Research Study - Phasic boosting of attentional capabilities with a Forbrain session

By Dr. Carles Escera

Note - This is a research in progress

Work: We will focus our testing only on the parameters that yielded significant results in our previous study: the ATTN test, heart rate, skin conductance, and voice variables. The design will be very similar to that used in the previous study, with the following changes:  

1. Instead of a single case design (N=1 participant) there now be 32 subjects (N=32 participants) and

2. Half (n=16) of the participants will be randomly assigned to a control (“placebo”) group in which the Forbrain device will be kept off during the whole session.

Because in our initial study robust effects appeared after one single session of use, we will have one single session per participant. However, before starting the actual experiment, we will collect some dummy data on all three measurements to allow the participant to become acquainted with the laboratory procedures and thus avoid the undesired effects for heart rate we observed during session 1 in our previous experiment. The protocol for the study will be therefore as follows:

• Accommodation of the laboratory procedures
• ATTN test pre-use (2 runs of 10 minutes)
• Physiological and voice recordings during reading (Forbrain off) – (7 minutes)
• Physiological and voice recordings during reading (Forbrain on) – (15 minutes). Notice however that for the control (placebo) group, Forbrain will be kept off during the whole laboratory session.
• Physiological and voice recordings during reading (Forbrain off) – (7 minutes)
• ATTN test post-use (2 runs of 10 minutes)

Impact: The proposed design, a controlled placebo, eventually double-blind study (at least, the participants won’t be informed about which group they are in, and the researcher analyzing the data will ignore the group assignment until the conclusions are drawn), will provide the strongest evidence in support of the phasic effects of Forbrain. We expect to replicate our previous single-case findings. If so, it is anticipated that a highly impactful scientific publication will result from this study.

Methodology: To test for attentional capabilities, concentration, and the ability to cope with involuntary attention, the participant’s performance on a task in which they have to cope with distracters, as well as the brain responses triggered by these distracters (the distraction potential --DP, including mismatch negativity –MMN, novelty-P3, and reorienting negativity –RON) will be used (see Escera et al., 1998; Escera and Corral, 2007). [ATT test].

In addition, the effects of Forbrain on voice quality and on emotional arousal will be tested. The former will be checked by recording the participant's voice during reading; the latter will be checked by measuring electrodermal activity (EDA) and the electrocardiogram (EKG) to derive heart rate.

Subjects. A total of N=32 participants will be enrolled. They will be healthy university students (age range 18-35 years; male or female) with no history of neurological or psychiatric disorders and normal hearing (hearing level will be determined through standard audiometry). Music expertise will be disregarded, as it has been shown to enhance the encoding of speech sound features and auditory discrimination.

The experiment will be conducted in accordance with the Code of Ethics of the World Medical Association (Declaration of Helsinki). Before the experimental session, all the details of the research (except the hypotheses) will be explained to the participant, who will be informed also about the characteristics of the methods (EEG).

During the active speech protocol, the participant will be given a self-selected text and will be instructed to read aloud for a period of 15 consecutive minutes, while wearing the Forbrain device.

Stimulus presentation and EEG recording. [ATT test] To measure involuntary attention control, a distraction paradigm will be used. In this paradigm, participants are instructed to discriminate visual stimuli (consonants and vowels) while ignoring the preceding auditory stimulus. The sound-letter pairs are presented every 1.2 seconds, and subjects are instructed to press the corresponding response button (consonant/vowel) as fast and as accurately as possible. Critically, most of the sounds consist of a repeated tone pip, which is occasionally replaced by a “distracting” novel sound. In addition, brain responses are recorded to the distracting sounds to isolate the neural signatures of the three stages of involuntary attention control: detecting the distracter (MMN), orienting of attention (novelty-P3), restoring attention to primary task performance (RON) (Escera and Corral, 2007).

The EEG will be recorded at the premises of the Brainlab-Cognitive Neuroscience Research Group located in the Department of Psychiatry and Clinical Psychobiology, University of Barcelona, by means of a SynAmpsRT amplifier. Acquisition parameters will be set to 20000 kHz sampling rate, filter settings: 0.5-2000 Hz, and recordings will be obtained from at least 7 scalp locations (FPz, Fz, Cz, F3, F4, C3, C4); larger set-ups may be considered to record the DP.

An independent component analysis (ICA) blind procedure will be used to scan all EEG epochs for artifacts, and those with artifacts will be excluded from the averages. Responses will be analyzed separately by individual and condition. The dependent variables will be: the harmonic amplitudes of the FFR elicited to the CV /da/ in the two contexts (silent and speech-in-noise); the amplitude and latency of the MMN elicited to F0, INT, voD, voI deviants; and the response time and hit rate to visual targets preceded by repeated and novel sounds as well as the amplitude of the MMN, novelty-P3 and RON responses elicited to the distracters. A statistical approach based on time series analysis will be applied to the data.