Research Topics in Memory

The Survival Processing EffectRemembered AffordancesProspective Memory Retrieval

The Process of Remembering

Encoding

Delay

Retrieval

The Survival Processing EffectAn evolutionary origin of our memory

system Nairne, Thompson, & Pandeirada (2007)

Survival processing of items was shown to enhance subsequent recall and recognition

The effect is robust even when compared to good mnemonic processing strategies e.g., pleasantness

Nairne & Pandeirada (2010) Ancestral survival scenarios were shown to

enhance recall more than modern survival scenarios

The Current StudyTwo experiments and three

hypotheses

Stem completion task (Experiment 1): More likely to complete letter strings with words they studied in the survival scenario

Category production task (Experiment 2): Produce a higher proportion of studied words processed in a survival scenario

Design Between-subjects independent variable

Rating scenario: Survival, moving, and pleasantness

Dependent variable Proportion of rated words retreived

Experiment 1 Procedure

Experiment 1 Results

Results Re-examined

Experiment 2 Procedure

Experiment 2 Results

ConclusionExperiment 1

High baseline in moving scenario drove memory score differences

Experiment 2No survival effect on the

proportion of studied items retrieved

Discussion

How would you interpret these results?

What do these results mean from an evolutionary standpoint?

Could a problem with our method account for the lack of results?

Remembered Affordances

Affordances

Can I reach?

Affordances Possibilities to behave Action-scaled

Depend on perceiver-environment fit Change over short and long timescales Nestedness

Require the performance of prerequisite behaviors

Involve expected changes in action capabilities Functional Equivalence

Two objects change affordances in the same way regardless of the specific means

Remembered Affordances

Figure reprinted from Boschker et al. (2002)

Research Questions Do people’s reaching estimates change

when the means for performing the reach are absent instead of present?

If two different objects bring about the same change in action capability, is the perception and memory of these objects’ affordances the same (functionally equivalent)?

Experiment 1: Procedure

Can I reachWith arm ?

Can I reach With stick?

Can I reach With Stick?

Can I reach With stick?

Stick_Present Stick_Present_2Hand Stick_Absent

Figure 1. Mean perceived maximum reaching height in the four conditions Experiment 1. Error bars indicate standard error.

Results1.Actual Maximum Reaching Height: Hand < Stick 

2. Perceived Maximum Reaching Height: Hand < Stick Present = Stick Absent

3. Ratio of perceived/actual reaching height:Hand = Stick Present = Stick Absent

Experiment 2: Procedure

Can I reachWith arm ?

Can I reach With step?

Can I reach With step?

Can I reach With step?

Step_Present Step_Present_2Floor Step_Absent

Figure 2. Mean perceived maximum reaching height in the four conditions Experiment 2. Error bars indicate standard error.

Results1.Actual Maximum Reaching Height: Floor < Step 

2. Perceived Maximum Reaching Height: Floor < Step Present = Step Absent

3. Ratio of perceived/actual reaching height:Floor = Stick Present = Stick Absent

Experiment 3: Procedure

Can I reach With stick?

Can I reach With step?

Can I reach With arm? Can I reach

With stick?

Can I reach With step?

Step_Present Floor/Arm Step_AbsentStick_AbsentStick_Present

Figure 3. Mean perceived maximum reaching height in the five conditions Experiment 3. Error bars indicate standard error.

Hypotheses1. Actual Maximum Reaching Height: Floor/Hand < Stick = Step 

2. Perceived Maximum Reaching Height:  Floor/Hand < Stick Present = Stick AbsentFloor/Hand < Step Present = Step Absent

3. No difference in Ratio of Perceived to Actual Maximum Reaching Height in any conditions

4. Functional Equivalence:Stick Present = Step Present; Stick Absent = Step Absent

Conclusions Experiments 1 and 2

Perception of reaching ability was action scaled when objects were present and absent

Experiment 3 Replicated first two experiments Objects that changed max reaching

height by the same amount were perceived and remembered to be functionally equivalent

Discussion

What do these results mean for remembered affordances?

What else might this apply to (e.g. other affordances)?

What could this mean for memory in general?

Prospective Memory Retrieval Prospective memory: PM Memory for future intentions Time-based

Completing a future intention after a pre-specified interval e.g., Going to class

Event-based Completing an intention after the presentation of a

pre-specified cue e.g., Remembering to turn off the lights at your

house before you leave

Standard PM Paradigm

Ongoing task Lexical decision task Word/picture rating task Category judgment taskEmbedded PM task Category member Word/picture Palindromes

Common Dependent Measures Accuracy

The proportion of correct PM actions committed Often used to evaluate the effects of independent

variables on PM performance

Ongoing Task Cost/Interference The difference in RTs of ongoing task responses

with and without an embedded PM task The relative cost of embedding a PM task within an

ongoing task Used as a measure of participants’ degree of

allocated attention to the PM task

Retrieval: The Attention DebateIs attention necessary for completing PM

actions? Preparatory Attention and Memory model: PAM

Attention to the PM task is necessary for completing intended actions (Smith et al., 2007)

Multiprocess model: MP Multiple strategies may be employed to execute

intended actions Spontaneous retrieval

My thesis topic! Preparatory attentional processes

Spontaneous Retrieval

Discrepancy Attribution Hypothesis (Whittlesea and Williams 2001a. 2001b.) Gauging familiarity based on a discrepancy

in processing

Probabilistic Learning Organisms are good at abstracting

environmental regularities (Brunswick, 1943)

Processing regular environments creates expectancies for similar contexts

Violations of these expectancies can create processing perturbations

This process might be useful as a discrepancy-plus-search mechanism

Research Questions Could the presentation of several words of

a single category in an ongoing task prime the expectation of a category member?

Might the violation of this expectation support a discrepancy-plus-search mechanism?

How much category priming must occur before PM is affected?

What is the role of attention in this paradigm?

Design

Between-Subjects Factors Instruction

PM: PM instructions for the experimental block

Recall: Recall instructions with the same items used for the PM task Allows us to explore the role of

attention in the experimental block Similar RTs for two conditions = less

attentional resources allocated

DesignBetween-Subjects Factors

Stimulus Discrepancy Congruent: Items in the ongoing task from the same

category as the PM cues Discrepant: Items in the ongoing task from a different

category than the PM cues

Category Priming Proportion Proportion of items from the dominant category in the

priming and experimental blocks: .25, .5, .75 Allows me to gauge the point at which stimulus

discrepancy alters PM accuracy

DesignWithin-Subjects Factor

Block1. Baseline block: Stimuli from random categories

Used to compare RTs to other blocks to asses attentional allocation

2. Priming block: Proportions of category exemplars depending on category priming proportion condition Used to prime categories Used as a distracter task to discourage attention to PM task

3. Experimental block: Same as priming block with the introduction of a PM task depending on experimental block condition Used to asses the stimulus discrepancy manipulation

Procedure

12 Between-Subjects Conditions

InstructionStimulus

Discrepancy

Category Priming

Proportion

Accuracy Results

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0.25 0.5 0.75

Proportion Condition

Prop

ortio

n of

Cor

rect

PM

Res

pons

es

discrepant

congruent

RT Results

0

50

100

150

200

250

300

350

400

450

PM Recall

Instruction Condition

Bloc

k 1

- Blo

ck 3

RT

Diff

eren

ce

discrepant

congruent

Conclusions

Discrepant ongoing task items increased PM accuracy

.25 items from a category may be sufficient for spontaneous retrieval

Discussion

How do these results relate back to the research questions?

Describe the process that led to the accuracy results.

What do these results mean for the retrieval debate?