Can Spheric Speech Clarity support how we think in noise?

New evidence shows that SSC, the AI-powered noise reduction feature in Infinio, may do more than improve hearing — it may also help users stay more focused and engaged in everyday communication.

In the first part of this series, we introduced cognitive functions involved in everyday listening: interference control, processing speed, and working memory.

In this post, we focus on a recent study that explored whether Phonak’s Spheric Speech Clarity (SSC) —an advanced noise reduction feature on the Infinio platform— can support these functions by reducing the mental effort required to listen in noise. SSC uses deep neural networks (DNNs) trained to extract speech from complex, noisy environments.

Study design: Isolating the effect of SSC

The study involved 18 experienced hearing aid users with mild to moderate sensorineural hearing loss participated in the study. Each was fitted with Phonak Audéo I90-Sphere hearing aids and tested using three program settings:

Real Ear Sound (RES) – no noise reduction
Fixed Directional (FD) – directional microphone only
FD with SSC – directional microphone plus SSC noise reduction

This allowed researchers to isolate the specific impact of SSC from the effects of directionality alone.

Task 1: Interference control and processing speed

Participants sat in a noisy environment and completed an Auditory Stroop Task. They had to identify the pitch (high or low) of a word, ignoring its semantic meaning. For example, they might hear the word “high” spoken in a low-pitched voice.

To respond correctly, they had to suppress misleading semantic cues and focus on the acoustic properties of the word — a task that requires cognitive inhibition and quick decision-making (see Figure 1).

Figure 1: Illustrates the Auditory Stroop Task required participants to quickly identify the pitch of a stimulus and press either the “high” or “low” button.

> Two participants performed at chance level (50%) and were excluded from analysis to ensure the results reflected meaningful engagement with the task.

Key finding:
Participants responded significantly faster to incongruent stimuli when using the SSC program, compared to both the directional-only and no noise reduction settings. This suggests that SSC supports faster and more accurate cognitive processing in noisy environments.

Task 2: Working memory in noise

In a second test, participants completed a Backward Digit Span (BDS) task in background noise. They heard a series of digits (e.g., 5–2–8) and were asked to repeat them in reverse order. Each time they succeeded, the sequence grew longer, until they failed two trials at the same length (see Figure 2).

Figure 2: Example of one of the trials where participants had to enter digits in reverse order.

A longer BDS indicates better working memory — the ability to retain and manipulate information while filtering out distractions.

Key finding:
With SSC, participants were able to accurately recall longer digit sequences than with the no noise reduction program. This reflects enhanced working memory performance in noisy environments.

What this means for daily life

These results suggest that SSC doesn’t just help people hear more clearly — it may also help them think more clearly.

By supporting cognitive processes like interference control, processing speed, and working memory, SSC may make it easier for hearing aid users to:

Follow fast-paced conversations
Remember verbal instructions
Handle complex or multi-step tasks in noisy settings

In short, SSC may reduce the mental load of listening — helping users stay more focused and engaged in everyday communication.

To learn more about this study, check out the Field Study News on the Phonak Evidence Page. Link

To learn more about Phonak Audéo Sphere Infinio, we invite you to visit the Phonak website.