Juan José García Meilán

The effect of personality variables in the prediction of the execution of different prospective memory tasks in the laboratory

The study of prospective memory (ProM), the remembering of the delayed execution of intentions, has been growing in recent years, and we know quite a bit about the cognitive variables that affect it. But the performance of a task depends on personality variables as well as on cognitive ones, and the role of personality variables in ProM has only been partially studied, the results being less conclusive. We sought to address two main objectives: (1) to quantify the joint influence of cognitive and personality variables on three ProM tasks in the laboratory (two based on events and the other on time), and (2) to identify the personality profiles of those who perform well in these three ProM tasks as opposed to those who do not. The cognitive and personality variables were evaluated with two sessions of 157 participants. The 16 PF-5 was applied (Cattell, Cattell & Cattell, 1993) and other cognitive variables were measured. With the data obtained, we ran several regression analyses to determine how some cognitive variables (sustained attention, verbal fluency, interference, retrospective memory, selective attention) and personality factors (tested using the 16 PF-5) can help to explain the variance in the performance of prospective memory tasks. Our results show that the contribution of personality predictor variables is moderate and smaller than that of the cognitive variables for predicting the execution of ProM tasks in the laboratory. Furthermore the intervention of the personality variables differs depending on the ProM tasks used. Global self-control and rule-consciousness were the personality variables that contributed the most in the prediction of the scores in the ProM tasks that were used.

Speech in Alzheimer's Disease: Can Temporal and Acoustic Parameters Discriminate Dementia?

Aims: The study explores how speech measures may be linked to language profiles in participants with Alzheimers disease (AD) and how these profiles could distinguish AD from changes associated with normal aging. Methods: We analysed simple sentences spoken by older adults with and without AD. Spectrographic analysis of temporal and acoustic characteristics was carried out using the Praat software. Results: We found that measures of speech, such as variations in the percentage of voice breaks, number of periods of voice, number of voice breaks, shimmer (amplitude perturbation quotient), and noise-to-harmonics ratio, characterise people with AD with an accuracy of 84.8%. Discussion: These measures offer a sensitive method of assessing spontaneous speech output in AD, and they discriminate well between people with AD and healthy older adults. This method of evaluation is a promising tool for AD diagnosis and prognosis, and it could be used as a dependent measure in clinical trials.

Can the Acoustic Analysis of Expressive Prosody Discriminate Schizophrenia

Emotional states, attitudes and intentions are often conveyed by modulations in the tone of voice. Impaired recognition of emotions from a tone of voice (receptive prosody) has been described as characteristic symptoms of schizophrenia. However, the ability to express non-verbal information in speech (expressive prosody) has been understudied. This paper describes a useful technique for quantifying the degree of expressive prosody deficits in schizophrenia, using a semi-automatic method, and evaluates this methods ability to discriminate between patient and control groups. Forty-five medicated patients with a diagnosis of schizophrenia were matched with thirty-five healthy comparison subjects. Production of expressive prosodic speech was analyzed using variation in fundamental frequency (F0) measures on an emotionally neutral reading task. Results revealed that patients with schizophrenia exhibited significantly more pauses (p < .001), were slower (p < .001), and showed less pitch variability in speech (p < .05) and fewer variations in syllable timing (p < .001) than control subjects. These features have been associated with «flat» speech prosody. Signal processing algorithms applied to speech were shown to be capable of discriminating between patients and controls with an accuracy of 93.8%. These speech parameters may have a diagnostic and prognosis value and therefore could be used as a dependent measure in clinical trials.

Voice Markers of Lexical Access in Mild Cognitive Impairment and Alzheimer's Disease

BACKGROUND Recent studies have identified the correlation between dementia and certain vocal features, such as voice and speech changes. Vocal features may act as early markers of Alzheimers disease (AD). Despite being present in non-pathological senescence and Mild Cognitive Impairment, especially in its amnesic subtype (aMCI), these voice- and speech-related symptoms are the first signs of AD. The purpose of this study is to verify whether these signs are related to deficits in lexical access, which appear early in AD. METHOD Anomic deficits in persons with MCI and AD are assessed through tests on verbal memory, denomination by confrontation, and verbal fluency. In addition, an acoustic analysis of speech is conducted in a reading task to identify the acoustic parameters associated with the groups analyzed, and their relation to the degree of anomic impairment observed in each one of them. RESULTS AND CONCLUSIONS The results show a direct relationship between the different acoustic parameters present in AD and the verbal fluency tests results.

Improvement of encoding and retrieval in normal and pathological aging with word-picture paradigm.

Objectives: During the aging process, there is a progressive deficit in the encoding of new information and its retrieval. Different strategies are used in order to maintain, optimize or diminish these deficits in people with and without dementia. One of the classic techniques is paired-associate learning (PAL), which is based on improving the encoding of memories, but it has yet to be used to its full potential in people with dementia. In this study, our aim is to corroborate the importance of PAL tasks as instrumental tools for creating contextual cues, during both the encoding and retrieval phases of memory. Additionally, we aim to identify the most effective form of presenting the related items. Method: Pairs of stimuli were shown to healthy elderly people and to patients with moderate and mild Alzheimers disease. The encoding conditions were as follows: word/word, picture/picture, picture/word, and word/picture. Results: Associative cued recall of the second item in the pair shows that retrieval is higher for the word/picture condition in the two groups of patients with dementia when compared to the other conditions, while word/word is the least effective in all cases. Conclusion: These results confirm that PAL is an effective tool for creating contextual cues during both the encoding and retrieval phases in people with dementia when the items are presented using the word/picture condition. In this way, the encoding and retrieval deficit can be reduced in these people.

La influencia de la emoción en la memoria como índice para el diagnóstico temprano del Alzheimer

Introduction: during non-pathological aging the modulatory effect of emotion on memory is impaired, being particularly sensitive to amygdala and hippocampus atrophy that occurs in Alzheimers disease. Aim: the aim of this paper is to analyze how this affects the deterioration of affective states at the beginning and during development of the disease and how the difficulties in remembering emotional information could be used to study emotional valence and arousal levels, in order to develop a test capable of detecting these problems in early stages of the disease. Conclusions: in light of the studies consulted, we recommend the use of recognition instead free recall; multilevel emotional induction methods and greater sensitivity in the analysis of data using parameters based on Signal Detection Theory. The clinical implications of this approach focus on diagnosis, where emotion should be integrated at the same analysis level as memory and attention, and also in the experimental field, providing tools for neuroimaging studies with which to study biological bases of emotional dysfunction. (Alzheimer. Real Invest Demenc. 2011;48:33-38)

Relations between Sensorimotor Integration and Speech Disorders in Parkinson's Disease

BACKGROUND Sensorimotor integration mechanisms can be affected by many factors, among which are those involving neuromuscular disorders. Parkinsons disease (PD) is characterized by well-known motor symptoms, among which lately have been included motor speech deficits. Measurement of the acoustic startle reflex (ASR) and its modulations (prepulse inhibition and prepulse facilitation, PPI and PPF respectively) represent a simple and quantifiable tool to assess sensorimotor function. However, it remains unknown whether measures of the PPI and PPF are associated with motor speech deficits in PD. METHODS A total of 88 subjects participated in this study, 52 diagnosed with PD and 36 control subjects. After obtaining written informed consent, participants were assessed with PPI at several interstimulus intervals, and PPF at 1000 ms using the SRH-Lab system (San Diego, CA). Percentage of change in the amplitude and latency of the ASR was analyzed between groups. Voice recordings were register of a specific text given to the subjects with a professional recorder and temporal patterns of speech were analyzed. RESULTS Statistical analysis conducted in this study showed differences in PPI and PPF in subjects with PD compared to controls. In addition, discriminative parameters of voice abnormalities were observed in PD subjects related to control subjects showing a reduction in phonation time, vowel pulses, breaks, breakage and voice speech periods. CONCLUSIONS PD presents a disruption in sensorimotor filter mechanisms and speech disorders, and there is a relationship between these alterations. The correlation between the PPI and PPF with an alteration of the voice in PD subjects contributes toward understanding mechanism underlying the neurophysiological alterations in both processes. Overall, easy and non-invasive tests such as PPI, PPF together with voice analysis may be useful to identify early stages of PD.

Speech rhythm alterations in Spanish-speaking individuals with Alzheimer’s disease

ABSTRACT Rhythm is the speech property related to the temporal organization of sounds. Considerable evidence is now available for suggesting that dementia of Alzheimer’s type is associated with impairments in speech rhythm. The aim of this study is to assess the use of an automatic computerized system for measuring speech rhythm characteristics in an oral reading task performed by 45 patients with Alzheimer’s disease (AD) compared with those same characteristics among 82 healthy older adults without a diagnosis of dementia, and matched by age, sex and cultural background. Ranges of rhythmic-metric and clinical measurements were applied. The results show rhythmic differences between the groups, with higher variability of syllabic intervals in AD patients. Signal processing algorithms applied to oral reading recordings prove to be capable of differentiating between AD patients and older adults without dementia with an accuracy of 87% (specificity 81.7%, sensitivity 82.2%), based on the standard deviation of the duration of syllabic intervals. Experimental results show that the syllabic variability measurements extracted from the speech signal can be used to distinguish between older adults without a diagnosis of dementia and those with AD, and may be useful as a tool for the objective study and quantification of speech deficits in AD.