Tuesday, November 7, 2023
Chapter 9: The Knowing Mind - Memory
PHY100
9.1 Introduction to Memory
- Memory is the ability to retain knowledge
- The evolution of memory allowed animals to use information from the past to
respond quickly to immediate challenges - an adaptive advantage
• The major drawback to building memory is the high-energy costs
- Plato and Aristotle used a wax tablet to describe memory - the memory is retained
by imprinting the perception or idea onto the wax; di erent types of wax lead to
di erent impressions, some quickly fade while some seem permanent
- Cognitive activity could be compared to the operations of a computer: data is
entered, stored in a system, and retrieved when needed
- Information processing is the ow of information through the nervous system,
involving perceptual systems, memory systems, and decision making and response
systems
- Memory is divided into three steps: encoding, storage, and retrieval
• Encoding is the process of acquiring information and transferring it into memory
- The sensory systems translate or transduce inputs and stimulations into action
potentials that can be processed by the nervous system, which can be encoded
in di erent forms in memory
• Storage is the retention of information and can last anywhere from seconds to
inde nitely
- Unlike computers, human memory does not generate exact records, instead bits
of information are stored that are later reconstructed into usable memories
• Retrieval is the recovery of stored information, but it’s not guaranteed
- The failure of memory retrieval is usually caused by either stress or interferences
1
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, 9.2 The Multistage Model of Memory
- Atkinson and Shi rin’s multistage model of memory proposes that data ow through
a series of separate stages of memory
9.2.1 Sensory Memory
- Sensory memory is the rst stage of the information processing model, it holds
enormous amounts of sensory data for brief periods that only last as long as the
neural activity produced by a sensation continues
- Sensory input is translated or transduced into several types of codes or
representations, which are mental models of a bit of information that exists even
when the information is no longer available
• Visual codes, or iconic memories, are used for the temporary storage of
information about visual images
• Haptic codes are used to process touch and other body senses
• Acoustic codes, or echoic memories, represent sounds and words, usually last
loner than visual codes
9.2.2 Short-Term Memory
- A tiny amount of information in the sensory memory movies to the next stage, short-
term memory (STM), for further processing
- Without additional processing, information in STM lasts for 30 seconds at most
• A classic study by Peterson and Peterson found that participants' ability to recall
letter triplets decreased as the time between presentation and recall increased
• If the information is repeated over and over, or rehearsal, it states in STM
inde nitely, so long as you don’s think about anything else
• Data in short-term memory are easily displaced by new, incoming bits of data
- STM is also characterized by severe limitations in capacity
• Memory capacities vary from individual to individual, and memory tasks appear
prominently in standardized tests of intelligence
- The brief duration and limited capacity of STM ensure that room is freed regularly for
incoming information and the content search process is e cient
2
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Chapter 9: The Knowing Mind - Memory
PHY100
9.1 Introduction to Memory
- Memory is the ability to retain knowledge
- The evolution of memory allowed animals to use information from the past to
respond quickly to immediate challenges - an adaptive advantage
• The major drawback to building memory is the high-energy costs
- Plato and Aristotle used a wax tablet to describe memory - the memory is retained
by imprinting the perception or idea onto the wax; di erent types of wax lead to
di erent impressions, some quickly fade while some seem permanent
- Cognitive activity could be compared to the operations of a computer: data is
entered, stored in a system, and retrieved when needed
- Information processing is the ow of information through the nervous system,
involving perceptual systems, memory systems, and decision making and response
systems
- Memory is divided into three steps: encoding, storage, and retrieval
• Encoding is the process of acquiring information and transferring it into memory
- The sensory systems translate or transduce inputs and stimulations into action
potentials that can be processed by the nervous system, which can be encoded
in di erent forms in memory
• Storage is the retention of information and can last anywhere from seconds to
inde nitely
- Unlike computers, human memory does not generate exact records, instead bits
of information are stored that are later reconstructed into usable memories
• Retrieval is the recovery of stored information, but it’s not guaranteed
- The failure of memory retrieval is usually caused by either stress or interferences
1
ff ff
fi fl ff
, 9.2 The Multistage Model of Memory
- Atkinson and Shi rin’s multistage model of memory proposes that data ow through
a series of separate stages of memory
9.2.1 Sensory Memory
- Sensory memory is the rst stage of the information processing model, it holds
enormous amounts of sensory data for brief periods that only last as long as the
neural activity produced by a sensation continues
- Sensory input is translated or transduced into several types of codes or
representations, which are mental models of a bit of information that exists even
when the information is no longer available
• Visual codes, or iconic memories, are used for the temporary storage of
information about visual images
• Haptic codes are used to process touch and other body senses
• Acoustic codes, or echoic memories, represent sounds and words, usually last
loner than visual codes
9.2.2 Short-Term Memory
- A tiny amount of information in the sensory memory movies to the next stage, short-
term memory (STM), for further processing
- Without additional processing, information in STM lasts for 30 seconds at most
• A classic study by Peterson and Peterson found that participants' ability to recall
letter triplets decreased as the time between presentation and recall increased
• If the information is repeated over and over, or rehearsal, it states in STM
inde nitely, so long as you don’s think about anything else
• Data in short-term memory are easily displaced by new, incoming bits of data
- STM is also characterized by severe limitations in capacity
• Memory capacities vary from individual to individual, and memory tasks appear
prominently in standardized tests of intelligence
- The brief duration and limited capacity of STM ensure that room is freed regularly for
incoming information and the content search process is e cient
2
fi ff fi ffi fl
