Amacrine cells

Amacrine cells are interneurons in the human retina that interact with retinal ganglion cells and/or bipolar cells.

  • Amacrine cells are a type of interneuron within the human retina.
  • Amacrine cells are embedded in the retinal circuitry.
  • Amacrine cells are activated by, and feedback to, bipolar cells. They also have junctions with ganglion cells, as well as with each other.
  • Amacrine cells send complex spatial and temporal information about the visual world to ganglion cells.
  • Amacrine cells are known to add information to the stream of data travelling through bipolar cells and then to control and refine the way ganglion cells (and their subtypes) respond to it.
  • Most amacrine cells don’t have tale-like axons. But whilst they clearly have multiple connections to other neurons around them, research into their precise inputs and outputs is ongoing.
  • Axons are the part of neurons that transmit electrical impulses to other neurons.
  • Neurons are the nerve cells that the human central nervous system is composed of.
About amacrine cell functions

Amacrine cells are known to contribute to narrowly task-specific visual functions such as:

  • Efficient transmission of high fidelity visual information with a good signal-to-noise ratio.
  • Maintaining the circadian rhythm which keeps our lives tuned to the cycles of day and night and helps to govern our lives throughout the year.
  • Measuring the difference between the response of specific photoreceptors compared with surrounding cells (centre-surround antagonism), so enabling edge detection and contrast enhancement.
  • Motion detection and the ability to distinguish between the movement of things across the field of view and our own eye movements.
About centre-surround antagonism

Centre-surround antagonism refers to the way retinal neurons organize their receptive fields.

  • Centre-surround antagonism refers to the way that light striking the human retina is processed by groups of light-sensitive cone cells.
  • The centre component is primed to measure the sum-total of signals received from a small number of cone cells directly connected to a bipolar cell.
  • The surround component is primed to measure the sum of signals received from a much larger number of cones around the centre point.
  • The two signals are then compared to find the degree to which they disagree.