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The awareness of novelty for strangely familiar words: a laboratory analogue of the déjà vu experience.

Urquhart JA, O'Connor AR - PeerJ (2014)

Bottom Line: We found that déjà vu reports were most frequent for high novelty critical words (∼25%), with low novelty critical words yielding only baseline levels of déjà vu report frequency (∼10%).There was no significant variation in déjà vu report frequency according to familiarity strength.We discuss theoretical and methodological considerations relevant to further development of this procedure and propose that verifiable novelty is an important component of both naturalistic and experimental analogues of déjà vu.

View Article: PubMed Central - HTML - PubMed

Affiliation: School of Psychology & Neuroscience, University of St Andrews , UK.

ABSTRACT
Déjà vu is a nebulous memory experience defined by a clash between evaluations of familiarity and novelty for the same stimulus. We sought to generate it in the laboratory by pairing a DRM recognition task, which generates erroneous familiarity for critical words, with a monitoring task by which participants realise that some of these erroneously familiar words are in fact novel. We tested 30 participants in an experiment in which we varied both participant awareness of stimulus novelty and erroneous familiarity strength. We found that déjà vu reports were most frequent for high novelty critical words (∼25%), with low novelty critical words yielding only baseline levels of déjà vu report frequency (∼10%). There was no significant variation in déjà vu report frequency according to familiarity strength. Discursive accounts of the experimentally-generated déjà vu experience suggest that aspects of the naturalistic déjà vu experience were captured by this analogue, but that the analogue was also limited in its focus and prone to influence by demand characteristics. We discuss theoretical and methodological considerations relevant to further development of this procedure and propose that verifiable novelty is an important component of both naturalistic and experimental analogues of déjà vu.

No MeSH data available.


Related in: MedlinePlus

Schematic of study and test lists.A possible study and test list for a high familiarity DRM list with critical lure ‘sleep’. At the start of the study list, participants were presented with a question reminding them to monitor the study list for words beginning with a character string. The character string remained onscreen throughout the study list. In this case, the high novelty condition string was ‘SLE’ and the low novelty condition string was ‘B’. Participants were then presented with 12 words semantically related to the unpresented critical lure, each word presented at 3 s intervals. At the end of the study list, participants indicated the number of words presented which began with the character string. In high novelty conditions, the correct answer was always ‘0’, in low novelty conditions the correct answer always greater than 0. Six study lists were presented in each study phase before the test phase was initiated. At the start of each test list, participants were reminded of the previously monitored string and the number of words they reported at study beginning with this string. The reminder remained onscreen throughout the eight-word test list. For each test trial, participants first indicated whether the word had been presented at study (old) or not (new) and then indicated their confidence in this decision. Throughout both of these self-paced decisions, participants could toggle their déjà vu response from ‘none’ through ‘low’, ‘medium’ and ‘high’. Once participants made a confidence decision the next test trial was initiated. In the schematic, different word conditions are shown bounded by different coloured boxes and the reminder information is omitted from test words 2–8 for the sake of clarity. In the experiment there was no differentiation of stimulus type visible to participants. The six test lists corresponding to the six study lists from the preceding study phase were presented in the test phase. Over the entire experiment, there were four study-test blocks.
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fig-1: Schematic of study and test lists.A possible study and test list for a high familiarity DRM list with critical lure ‘sleep’. At the start of the study list, participants were presented with a question reminding them to monitor the study list for words beginning with a character string. The character string remained onscreen throughout the study list. In this case, the high novelty condition string was ‘SLE’ and the low novelty condition string was ‘B’. Participants were then presented with 12 words semantically related to the unpresented critical lure, each word presented at 3 s intervals. At the end of the study list, participants indicated the number of words presented which began with the character string. In high novelty conditions, the correct answer was always ‘0’, in low novelty conditions the correct answer always greater than 0. Six study lists were presented in each study phase before the test phase was initiated. At the start of each test list, participants were reminded of the previously monitored string and the number of words they reported at study beginning with this string. The reminder remained onscreen throughout the eight-word test list. For each test trial, participants first indicated whether the word had been presented at study (old) or not (new) and then indicated their confidence in this decision. Throughout both of these self-paced decisions, participants could toggle their déjà vu response from ‘none’ through ‘low’, ‘medium’ and ‘high’. Once participants made a confidence decision the next test trial was initiated. In the schematic, different word conditions are shown bounded by different coloured boxes and the reminder information is omitted from test words 2–8 for the sake of clarity. In the experiment there was no differentiation of stimulus type visible to participants. The six test lists corresponding to the six study lists from the preceding study phase were presented in the test phase. Over the entire experiment, there were four study-test blocks.

Mentions: The key omission in the déjà vu generation procedures described above is the provision of information allowing the participant to make an evaluation of unfamiliarity or novelty to clash with the experimentally-generated familiarity. In these procedures, there was no objective standard by which participants could verify that the stimuli provoking familiarity had in fact not previously been encountered. With a view to generating a more complete laboratory analogue of naturalistic déjà vu, we developed a procedure during which some stimuli elicit both subjective familiarity and an awareness of novelty. This procedure builds on the DRM recognition task (Deese, 1959; Roediger & McDermott, 1995) in which participants study a series of words (e.g., rest, bed and blanket) which are all semantically linked to an unpresented word (sleep). This unpresented word, referred to as the critical lure, typically yields illusory recognition when it is presented at test—the critical lure generates a sensation of subjective familiarity. Our procedure pairs the DRM task with an additional task in which participants monitor studied stimuli for a feature present only in the critical lure (e.g., the starting letters ‘sle’). When participants become aware of the absence of that feature from the study list words, they also become aware that the critical lure must in fact be novel (see Fig. 1). Thus in critical lures, subjective familiarity clashes with an objective awareness of novelty, satisfying the definition of déjà vu.


The awareness of novelty for strangely familiar words: a laboratory analogue of the déjà vu experience.

Urquhart JA, O'Connor AR - PeerJ (2014)

Schematic of study and test lists.A possible study and test list for a high familiarity DRM list with critical lure ‘sleep’. At the start of the study list, participants were presented with a question reminding them to monitor the study list for words beginning with a character string. The character string remained onscreen throughout the study list. In this case, the high novelty condition string was ‘SLE’ and the low novelty condition string was ‘B’. Participants were then presented with 12 words semantically related to the unpresented critical lure, each word presented at 3 s intervals. At the end of the study list, participants indicated the number of words presented which began with the character string. In high novelty conditions, the correct answer was always ‘0’, in low novelty conditions the correct answer always greater than 0. Six study lists were presented in each study phase before the test phase was initiated. At the start of each test list, participants were reminded of the previously monitored string and the number of words they reported at study beginning with this string. The reminder remained onscreen throughout the eight-word test list. For each test trial, participants first indicated whether the word had been presented at study (old) or not (new) and then indicated their confidence in this decision. Throughout both of these self-paced decisions, participants could toggle their déjà vu response from ‘none’ through ‘low’, ‘medium’ and ‘high’. Once participants made a confidence decision the next test trial was initiated. In the schematic, different word conditions are shown bounded by different coloured boxes and the reminder information is omitted from test words 2–8 for the sake of clarity. In the experiment there was no differentiation of stimulus type visible to participants. The six test lists corresponding to the six study lists from the preceding study phase were presented in the test phase. Over the entire experiment, there were four study-test blocks.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
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fig-1: Schematic of study and test lists.A possible study and test list for a high familiarity DRM list with critical lure ‘sleep’. At the start of the study list, participants were presented with a question reminding them to monitor the study list for words beginning with a character string. The character string remained onscreen throughout the study list. In this case, the high novelty condition string was ‘SLE’ and the low novelty condition string was ‘B’. Participants were then presented with 12 words semantically related to the unpresented critical lure, each word presented at 3 s intervals. At the end of the study list, participants indicated the number of words presented which began with the character string. In high novelty conditions, the correct answer was always ‘0’, in low novelty conditions the correct answer always greater than 0. Six study lists were presented in each study phase before the test phase was initiated. At the start of each test list, participants were reminded of the previously monitored string and the number of words they reported at study beginning with this string. The reminder remained onscreen throughout the eight-word test list. For each test trial, participants first indicated whether the word had been presented at study (old) or not (new) and then indicated their confidence in this decision. Throughout both of these self-paced decisions, participants could toggle their déjà vu response from ‘none’ through ‘low’, ‘medium’ and ‘high’. Once participants made a confidence decision the next test trial was initiated. In the schematic, different word conditions are shown bounded by different coloured boxes and the reminder information is omitted from test words 2–8 for the sake of clarity. In the experiment there was no differentiation of stimulus type visible to participants. The six test lists corresponding to the six study lists from the preceding study phase were presented in the test phase. Over the entire experiment, there were four study-test blocks.
Mentions: The key omission in the déjà vu generation procedures described above is the provision of information allowing the participant to make an evaluation of unfamiliarity or novelty to clash with the experimentally-generated familiarity. In these procedures, there was no objective standard by which participants could verify that the stimuli provoking familiarity had in fact not previously been encountered. With a view to generating a more complete laboratory analogue of naturalistic déjà vu, we developed a procedure during which some stimuli elicit both subjective familiarity and an awareness of novelty. This procedure builds on the DRM recognition task (Deese, 1959; Roediger & McDermott, 1995) in which participants study a series of words (e.g., rest, bed and blanket) which are all semantically linked to an unpresented word (sleep). This unpresented word, referred to as the critical lure, typically yields illusory recognition when it is presented at test—the critical lure generates a sensation of subjective familiarity. Our procedure pairs the DRM task with an additional task in which participants monitor studied stimuli for a feature present only in the critical lure (e.g., the starting letters ‘sle’). When participants become aware of the absence of that feature from the study list words, they also become aware that the critical lure must in fact be novel (see Fig. 1). Thus in critical lures, subjective familiarity clashes with an objective awareness of novelty, satisfying the definition of déjà vu.

Bottom Line: We found that déjà vu reports were most frequent for high novelty critical words (∼25%), with low novelty critical words yielding only baseline levels of déjà vu report frequency (∼10%).There was no significant variation in déjà vu report frequency according to familiarity strength.We discuss theoretical and methodological considerations relevant to further development of this procedure and propose that verifiable novelty is an important component of both naturalistic and experimental analogues of déjà vu.

View Article: PubMed Central - HTML - PubMed

Affiliation: School of Psychology & Neuroscience, University of St Andrews , UK.

ABSTRACT
Déjà vu is a nebulous memory experience defined by a clash between evaluations of familiarity and novelty for the same stimulus. We sought to generate it in the laboratory by pairing a DRM recognition task, which generates erroneous familiarity for critical words, with a monitoring task by which participants realise that some of these erroneously familiar words are in fact novel. We tested 30 participants in an experiment in which we varied both participant awareness of stimulus novelty and erroneous familiarity strength. We found that déjà vu reports were most frequent for high novelty critical words (∼25%), with low novelty critical words yielding only baseline levels of déjà vu report frequency (∼10%). There was no significant variation in déjà vu report frequency according to familiarity strength. Discursive accounts of the experimentally-generated déjà vu experience suggest that aspects of the naturalistic déjà vu experience were captured by this analogue, but that the analogue was also limited in its focus and prone to influence by demand characteristics. We discuss theoretical and methodological considerations relevant to further development of this procedure and propose that verifiable novelty is an important component of both naturalistic and experimental analogues of déjà vu.

No MeSH data available.


Related in: MedlinePlus