Attention and Memory

Attention and Memory 7 Eric Kandel – “Memories are Made of This” http://www.youtube.com/watch?v=K0cnyqzqgkQ&feature=related

Questions to Consider: • How Does Attention Determine What Is Remembered? • What Are the Basic Stages of Memory? • What Are the Different Long-Term Memory Systems? • How Is Information Organized in Long- Term Memory? • What Brain Processes Are Involved in Memory? • When Do People Forget? • How Are Memories Distorted? • How Can We Improve Learning and Memory?

I. How Does Attention Determine What Is Remembered? • Visual Attention Is Selective and Serial • Auditory Attention Allows Selective Listening • Selective Attention Can Operate at Multiple Stages of Processing

1. Visual Attention Is Selective and Serial • Visual attention operates through both automatic and effortful processes • We automatically and rapidly identify stimuli that differ in only one single feature (e.g., size, color, orientation) • Parallel processing • Searching for two features (e.g., red and large) happens slowly and serially

Parallel processing allows us to process information from different visual features at the same time by focusing on targets (here, the red objects) over distractors.

2. Auditory Attention Allows Selective Listening • We can attend to more than one message at a time but not well • Selective listening • We process some unattended information but in a weaker form than we process attended information

3. Selective Attention Can Operate at Multiple Stages of Processing • Filter Theory • Limited capacity for sensory information • Attention is a gate: important info in, irrelevant info out • Change blindness • We often miss large objects in our visual field when we are attending to something else • Although most people do not believe they can fail to see large objects right in front of them, numerous studies show this is the case

II. What Are the Basic Stages of Memory? • Sensory Memory Is Brief • Working Memory Is Active • Long-Term Memory Is Relatively Permanent

(a) The information processing model compares the working of memory to the actions of a computer. (b) The modal memory model serves as a useful framework for thinking about the basic stages of memory.

1. Sensory Memory Is Brief • Visual and auditory memories are maintained at the sensory memory stage long enough to ensure a continuous sensory experience

2. Working Memory Is Active • Immediate active memory is limited. • Working memory holds information for about 20– 30 seconds unless you make efforts to maintain information • Memory span • Chunking reduces information into meaningful units that are easier to remember.

3. Long-Term Memory Is Relatively Permanent • Long-term memory (LTM) is the potentially indefinite storage of all memories • Distinct from working memory in duration and capacity • Meaningful memories are stored in LTM in networklike structures

III. What Are the Different Long-Term Memory Systems? • Explicit Memory Involves Conscious Effort • Implicit Memory Occurs without Deliberate Effort • Prospective Memory Is Remembering to Do Something

III. What Are the Different Long-Term Memory Systems? • Memory is not a single process or brain system • Fundamental differences exist among episodic and semantic memory, explicit and implicit memory, and prospective memory

1. Explicit Memory Involves Conscious Effort • Explicit, declarative memories that we consciously remember include: • Episodic memory (personal events) • Semantic memory (knowledge)

2. Implicit Memory Occurs without Deliberate Effort • Implicit memory consists of memories about which we have no conscious knowledge • Procedural (motor) memories of how to do things automatically • Classical conditioning

3. Prospective Memory Is Remembering to Do Something • Prospective memory consists of remembering to do something at some future time • Has “costs” in terms of reducing attention and reducing working memory capacity

IV. How Is Information Organized in Long-Term Memory? • Long-Term Storage Is Based on Meaning • Schemas Provide an Organizational Framework • Information Is Stored in Association Networks • Retrieval Cues Provide Access to Long-Term Storage

1. Long-Term Storage Is Based on Meaning • Memory processes include encoding, storage, and retrieval • Memories are stored by meaning • Elaborative rehearsal involves encoding information in more meaningful ways and results in better memory than maintenance (repetition) rehearsal.

2. Schemas Provide an Organizational Framework • Schemas are structures in long-term memory that help us perceive, organize, process and use information • Cultural variations in schemas produce differences in what and how information is remembered • Can lead to biased encoding

3. Information Is Stored in Association Networks • Networks of associations • Formed by nodes of information • Nodes are linked together • Spreading activation

In this semantic network, similar concepts are connected through their associations.

4. Retrieval Cues Provide Access to Long-Term Storage • A retrieval cue is anything that helps access the right information stored in long-term memory • Easier to recognize than recall information • According to the encoding specificity principle, any stimulus encoded along with an experience can later trigger the memory of the experience • Memory’s context also activated

V. What Brain Processes Are Involved in Memory? • There Has Been Intensive Effort to Identify Memory’s Physical Location • The Medial Temporal Lobes Are Important for Consolidation of Declarative Memories • The Frontal Lobes Are Involved in Many Aspects of Memory • Neurochemistry Underlies Memory

1. There Has Been Intensive Effort to Identify Memory’s Physical Location • Research during the past thirty years has demonstrated that memories are encoded in distributed networks of neurons in relatively specific brain regions • Karl Lashley • Unable to locate a specific site of memory storage (engram) • Equipotentiality (not quite right)

1. There Has Been Intensive Effort to Identify Memory’s Physical Location • Memories are stored in multiple regions of the brain and linked through memory circuits • Different regions responsible for storing different information • Research has revealed that a number of specific brain regions contribute to learning and memory.

2. Medial Temporal Lobes: Important for Consolidation of Declarative Memories • Immediate memories become lasting memories through consolidation • Consolidation involves changes in neural connections, short-term/workinglong-term • Reconsolidation: memories recalled and restored • Vulnerable to changes or forgetting • The hippocampus, a structure in the medial temporal lobe, is important for declarative memories

Four horizontally sliced brain images acquired using magnetic resonance imaging indicate that regions of the sensory cortex are reactivated when we remember sensory-specific information.

2. Medial Temporal Lobes: Important for Consolidation of Declarative Memories • Spatial memory: • Memory for the physical environment • Location of objects, direction, cognitive maps • Place cells in the hippocampus aid spatial memory • In lab, place cells fire only when a rat returns to a specific location, not in a new environment

3. The Frontal Lobes Are Involved in Many Aspects of Memory • Extensive neural networks connect the frontal lobes with other memory regions of the brain • Brain imaging studies show that the frontal lobes are crucial for encoding • Activation of neurons in the frontal lobe is associated with deeper meaning

3. The Frontal Lobes Are Involved in Many Aspects of Memory • The frontal lobe may also play a role in working memory • Patients with damage to frontal areas, human infants, and monkeys with frontal lesions all have difficulty with tasks associated with working memory

4. Neurochemistry Underlies Memory • A group of neurochemicals modulates the storage of memories (memory modulators) • Epinephrine enhances memory • Excreted from adrenal glands when an animal is excited or afraid

4. Neurochemistry Underlies Memory • The Amygdala: • Probably responsible for memory modulation through activity in its norepinephrine receptors • Amygdala is activated during emotional memory

Attention and Memory