David & Simon Busch Moreno

The Meaning of Anxiety

David & Simon Busch Moreno

Students taking introductory modules in EEG and ERP analysis are especially invited to consider this project.

Background

Language processing is considered to be as highly distributedacross the brain, including bilateral hemispheric processing that is not redundant (Hickok and Poepple, 2007). This implies that different hemispheres process different types of information. Affective and prosodic features of language (in right handed individuals) have been associated with right hemisphere processing and high interaction with limbic areas of the brain (Costanzo et al., 2015). This has led to the proposition of a relationship between specific language processing features and mood affections. For the particular case of anxiety, rumination and sensitivity to threat are thought to be characteristic of high levels of trait or clinical anxiety(Nitschke et al., 1999). Neuroanatomically speaking pathways between limbic areas and prefrontal cortex are fundamental for the functioning of anxiety and problems within these areas are highly associated with pathological expressions of the anxious-depressive spectrum (Gray and Mcnaughton, 2000). EEG and fMRI evidence indicates that it is possible to distinguish between states of anxious arousal and anxious apprehension, where the first is associated with an immediate defensive response characterized by somatic arousal and closer to fear responses and the latter is associated with worry and “pure anxiety” as anticipation to potential threat or negative outcomes (Heller et al., 1997). Is it possible, then, to find neurological differences when comparing normal with anxious people responding to threatening and concerning language?

The project

The overarching research programme tests whether there is a difference in language processing between non-anxious and anxious apprehensive people, but first need to establish the nature of such effects in non-anxious individuals.This will be investigated by measuring EEG signals during a dichotic listening task. This type of task is used to collect behavioural measures (response times in the present study) that can indicate brain processing hemispheric biases. In a dichotic listening task,different stimuli are presented to each ear and participants have to respond to certain type of stimuli (e.g.: high vs low pitch syllables, negative words, etc.). The present dichotic listening task is a directed attention oddball variant (Wambacq and Jerger, 2004): participants are instructed to pay attention to only one ear and answer as fast as possible when they listen a negative sentence (25%) between several neutral sentences. Faster response times, for example, at the left ear would indicate faster processing or more engagement of the contralateral hemisphere (right).

The main task will be carrying out an EEG experiment using the mentioned dichotic listening task (programmedin PsychoPy) over a group of low anxious people. Experimental manipulations may include different kinds of content (e.g. sentences referring to threatening vs. concerning situations), and differences in expression (e.g. sentences produced in neutral tone vs. emotional prosody). The student (researcher) will be in charge of the whole EEG protocol and data analysis. This means: setting-up of EEG apparatus, testing participants, and analysing EEG raw data in the ERP paradigm. A student with noprevious experience in EEG testing will be assisted during the whole process.

Basic knowledge of stats and programming is required; Python and R programming skills are a plus. Strong interest in the neuroscience of language and/or affect/emotion will be very welcome as well.

References and suggested reading:

Costanzo, E., Villarreal, M., Drucaroff, L., Ortiz-Villafañe, M., Castro, M., Goldschmidt, M., Wainsztein, A., Ladrón-de-Guevara, M., Romero, C., Brusco, L., Camprodon, J., Nemeroff, C. and Guinjoan, S. (2015).Hemispheric specialization in affective responses, cerebral dominance for language, and handedness.Lateralization of emotion, language, and dexterity. DOI: 10.1016/j.bbr.2015.04.006

Gray, J. & Mcnaughton, N. (2000). The Neurophysiology of Anxiety: An enquiry into the functions of the septo-hippocampal system. Oxfor University Press, Oxford.

Heller, W.; Nitschke, J.; Etienne, M; & Miller, G. (1997). Patterns of Regional Brain Activity Differentiate Types of Anxiety. Journal of Abnormal Psychology, 106(3), 376-385.

Hickok, G. and Poeppel, D. (2007). The cortical organization of speech processing.Nature Reviews Neuroscience, 8(5), pp.393-402.

Nitschke, J., Heller, W., Palmieri, P. and Miller, G. (1999). Contrasting patterns of brain activity in anxious apprehension and anxious arousal.Psychophysiology, 36(5), pp.628-637.

Wambacq, I. and Jerger, J. (2004). Processing of affective prosody and lexical-semantics in spoken utterances as differentiated by event-related potentials.Cognitive Brain Research, 20(3), pp.427-437.