Perseverometry: a novel performance marker in dementia

Lead Research Organisation: St George's University of London
Department Name: Cardiovascular Medicine

Abstract

Patients with Alzheimer s disease are frequently noted by their relatives or carers to repeat themselves in conversation. In the early stages such behaviour might be regarded with no more than mild annoyance, but worsening of the tendency often motivates seeking a medical opinion, and leads eventually to the diagnosis of AD. With worsening of the disease, repetitions become more frequent, so if there were a means of measuring their occurence, this could be used as a diagnostic aid and a tool for monitoring the condition. Disease monitoring in particular is critical to the evaluation of novel drug treatments for Alzheimer s. Recording of patients conversations with their family members would be intrusive, and analysis of any such tape recorded record to look for repetitions would be a very laborious process. The solution we propose here is to make a continuous recording of energy fluctuations from the vocal apparatus. Such information would not be interpretable as language (thus safeguarding privacy) but could be rapidly and automatically processed to reveal segments that represented a previously repeated statement or phrase (solving the practical problems of interpretation). The aim of the present study is to determine the best methods for acquiring and analysing the data, and to establish the feasibility of such a recording method from AD patients as they go about their day to day lives.

Technical Summary

Perseveration is an abnormal form of behaviour in which a speaker excessively repeats the same words, phrases or actions. Perseverative speech is a common presenting feature of Alzheimer s disease (AD) and becomes more prominent as the condition progresses. Recording the occurrence and severity of such behaviour would thus provide not only a measurable diagnostic marker of AD, but also a means of monitoring the patient s clinical course. The latter would be particularly important when evaluating the response to disease-modifying treatments. Continuous recording of an individual s speech in a real world setting, however, would not only violate the privacy of patients and their associates or carers, but would be difficult to interpret without manually segmenting the sources of recorded speech. A data source that was both devoid of linguistic meaning and automatically interpretable using signal processing technology can be achieved by recording acoustic energy rather than speech. The present study aims to develop and test a device and analytical method for capturing and interpreting this information in real world environments, allowing perseverative speech to be detected and quantified.

Publications

10 25 50
 
Title Bone conducted speech samples 
Description Monitoring bone conducted speech by continuous electronic recording using an accelerometer fixed to a subjects temporo-mandibular joint. 
Type Of Material Technology assay or reagent 
Year Produced 2014 
Provided To Others? No  
Impact None yet, but funding for a larger study involving the technique on different patient groups will be made. 
 
Title Motif discovery in bone-conducted speech 
Description A procedure for identifying repeated segments of speech (perseverations) in patients with amnestic difficulties, such as Alzheimer's disease. 
Type Of Material Technology assay or reagent 
Year Produced 2014 
Provided To Others? No  
Impact We are about to undertake a pilot study of the technique in samples obtained by monitoring AD patients in their homes. 
 
Description Application of a sensor glove to the assessment of dyspraxia in Alzheimer's disease 
Organisation Leeds Beckett University
Country United Kingdom 
Sector Academic/University 
PI Contribution Proposal of dyspraxia as an application for the device
Collaborator Contribution Provision of a prototype of the device for pilot testing
Impact Nil yet
Start Year 2018
 
Description Collaboration with ISVR in Southampton 
Organisation University of Southampton
Department Faculty of Health Sciences
Country United Kingdom 
Sector Academic/University 
PI Contribution We share a postdoc who is learning advance signal processing and programming techniques from Southampton while identifying and testing patients in London using the bone conducted speech monitoring device.
Collaborator Contribution The development of a motif discovery algorithm suitable for extracting information of interest from data acquired from patients and controls both under laboratory conditions and 'in the field' has been developed and preliminary analysis suggests that perseverative utterances can be detected and quantified. The computational demands of this processing task were significant, but Dr Barney's group continues to work on refining the method, which is seen as a novel and difficult signal processing problem. The plan is to submit details of the method to a technical scientific journal in the signal processing field.
Impact A report of the project's output will be displayed at the International Conference on Alzheimer's disease in 2012 The collaboration involves a neurologist (Dr Garrard) and a signal processing engineer (Dr Barney). Dr Barney has recently started supervising a new PhD student, and part of the student's research project will involve analysing conversational speech samples in collaboration with Dr Garrard's research group at SGUL.
Start Year 2010
 
Description AAIC 2012 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Type Of Presentation Paper Presentation
Geographic Reach International
Primary Audience Other academic audiences (collaborators, peers etc.)
Results and Impact The AAIC is the largest international meeting on dementia research, and acceptance of an abstract for oral presentation is highly prestigious. The paper was presented by the postdoctoral researcher on the project at a session featuring some of the most important figures currently active in Alzheimer's disease and MCI research, and was given a warm reception by a large audience. The experience and prestige that this afforded to the postdoctoral researcher was considerable. The exposure that it provided to the work of the project was likewise highly significant.

A number of inquiries were made by high profile research groups into the methods used in this work.
Year(s) Of Engagement Activity 2012