28.01.2015

Auditory intelligence in the rat brain

We study auditory cognitive functions of rats by recording local-field potentials from the cortical and subcortical brain structures. The main goal is to reveal human-animal similarities in the sensory-cognitive processing, and unravel the neural mechanisms of perceptual learning.

 

Research Description

We study auditory abilities of different levels of cognitive complexity from change detection in simple sound features such as frequency to receptive speech -related higher-order cognitive functionsfunctions. In this work, an animal model based on urethane-anesthetized rats is utilized. So called mismatch negativity (MMN) of event-related potentials (ERPs) is a feasible tool for our purposes. It is an electrophysiological measure that can be used to test auditory cognitive functions related to basic auditory and language mechanisms in humans and animals (Näätänen et al, 2010). MMN is automatically elicited in the brain when any discriminable change  occurs in auditory stimulation.

We have found that rare changes in sinusoidal sound frequency (Astikainen et al., 2011) as well as changes in speech sounds (Ahmed et al., 2011) are detected in the rat brain based on a short-term (transient) memory representation of the repeated sounds. Changes in sound duration are processed in the auditory cortical and hippocampal structures in the brain (Ruusuvirta et al., 2013). Rats are also able to represent sounds as feature combinations (Astikainen et al., 2006) as well as abstract attributes across several sounds (Ruusuvirta et al., 2007; Astikainen et al., 2014b). Our recent studies have elucidated the ability of the anaesthetized rat brain to detect changes in abstract grammar-like rules from speech sound patterns (Astikainen et al., 2014a).

 

People

Leader

Dr. Piia Astikainen, PhD

 

Group members

Dr. Miriam Nokia, PhD

Dr. Markku Penttonen, PhD

Dr. Tanel Mällo, PhD

Dr. Arto Lipponen, PhD

 

MA students

Eeva Pellinen (2012-2013)

 

Collaborators

Professor Risto Näätänen, University of Tartu, Estonia

Professor Fengyu Cong, PhD

Dr. Timo Ruusuvirta, PhD

 

Selected publications

Ahmed, M., Mällo, T., Leppänen, P., Hämäläinen, J., Äyräväinen, L., Ruusuvirta, T. & Astikainen, P. (2011). Mismatch brain response to speech sound changes in rats. Frontiers in Psychology, 2 (283).

Astikainen, P., Mällo, T., Ruusuvirta, T. & Näätänen, R. (2014a). Electrophysiological evidence for change detection in speech sound patterns by anesthetized rats. Frontiers in Auditory Cognitive Neuroscience, 8:374. doi: 10.3389/fnins.2014.00374

Astikainen, P., Ruusuvirta, T. & Näätänen, R. (2014b). Rapid categorization of sound objects in anesthetized rats as indexed by the electrophysiological mismatch response. Psychophysiology, 51, 1195–1199. DOI: 10.1111/psyp.12284

Astikainen, P., Ruusuvirta, T., Wikgren, J. & Penttonen, M. (2006). Memory-based detection of rare sound feature combinations in anesthetized rats. NeuroReport, 17, 1561-1564.

Astikainen, P., Stefanics, G., Nokia, M., Lipponen, A., Cong, F., Penttonen, M. & Ruusuvirta, T. (2011). Memory-based mismatch response to frequency changes in rats. PLoS ONE, 6 (9).

Näätänen, R., Astikainen, P., Ruusuvirta, T. & Huotilainen, M. (2010). Automatic auditory intelligence: An expression of the sensory-cognitive core of cognitive processes. Brain Research Reviews, 64 (1), 123-136.

Ruusuvirta, T., Koivisto, K., Wikgren, J. & Astikainen, P. (2007). Processing of melodic contours in urethane-anaesthetized rats. European Journal of Neuroscience, 26 (3), 701-703.

Ruusuvirta, T., Lipponen, A., Pellinen, E., Penttonen, M., & Astikainen P. (2013). Auditory cortical and hippocampal-system mismatch responses to duration deviants in urethane-anesthetized rats. PLoS One, 8(1):e54624.

 

Funding

2009-2012: Grant for research project “Primitive auditory intelligence in the rat brain”, Academy of Finland, 400 000 €, PI Piia Astikainen