Strobe rearing reduces direction selectivity in area 17 by altering spatiotemporal receptive-field structure

Area of Science:

• Neuroscience
• Visual Processing
• Developmental Biology

Background:

• Direction selectivity in the visual cortex is crucial for motion perception.
• This selectivity is linked to the spatiotemporal (S-T) receptive-field structure of neurons.
• S-T inseparable receptive fields, with response timing gradients, confer directional preference.

Purpose of the Study:

• To investigate the causal role of S-T receptive-field structure in developing direction selectivity.
• To examine the long-term effects of disrupted visual experience during development on neural circuits.
• To determine if strobe rearing permanently alters visual processing mechanisms.

Main Methods:

• Cats were reared from birth to 8 months in stroboscopic (8 Hz) illumination.
• Direction selectivity of simple cells in area 17 was measured using drifting gratings.
• Spatiotemporal receptive-field structure was assessed by analyzing responses to stationary bars with modulated luminance.

Main Results:

• Strobe rearing profoundly reduced direction selectivity, with only 10% of cells selective versus 80% in normal cats.
• The loss of direction selectivity was strongly correlated with a near-complete elimination of S-T inseparability.
• These deficits were specific, affecting only direction selectivity and S-T structure, and were permanent, lasting over 12 years.

Conclusions:

• Spatiotemporal receptive-field structure is critical for the development and maintenance of direction selectivity in visual cortical simple cells.
• Disrupting visual experience during a critical developmental period permanently alters neural circuit function.
• The visual system exhibits remarkable specificity in developmental plasticity, with strobe rearing selectively impacting directional tuning.