The Impact of Depression and Apathy on Sensory Language

Abstract

The debate that language strongly influences thought is equally met by those who suggest language does not influence thought. While historically, the ability to communicate with words was believed to be intimately tied to an ability to form thoughts, we would argue that thought and language are linked together through our sensory and motor systems and severely impacted by depression and apathy. We test this by conducting parts of speech analysis from the comparative longitudinal studies of two highly creative and prolific writers, where one is diagnosed with Alzheimer's disease (AD), and the other lives a long and healthy life. We calculate function and contents word ratios, measure lexical repetition, and the use of sensory-based words in textual language to test for depression and apathy in AD which is supported by MannWhitney U-Testing and Principal Component Analysis. Our results support the hypothesis that thought and language are impacted by depression and apathy and revealed in a person's writing style 12 years before a formal diagnosis of Alzheimer's disease presents. We find higher lexical repetition in language 12 years prior to one author being diagnosed with AD while not apparent in the other. We identify low olfactory word use and also find that an increased use of sensory-based adjectives might be a sign of the early onset of Alzheimer's disease.

The Lancaster Sensorimotor Norms: multidimensional measures of perceptual and action strength for 40,000 English words

“…For instance, we are currently using the norms to examine emergent conceptual structure from sensorimotor knowledge (Connell, Brand, Carney, Brysbaert, Banks, & Lynott, 2019;, and the role of sensorimotor experience in categorization (Banks, Wingfield, & Connell, 2019;van Hoef, Connell, & Lynott, 2019). Furthermore, the large size of the norms makes them amenable to some machine learning applications, such as using sensory language to identify early markers of clinical conditions (e.g., Kernot, Bossomaier, & Bradbury, 2017) or to inform recommender algorithms of therapeutic texts (Carney & Robertson, 2019). We hope the work presented here will prove useful for any researchers interested in the sensorimotor basis of word meaning and concepts.…”

Differences in type-token ratio and part-of-speech frequencies in male and female Russian written texts

“…E.g., it was shown to be significant in distinguishing Alzheimer's patients and healthy individuals, i.e. it is indicative of some personal cognitive features (Kernot et al, 2017). As far as gender identification is concerned, using Italian literary texts Bortolato (2016) showed that this parameter is more informative than frequencies of function words (particularly, conjunctions and pronouns) individually.…”