Alfonso Pitarque

Familiarity-based recognition in the young, healthy elderly, mild cognitive impaired and Alzheimer's patients.

This study investigates the possible existence of deficits in familiarity in five samples of participants spanning a broad range of ages and cognitive states. Five groups of 16 participants with a diagnosis of multi-domain cognitive impairment with a slight or no deficit in memory, 16 multi-domain amnestic, and 16 Alzheimers disease patients were compared in a recognition test with equivalent samples of old and young healthy participants. In one of the tests, participants studied words extracted from a restricted set of letters of the alphabet that were later mixed with new words from a different set. The unconscious use of the fluency produced by the repeated use of the set of letters was compared with a condition in which the same letter set did not play a role. Results indicated that amnestic mild cognitive impaired and Alzheimers patients were unable to use letter fluency to improve recognition. However, young and old controls did not differ among themselves, whereas the multi-domain sample, whose memory performance was almost at the same level as that of controls showed slight levels of deficit in familiarity in the forced choice test but not in the recognition test. These results contrast sharply with those reported by Westerberg et al. [Westerberg, C. E., Paller, K. E., Holdstock, J. S., Mayes, A. R., & Reber, p. J. (2006). When memory does not fail: Familiarity-based recognition in mild cognitive impairment and Alzheimers disease. Neuropsychology, 20, 193-205] and Anderson et al. [Anderson, N. D., Ebert, P. L., Jennings, J. M., Grady, C. L., Cabeza, R., & Graham, S. J. (2008). Recollection- and familiarity-based memory in healthy aging and amnestic mild cognitive impairment. Neuropsychology, 22, 177-187], who concluded that there were no deficits in familiarity in these types of pre-dementia and dementia patients.

Recognition memory deficits in mild cognitive impairment

ABSTRACT There is no agreement on the pattern of recognition memory deficits characteristic of patients diagnosed with mild cognitive impairment (MCI). Whereas lower performance in recollection is the hallmark of MCI, there is a strong controversy about possible deficits in familiarity estimates when using recognition memory tasks. The aim of this research is to shed light on the pattern of responding in recollection and familiarity in MCI. Five groups of participants were tested. The main participant samples were those formed by two MCI groups differing in age and an Alzheimers disease group (AD), which were compared with two control groups. Whereas one of the control groups served to assess the performance of the MCI and AD people, the other one, composed of young healthy participants, served the purpose of evaluating the adequacy of the experimental tasks used in the evaluation of the different components of recognition memory. We used an associative recognition task as a direct index of recollection and a choice task on a pair of stimuli, one of which was perceptually similar to those studied in the associative recognition phase, as an index of familiarity. Our results indicate that recollection decreases with age and neurological status, and familiarity remains stable in the elderly control sample but it is deficient in MCI. This research shows that a unique encoding situation generated deficits in recollective and familiarity mechanisms in mild cognitive impaired individuals, providing evidence for the existence of deficits in both retrieval processes in recognition memory in a MCI stage.

Recognition by Familiarity Is Preserved In Parkinson's Without Dementia and Lewy-Body Disease

OBJECTIVE The retrieval deficit hypothesis states that the lack of deficit in recognition often observed in patients with Parkinsons disease is because of the low retrieval requirements of the task, given that these patients have retrieval and not encoding deficits. To test this hypothesis we investigated recognition memory by familiarity in Parkinsons patients and in patients with Lewy Bodies disease and Parkinson with dementia. METHOD We analyzed to what extent the experimental groups were able to recognize by familiarity in a typical yes/no recognition memory task. The experimental groups were patients with early nondemented Parkinsons disease, advanced nondemented Parkinsons disease, demented Parkinsons patients, and patients with dementia with Lewy Bodies. We compared their performance with a group of young and another group of old healthy participants. The estimation of familiarity was made by analyzing recognition of word targets and distractors consisting of combinations of different letters in comparison with a condition in which targets and distractors were composed of similar letters, even though subjects were unaware of the independent variable. RESULTS The results indicate that familiarity was used at the same level by controls, patients with early Parkinsons disease and patients with dementia with Lewy Bodies. Although late Parkinson patients also used familiarity, its effect was only marginally significant. Patients with Parkinsons disease and dementia were not capable of using familiarity in recognition memory. CONCLUSIONS Our results support the retrieval deficit hypothesis as Parkinsons patients without dementia show no deficit in a situation in which the retrieval requirements are minimal.

Explorations of familiarity produced by words with specific combinations of letters

We explore familiarity-based recognition using a paradigm devised by Parkin et al. (2001). The task consists of the creation of two lists of words written with one of two different subsets of letters of the alphabet. We manipulated study time (50, 100, 200, 500 ms per word) of words with different letter probabilistic structure to those originally used by Parkin et al. Letter-based familiarity responding was robust and present even at rates producing otherwise chance performance. A second experiment and structural equation modelling led us to interpret the results from the point of view of a theory that takes into account the processing of similarities and differences (Hunt & MacDaniel, 1993). Finally, our data indicate that the experimental procedure devised by Parkin et al. is an excellent tool with which to study familiarity, once the structure of probabilities of individual letters is considered as the key factor in inducing the effect.

Repetition increases false recollection in older people

Aging is accompanied by an increase in false alarms on recognition tasks, and these false alarms increase with repetition in older people (but not in young people). Traditionally, this increase was thought to be due to a greater use of familiarity in older people, but it was recently pointed out that false alarms also have a clear recollection component in these people. The main objective of our study is to analyze whether the expected increase in the rate of false alarms in older people due to stimulus repetition is produced by an inadequate use of familiarity, recollection, or both processes. To do so, we carried out an associative recognition experiment using pairs of words and pairs of images (faces associated with everyday contexts), in which we analyzed whether the repetition of some of the pairs increases the rate of false alarms in older people (compared to what was found in a sample of young people), and whether this increase is due to familiarity or recollection (using a remember-know paradigm). Our results show that the increase in false alarms in older people due to repetition is produced by false recollection, calling into question both dual and single-process models of recognition. Also, older people falsely recollect details of never studied stimuli, a clear case of perceptual illusions. These results are better explained in terms of source-monitoring errors, mediated by peoples retrieval expectations.

Effect of retention interval on the simultaneous cognate-noncognate and remember-know mirror effects.

Recognition memory for Spanish-Catalan cognate and noncognate words was tested at retention intervals of 30 minutes, 3 days, and 7 days using a remember/know response procedure. We observed a clear mirror effect for the cognate-noncognate stimulus class and a remember-know response categorisation at the immediate retention interval. However, the cognate and noncognate mirror was still observed at 3 and 7 days, whereas the remember-know mirror disappeared at both retention intervals. Also, we ran a repeated testing condition to be able to carry out a sequential item analysis and observe the fate of the original remember and know responses 3 or 7 days later. The analysis supported the idea that there was a loss of contextual information that was at the root of the disappearance of the remember-know mirror effect. These results provide support to the idea that it is the imbalance between recollection and familiarity that is the most likely cause of the mirror effect.

The effects of healthy aging, amnestic mild cognitive impairment, and Alzheimer's disease on recollection, familiarity and false recognition, estimated by an associative process-dissociation recognition procedure.

Given the uneven experimental results in the literature regarding whether or not familiarity declines with healthy aging and cognitive impairment, we compare four samples (healthy young people, healthy older people, older people with amnestic mild cognitive impairment - aMCI -, and older people with Alzheimers disease - AD -) on an associative recognition task, which, following the logic of the process-dissociation procedure, allowed us to obtain corrected estimates of recollection, familiarity and false recognition. The results show that familiarity does not decline with healthy aging, but it does with cognitive impairment, whereas false recognition increases with healthy aging, but declines significantly with cognitive impairment. These results support the idea that the deficits detected in recollection, familiarity, or false recognition in older people could be used as early prodromal markers of cognitive impairment.

Differences in familiarity according to the cognitive reserve of healthy elderly people / Diferencias en familiaridad en función de la reserva cognitiva en ancianos sanos

Abstract This study examines the relationship between cognitive reserve and familiarity processes in recognition memory. We hypothesize that people with high cognitive reserve are able to better compensate in alternative information retrieval processes. Forty-five participants, divided into high and low cognitive reserve groups, conducted a recognition experiment where they were asked to discriminate between studied and non-studied words that varied in perceptual familiarity. The results indicated that participants were able to use perceptual familiarity to improve their level of recognition. More importantly, people with high cognitive reserve used familiarity better than those with low cognitive reserve. The results provide the first empirical evidence indicating that people with high cognitive reserve are more efficient at balancing recollection and familiarity processes, and thus maintain a better performance level than those with low cognitive reserve.

Familiarity Changes as a Function of Perceptual Shifts

This experiment compares the yes-no and forced recognition tests as methods of measuring familiarity. Participants faced a phase of 3 study-test recognition trials in which they studied words using all the letters of the alphabet (overlapping condition, O), and an additional phase in which targets and lures did not share any letters (non-overlapping condition, NO). Finally, subjects performed a forced-choice task in which they had to choose one of two new words, each from one of the subsets (Parkin et al., 2001). Results in the NO condition were better than in the O condition in the yes-no recognition test, while the forced-choice rate was significantly higher than .50, showing their sensitivity to familiarity. When the letter set of the words for study in the third list of the NO condition was switched, the difference between NO and O conditions disappeared in yes-no test, while the force-choice rate was not higher than .50. We conclude that both the yes-no test and the forced-choice test are valid and equivalent measures of familiarity under the right conditions.

Degree of elaborative processing in two implicit and two explicit memory tasks

The level of elaborative processing made by subjects to pairs of words (read vs. generated) and the degree of relationship between the words of each pair (related, rhymed, or rhymed and related) were manipulated on two explicit tasks (cued recall and recognition) and two implicit tasks (word-stem completion and tachistoscopic word identification) to test the empirical validity of the processing-approach theory (see, e.g., Roediger, 1990a, 1990b; Roediger, Srinivas, & Weldon, 1989) of explicit/implicit dissociations. Results give support to the predictions made by Roediger’s theory.