近くの音の位置をニューロンで表現する
M S Graziano1, L A Reiss, C G Gross
1Department of Psychology, Princeton University, New Jersey 08544, USA. graziano@princeton.edu
Nature
|February 16, 1999
まとめ
科学者たちは,マカク類猿のニューロンを発見した.
科学分野:
- 神経科学は神経科学である.
- 聴覚知覚とは,聴覚の知覚である.
- 空間ナビゲーション 空間ナビゲーション
背景:
- 人間は,距離を含む音源の位置を正確に決定することができます.
- 聴覚的遠隔感知機構は十分に理解されていない.
- 聴覚距離のニューラルエンコーディングは,音の方向とは異なり,ほとんど知られていない.
研究 の 目的:
- 頭部付近の聴覚空間の神経表現を調査する.
- 聴覚的な距離知覚に関与する脳領域を特定する.
- 近場聴覚空間をコードするニューロンを特徴づける.
主な方法:
- マカカ猿 (Macaca fascicularis) の神経活動が記録されました.
- ベントラル・プレモーター皮質のニューロンに焦点を当てた.
- 聴覚ニューロンの空間的受容場をマッピングした.
主要な成果:
- 頭から約30cm以内の聴覚空間を表すニューロンを特定した.
- これらのニューロンは,腹前運動皮質に位置しています.
- ニューロンは,頭から外へと広がる空間的受容場を示します.
結論:
- 腹前運動皮質には,近場の聴覚空間をコードするニューロンが含まれています.
- これらの発見は,聴覚的な距離知覚の神経基礎についての洞察を提供します.
- この研究は,脳が身体に近い音の処理方法を明らかにしています.
関連する概念動画
Hearing
When we hear a sound, our nervous system is detecting sound waves—pressure waves of mechanical energy traveling through a medium. The frequency of the wave is perceived as pitch, while the amplitude is perceived as loudness.
Hair Cells
Hair cells are the sensory receptors of the auditory system—they transduce mechanical sound waves into electrical energy that the nervous system can understand. Hair cells are located in the organ of Corti within the cochlea of the inner ear, between the basilar and tectorial membranes. The actual sensory receptors are called inner hair cells. The outer hair cells serve other functions, such as sound amplification in the cochlea, and are not discussed in detail here.
The Cochlea
The cochlea is a coiled structure in the inner ear that contains hair cells—the sensory receptors of the auditory system. Sound waves are transmitted to the cochlea by small bones attached to the eardrum called the ossicles, which vibrate the oval window that leads to the inner ear. This causes fluid in the chambers of the cochlea to move, vibrating the basilar membrane.
Association Areas of the Cortex
Association areas are regions of the cerebral cortex that do not have a specific sensory or motor function. Instead, they integrate and interpret information from various sources to enable higher cognitive processes such as memory, learning, and decision-making. Some key association areas include the following:
Prefrontal Association Area: This area is located in the frontal lobe and is involved in planning, decision-making, and moderating social behavior. It connects with primary motor areas,...
Prefrontal Association Area: This area is located in the frontal lobe and is involved in planning, decision-making, and moderating social behavior. It connects with primary motor areas,...
Auditory Pathway
Auditory pathways constitute the complex neural circuits responsible for transmitting and interpreting auditory information from the peripheral auditory system to the brain. Sound waves are initially captured by the outer ear, funneled through the ear canal, and reach the tympanic membrane (eardrum). These vibrations are transmitted via the middle ear's ossicles to the inner ear's cochlea.
When viewed cross-sectionally, the cochlea reveals the scala vestibuli and scala tympani flanking the...
When viewed cross-sectionally, the cochlea reveals the scala vestibuli and scala tympani flanking the...
Perceiving Loudness, Pitch, and Location
The human brain perceives pitch through two primary mechanisms reflected in place theory and frequency theory. Each mechanism describes how sound waves are interpreted as specific pitches by the brain, offering insights into the intricate processes of auditory perception.
Place theory, or place coding, suggests that different pitches are heard because various sound waves activate specific locations along the cochlea's basilar membrane. The brain determines the pitch of a sound by identifying...
Place theory, or place coding, suggests that different pitches are heard because various sound waves activate specific locations along the cochlea's basilar membrane. The brain determines the pitch of a sound by identifying...


