Fear prioritizes feedforward sensory coding at the expense of contextual processing in monkey V1

Area of Science:

• Neuroscience
• Computational Neuroscience
• Visual Processing

Background:

• The primary visual cortex (V1) processes visual information through both rapid feedforward and slower feedback mechanisms.
• Fear learning is known to influence V1 activity, but its precise impact on different processing stages and stimulus types is not fully understood.

Purpose of the Study:

• To investigate how fear conditioning modulates population coding in V1 for simple gratings versus complex contours.
• To determine if fear conditioning enhances all visual processing stages or selectively biases specific computations.

Main Methods:

• Monkeys underwent visual fear conditioning and V1 population activity was recorded using chronic microelectrodes.
• A Fisher linear discriminant classifier quantified stimulus discriminability (d') during early and late response epochs.

Main Results:

• Fear conditioning enhanced orientation decoding for gratings in the early epoch, indicating improved feedforward encoding.
• Decoding performance for contours was reduced in the late epoch after fear conditioning, suggesting impaired contextual processing.

Conclusions:

• Fear conditioning reconfigures V1 dynamics, prioritizing rapid feedforward threat detection.
• This prioritization comes at the expense of later, feedback-dependent contextual processing, representing an adaptive trade-off for threat detection.