Pronunciation: [hˌɒɹɪzˈɒntə͡l sˈɛl] (IPA) 
The spelling of the word "horizontal cell" is fairly straightforward. The first syllable "hor-" is pronounced with an /h/ sound followed by the short /ɔ/ sound, and the second syllable "-i-" is pronounced with a long /aɪ/ sound. The final syllable "-zontal" is pronounced with the /z/ sound, the long /o/ sound, and the short /əl/ sound. Altogether, the IPA phonetic transcription for "horizontal cell" is hɔraɪzɑntəl sɛl.
A horizontal cell refers to a specialized type of neuron found in the retina of the eye. It plays a crucial role in mediating lateral interactions between photoreceptor cells and bipolar cells, contributing to visual processing.
Characterized by their horizontally oriented processes, these cells are typically classified into two main types: the horizontal cells associated with cone photoreceptors (H1) and those associated with rod photoreceptors (H2). Both types function to modulate the transmission of visual signals from photoreceptor cells to bipolar cells, which subsequently transmit the information to ganglion cells for further processing.
The main function of horizontal cells is to provide inhibitory feedback and lateral inhibition within the retina. By receiving input from photoreceptor cells and synapsing with both photoreceptor and bipolar cells, horizontal cells can alter the strength of signals transmitted from photoreceptor cells to bipolar cells.
This lateral inhibition mechanism plays a crucial role in enhancing visual contrast and sharpening the perception of visual stimuli. By inhibiting neighboring photoreceptor cells, horizontal cells effectively enhance the spatial resolution and boundary detection ability of the visual system.
In addition to their role in contrast enhancement, horizontal cells are also involved in regulating the receptive fields of bipolar cells and adjusting the sensitivity of the retina to light. Overall, horizontal cells contribute significantly to the intricate neural network of the retina, facilitating efficient visual processing and accurate perception.
The etymology of the word "horizontal cell" is derived from the combination of two terms: "horizontal" and "cell".
- "Horizontal" is derived from the Latin word "horizontem" or "horizōn", which means "level" or "boundary". It refers to something that is parallel to the horizon or level with the observer's eye. The term "horizontal" is commonly used in geometry and describes a direction or position that is parallel to the Earth's surface, typically from left to right.
- "Cell" comes from the Latin word "cella", which means "small compartment" or "small room". The term "cell" is commonly used in biology to refer to the structural and functional unit of all living organisms.
