learned and remembered (say for an exam you did well on) is inferred from your test performance and the professor's knowledge that you studied

Neurobiologists are motivated by the belief that memory traces have a physical basis in the brain.

Unlike the psychological approach that just studies the effects of experiences on their behavior, the neurobiological approach requires methods for determining the regions of the brain that make up the brain systems supporting memory, determining how synpases that are potential storage mechanisms are altered by experience and manipulating and measuring molecules in neurons that support memory. it combined the behavioral methods of psychology with methods from anatomy, electrophysiology, pharmacology, biochemistry and genetics.

at each level of the brain system, synapses and molecules, you manipulate an aspect of brain function and measure it. (do it at every level)

Psychological approach: the general goal of psychology is to derive a set of empirical principles that describe how variation in experience influences behavior. Also to provide a theoretical account that can explain the observed facts. A single methodology is used to collect the data and to test the theory. They do not directly manipulate or measure brain function. Operates on a single level of analysis. they study only the relationship between experience and behavior.

Neurobiological approach: the goal of neurobiology is to relate the basic facts of learning and memory to events happening in the brain. This is a Multi level approach. It is interdisciplinary also involving, behavioral methods of psychology with methods of anatomy, electrophysiology, pharmacology, biochemistry and genetics. In addition to using the behavioral methods of psychology that reveal how task variables such as trial spacing and repetition influence learning and retention, the neurobiological approach requires methods for
•    Determining the regions of the brain that make up the brain system supporting the memory •    Determining how synapses that are potential storage mechanisms are altered by experience •    Manipulating and measuring molecules in neurons that ultimately support the memory

Ebbinghaus

• developed the first scientific methods for assessing the acquisition and retention of a controlled experience
• wanted to study "pure" memory which required a methodology that could seperate what the subject already had learned from what the subject is now being asked to remember
• invented nonsense syllables: meaningless words
• documented the first forgetting curve which showed that most forgetting occurs within the first hour after that is slows down and levels off
• he found that as retention time increases, % recall decreases

Ribot

• he looked at how memory processes degrade in the face of disease- called this the dissolution of memory
• he had an idea that there is an orderly fashion to memory loss
• first you lose your most recent memories, next you lose your personal memories, next you lose your habit memories and lastly you lose your emotional memories
• this showed early thought that the brain is not a unitary system and that it was probably composed of many systems that capture various aspects of experience
• Ribot's law:proposed that old memories are more resistant to disease/disruption than new memories

Korsakoff

• He described the syndrome produced by alcohol now called Korsakoff’s Syndrome. 
  
• It is the syndrome now characterized by anterograde amnesia or the inability to acquire new memories. 
  
• He had two ideas as to why this occurred
• one idea was that the pathology impaired the physiological processes needed to establish and retain the memory
  
• second idea was that the pathology in some way weakened the associative network that contained the memory. 
  
• During the late stages there is also retrograde amnesia or the loss of memories acquired before the onset of the disease.

William James

• Proposed that memories emerge in stages.
  
• An after image is supported by a very short-lasting trace
• then replaced by the primary memory that also decays (here memory traces supporting the memory are in a position to influence your behavior) 
  
• Secondary memory is viewed as the reservoir of enduring memory trace that with an appropriate retrieval cue can be recalled.
  
• When retrieving LTM it goes back to the after image or active state.
• believed that as your gain experience things happen in the brain that change the status of the memory trace.

Ramon Y Cajal

• spanish neuroanatomist
• formulated the neuron doctrine: the idea that the brain is made up of discrete cells called nerve cells, each delimited by an external membrane
• discovered that neurons are truly independent genetically derived units that are composed of a cell body (soma), dendrites and a single axon
• he figured out the logic of the brain wiring diagram. he said axons can travel long or short distances but they are always terminated at specific locations among fields of dendrites
• also discovered what was later coined the synapse by Sherrington: axons ending wwere contiguous with dendrites but not continuous (fused) with them.
  
• also came up with the synaptic-plasticity hypothesis:  the idea hat the strength of a synaptic connection can be modified by experience
• he believed that the plastic property of the synapses could provide a means by which experience could produce the persistent changes in the brain needed to support memories
  

Ivan Pavlov

• developed the fundemental paradigm for studying associative learning and memory in animals
• the essence of the methodology of Classical (Pavlovian) conditioning is such that a neutral stimulus (CS) was paired with a biologically significant event (US). the US causes the UR (unconditioned response- happens automatically when presented with the stimulus)
• several pairings of the CS and US lead to the CR (conditioned respononse)
• the ability of the CS to evoke the CR is believed to be the result of the brain associating the occurance of the CS and US
• his experiment proved that behavior can be modified because 2 previously unrelated events can become associated together
  

Thorndike

• developed the first methodology for studying how we learn about the consequences of our actions
• this methodology is called instrumental conditioning or thorndikian conditioning
• proposed the law of effect: the correct behavior was learned because the consequences of successful outcome (a satisfying state) strengthened connections between the stimulus and the correct response and the consequence of unsuccessful responses (annoying state) weaken the competing and wrong stimulus- response connections

Memories may be produced in stages. What does this mean?

• this means that different areas of the brain must be responsible for holding different types of memory whether is it a recent memory, personal memory, a habit or skill, or emotional memory.
• this had implications that the brain has different systems for recording different aspects of your experiences (you can take 1 part away and still use the others)
• this showed early thought that the brain is not a unitary memory system it is probably composed of many systems that capture various aspects of experience

Ribot made 2 important contributions to memory research, what are they?

1. proposed that during diseases of the brain, memories dissapear in an orderly fashion: called it the dissolution of memory
2. Ribot's law: proposed that old memories are more resistent to disease/ disruption than new memories

According to William James, memories are laid down in a succession of traces. What are they?

• a sequence of processes initiated by an experience that beings with a breifly lasting sensation he called after images
• next stage is primary memory: persisting representation of the experience that forms part of the stream of consciousness
  
• last stage is secondary memory: contains the vast record of experiences that had recently recorded from the stream of consciousness but could be later retrieved or recollected

What is the relationship between stages of memory and and the state of memory trace?

• stages of memory refer to the after image vs. primary memory vs. secondary memory
• believed that as your gain experience things happen in the brain that change the status of the memory trace.
• there is a memory trace for each of these stages of memory and it varies in strength from one stage to another
• the after image has a trace that is very short in duration, but is initially very strong and accurate
• the primary memory's memory trace is less strong and fades
• the secondary memory's memory trace has the weakest trace, but it endures with proper retreival cues
  

What are the 2 major contributions to the field of learning and memory that Ramon Y Cajal is noted for?

1. the neuron doctrine: the idea that the brain is made up of discrete cells called nerve cells, each delimited by an external membrane
2. the synaptic- plasticisty hypothesis: the idea that the strength of a synaptic connection can be modified by experience

What is Korsakoff's syndome

a syndrome produced by alcohol that is charecterized by what we would now called anterograde amnesia- the inability to acquire new memories

during the late stages there is also retrograde amnesia- the loss of memories acquired before the onset of the disease

Memory loss can be the result of a storage or retrival failure. What does this mean?

• retreival failure: brain injury interfered with your ability to access information. You can potentially at a later time recover this memory. you have the memory stored you just cannot find it
• Storage failure: you can't ever recover memories lost due to this.

What is the difference between a memory that is in an active state and one that is in an inactive state?

• memory in an active state is memory that is currently being recalled or processed
• in an inactive state is memory that has been passed through and is either not being retrieved or not being processed into a long term memory

How does Pavlovian conditioning measure associative learning?

• the ability of the rhe conditioned stimulus (bell) to evoke the conditioned response (Salivation) is believed to be the result of the brain associating the occurance of the CS and US.
• the US evokes naturally an UC
• when you pair the US with the CS several times you get the CR because the brain associated the CS with the US

What does it mean to say that the content of experience matters to our memory systems?

• the brain has evolved neural systems that are specialized to capture and store the varied content generated by our experiences.
  
• we have different systems for different kinds of memories.
  
• this is normally represented by the term multiple memory system.

The neuron doctrine states:

1. the neuron is an anatomical unit- the fundemental structural and functional unit of the nervous system
2. the neuron is composed of 3 parts: cell body, dendrites, axon
3. neurons are discrete cells which are not continuous with other cells
4. the points of connection between neurons are called synapses
5. the neuron is a physiological unit. electical activity flows through the neuron in one direction (from dendrites to the axon, via the cell body)
6. the neuron is the developmental/ genetic unit of the nervous system
   

Synaptic- Plasticity Hypothesis

• Cajal's focal point was  to look at how  synaptic activity modifies synaptic strength
• hypothesized that the strength of a synaptic connection can be modified by experience
• experience can alter the ability of the presynaptic neuron to fire or depolarize the post synaptic terminal