Remote testing in Abbiategrasso (RTA): results from a counterbalanced cross-over study on direct-to-home neuropsychology with older adults.

BACKGROUND: The SARS-CoV-2 pandemic forced to rethink teleneuropsychology, since neuropsychological assessments started to be performed by phone or videoconference, with personal devices and without direct assistance from the clinician, a practice called "Direct-To-Home NeuroPsychology" (DTH-NP). AIMS: The present study, employing a counterbalanced cross-over design, was aimed at evaluating (1) the feasibility and (2) the acceptability of DTH-NP in Italian older adults without previously diagnosed neurocognitive disorder, (3) the comparability between remote and face-to-face administration of selected neuropsychological tests. METHODS: Fifty-eight community-dwelling older adults (65-85 years) were randomly assigned to one of two groups performing a complete neuropsychological assessment remotely (via phone call and videoconference) and face-to-face, in a counterbalance order, 8 weeks apart. The study recruitment rate was calculated, and the number of uncompleted tests and acceptability questionnaire responses were compared between the two administration modalities. Comparability was defined as good reliability of DTH-NP (intraclass correlation coefficient) and agreement between remote and face-to-face scores (Bland-Altman plots). RESULTS: Recruitment rate was 81%, with a preference for telephonic contact (79%). The acceptability analysis did not reveal any issues related to the DTH-NP assessment, even if most participants would rather repeat it face-to-face. Tests assessing short-term memory, language, and reasoning showed good comparability. DISCUSSION AND CONCLUSION: Our results point out to a good recruitment rate in a DTH-NP study in an Italian population of older adults (mean age = 80), satisfying acceptability of DTH-NP and remote-face-to-face comparability of certain verbally mediated tests. Further studies including larger samples in videoconference modality, and outpatients, could better clarify its strengths and limits.

Functional connectivity within the voice perception network and its behavioural relevance.

Recognizing who is speaking is a cognitive ability characterized by considerable individual differences, which could relate to the inter-individual variability observed in voice-elicited BOLD activity. Since voice perception is sustained by a complex brain network involving temporal voice areas (TVAs) and, even if less consistently, extra-temporal regions such as frontal cortices, functional connectivity (FC) during an fMRI voice localizer (passive listening of voices vs non-voices) has been computed within twelve temporal and frontal voice-sensitive regions ("voice patches") individually defined for each subject (N = 90) to account for inter-individual variability. Results revealed that voice patches were positively co-activated during voice listening and that they were characterized by different FC pattern depending on the location (anterior/posterior) and the hemisphere. Importantly, FC between right frontal and temporal voice patches was behaviorally relevant: FC significantly increased with voice recognition abilities as measured in a voice recognition test performed outside the scanner. Hence, this study highlights the importance of frontal regions in voice perception and it supports the idea that looking at FC between stimulus-specific and higher-order frontal regions can help understanding individual differences in processing social stimuli such as voices.

The Glasgow Voice Memory Test: Assessing the ability to memorize and recognize unfamiliar voices.

One thousand one hundred and twenty subjects as well as a developmental phonagnosic subject (KH) along with age-matched controls performed the Glasgow Voice Memory Test, which assesses the ability to encode and immediately recognize, through an old/new judgment, both unfamiliar voices (delivered as vowels, making language requirements minimal) and bell sounds. The inclusion of non-vocal stimuli allows the detection of significant dissociations between the two categories (vocal vs. non-vocal stimuli). The distributions of accuracy and sensitivity scores (d') reflected a wide range of individual differences in voice recognition performance in the population. As expected, KH showed a dissociation between the recognition of voices and bell sounds, her performance being significantly poorer than matched controls for voices but not for bells. By providing normative data of a large sample and by testing a developmental phonagnosic subject, we demonstrated that the Glasgow Voice Memory Test, available online and accessible from all over the world, can be a valid screening tool (~5 min) for a preliminary detection of potential cases of phonagnosia and of "super recognizers" for voices.

FMRI-based identity classification accuracy in left temporal and frontal regions predicts speaker recognition performance.

Speaker recognition is characterized by considerable inter-individual variability with poorly understood neural bases. This study was aimed at (1) clarifying the cerebral correlates of speaker recognition in humans, in particular the involvement of prefrontal areas, using multi voxel pattern analysis (MVPA) applied to fMRI data from a relatively large group of participants, and (2) at investigating the relationship across participants between fMRI-based classification and the group's variable behavioural performance at the speaker recognition task. A cohort of subjects (N = 40, 28 females) selected to present a wide distribution of voice recognition abilities underwent an fMRI speaker identification task during which they were asked to recognize three previously learned speakers with finger button presses. The results showed that speaker identity could be significantly decoded based on fMRI patterns in voice-sensitive regions including bilateral temporal voice areas (TVAs) along the superior temporal sulcus/gyrus but also in bilateral parietal and left inferior frontal regions. Furthermore, fMRI-based classification accuracy showed a significant correlation with individual behavioural performance in left anterior STG/STS and left inferior frontal gyrus. These results highlight the role of both temporal and extra-temporal regions in performing a speaker identity recognition task with motor responses.

Single-trial fMRI activation maps measured during the InterTVA event-related voice localizer. A data set ready for inter-subject pattern analysis.

Multivariate pattern analysis (MVPA) of functional neuroimaging data has emerged as a key tool for studying the cognitive architecture of the human brain. At the group level, we have recently demonstrated the advantages of an under-exploited scheme that consists in training a machine learning model on data from a set of subjects and evaluating its generalization ability on data from unseen subjects (see Inter-subject pattern analysis: A straightforward and powerful scheme for group-level MVPA [1]). We here provide a data set that is fully ready to perform inter-subject pattern analysis, which includes 5616 single-trial brain activation maps recorded in 39 participants who were scanned using functional magnetic resonance imaging (fMRI) with a voice localizer paradigm. This data set should therefore reveal valuable for data scientists developing brain decoding algorithms as well as cognitive neuroscientists interested in voice perception.

Progressive phonagnosia in a telephone operator carrying a C9orf72 expansion.

Selectivity is the rule, rather than the exception, in neurodegenerative disease. A retired telephone operator carrying a C9orf72 expansion developed phonagnosia, a selective impairment of voice recognition, contrasting with intact person knowledge and recognition of faces, as a presenting sign of genetically confirmed fronto-temporal dementia. Since the dysfunction in this patient fell into his area of professional expertise, we discuss if overload in voice related neural networks might have caused failure propagating to connected nodes. The interaction with downstream molecular events, triggered by the C9orf72 expansion, may have led to breakdown at the network level, leading to this specific phenotype.

A "voice patch" system in the primate brain for processing vocal information?

We review behavioural and neural evidence for the processing of information contained in conspecific vocalizations (CVs) in three primate species: humans, macaques and marmosets. We focus on abilities that are present and ecologically relevant in all three species: the detection and sensitivity to CVs; and the processing of identity cues in CVs. Current evidence, although fragmentary, supports the notion of a "voice patch system" in the primate brain analogous to the face patch system of visual cortex: a series of discrete, interconnected cortical areas supporting increasingly abstract representations of the vocal input. A central question concerns the degree to which the voice patch system is conserved in evolution. We outline challenges that arise and suggesting potential avenues for comparing the organization of the voice patch system across primate brains.