A functional circuit for the retrieval of remote cued fear memory.
Although the retrosplenial cortex (RSC) is necessary for the retrieval of remotely acquired fear to a discrete auditory cue, it is not necessary for the retrieval of recently acquired cued-fear memories. Thus, the RSC’s role in memory retrieval for discrete cues is time-dependent. The purpose of the current experiment was to identify the larger cortical circuit involved in the retrieval of remotely-acquired auditory fear memories. One candidate circuit involves the RSC and secondary auditory cortex; the secondary auditory cortex is also necessary for the retrieval of remotely acquired auditory fear memories (Sacco & Sacc...
Source: Behavioral Neuroscience - June 4, 2018 Category: Neuroscience Source Type: research
Retrosplenial cortex has a time-dependent role in memory for visual stimuli.
Although the retrosplenial cortex (RSC) is critically involved in spatial learning and memory, it appears to have more selective contributions to learning and memory for discrete cues. For example, damage to the RSC does not impair Pavlovian delay fear conditioning to a discrete auditory cue (e.g., tone), when RSC manipulation occurs just prior to, or shortly after, conditioning. In contrast, when lesions of the RSC occur following a substantial retention interval (e.g., 28 days), the RSC is necessary for retrieval of fear to the tone. Thus, the RSC makes time-dependent contributions to memory retrieval for discrete audito...
Source: Behavioral Neuroscience - June 4, 2018 Category: Neuroscience Source Type: research
Task-dependent modulation of spinal and transcortical stretch reflexes linked to motor learning rate.
It is generally believed that task-dependent control of body configuration (“posture”) is achieved by adjusting voluntary motor activity and transcortical “long-latency” reflexes. Spinal monosynaptic circuits are thought not to be engaged in such task-level control. Similarly, being in a state of motor learning has been strongly associated only with an upregulation of feedback responses at transcortical latencies and beyond. In two separate experiments, the current study examined the task-dependent modulation of stretch reflexes by perturbing the hand of human subjects while they were waiting for a “Go” signal ...
Source: Behavioral Neuroscience - May 28, 2018 Category: Neuroscience Source Type: research
Exposure to bright light biases effort-based decisions.
Secreted in the evening and the night, melatonin suppresses activity of the mesolimbic dopamine pathway, a brain pathway involved in reward processing. However, exposure to bright light diminishes—or even prevents—melatonin secretion. Thus, we hypothesized that reward processing, in the evening, is more pronounced in bright light (vs. dim light). Healthy human participants carried out three tasks that tapped into various aspects of reward processing (effort expenditure for rewards task [EEfRT]; two-armed bandit task [2ABT]; balloon analogue risk task [BART). Brightness was manipulated within-subjects (bright vs. dim li...
Source: Behavioral Neuroscience - May 28, 2018 Category: Neuroscience Source Type: research
Early adolescent adversity inflates threat estimation in females and promotes alcohol use initiation in both sexes.
Childhood adversity is associated with exaggerated threat processing and earlier alcohol use initiation. Conclusive links remain elusive, as childhood adversity typically co-occurs with detrimental socioeconomic factors, and its impact is likely moderated by biological sex. To unravel the complex relationships among childhood adversity, sex, threat estimation, and alcohol use initiation, we exposed female and male Long-Evans rats to early adolescent adversity (EAA). In adulthood,>50 days following the last adverse experience, threat estimation was assessed using a novel fear discrimination procedure in which cues predict a...
Source: Behavioral Neuroscience - May 28, 2018 Category: Neuroscience Source Type: research
