Biology subjects

Saez Garcia, M.

Publications and source records attributed to Saez Garcia, M..

2 recordsLinked to original sources

bioRxiv2022

Transient developmental increase in cortical projections to amygdala GABAergic neurons contribute to circuit dysfunction following early life stress

Early life stress (ELS) results in enduring dysfunction of the cortico-limbic circuitry, underlying emotional and social behavior. However, the neurobiological mechanisms by which ELS affects development of the circuitry remain elusive. Here, we have combined viral tracing and electrophysiological techniques to study the effects of maternal separation (MS) on fronto-limbic connectivity and function in young (P14-21) rats. We report that aberrant prefrontal (mPFC) inputs to basolateral amygdala (BLA) GABAergic interneurons transiently increase the strength of feedforward inhibition in the BLA, which raises LTP induction threshold in MS treated male rats. The enhanced GABAergic activity after MS exposure associates with lower functional synchronization within prefrontal-amygdala networks in vivo. Intriguingly, no differences in these parameters were detected in females, which were also resistant to MS dependent changes in anxiety-like behaviors. Impaired plasticity and synchronization during the sensitive period of circuit refinement may contribute to long-lasting functional changes in the prefrontal-amygdaloid circuitry that predispose to neuropsychiatric conditions later on in life.

neuroscience↗

bioRxiv2018

Revealing subthreshold motor contributions to perceptual confidence

Established models of perceptual metacognition, the ability to evaluate our perceptual judgments, posit that perceptual confidence depends on the strength or quality of feedforward sensory evidence. However, alternative theoretical accounts suggest the entire perception-action cycle, and not only variation in sensory evidence, is monitored when evaluating confidence in ones percepts. Such models lead to the counterintuitive prediction that perceptual confidence should be directly modulated by features of motor output. To evaluate this proposal here we recorded electromyographic (EMG) activity of motor effectors while subjects performed a near-threshold perceptual discrimination task and reported their confidence in each response. A subset of trials exhibited sub-threshold EMG activity in response effectors before a decision was made. Strikingly, trial-by-trial analysis showed that confidence, but not accuracy, was significantly higher on trials with subthreshold motor activation. These findings support a hypothesis that preparatory motor activity impacts upon confidence over and above performance, consistent with models in which perceptual metacognition integrates information across the perception-action cycle.

neuroscience↗