Cannabinoid inhibition improves memory in food-storing birds, but with a cost.

Food-storing birds demonstrate remarkable memory ability in recalling the locations of thousands of hidden food caches. Although this behaviour requires the hippocampus, its synaptic mechanisms are not understood. Here we show the effects of cannabinoid receptor (CB1-R) blockade on spatial memory in food-storing black-capped chickadees (Poecile atricapilla). Intra-hippocampal infusions of the CB1-R antagonist SR141716A enhanced long-term memory for the location of a hidden food reward, measured 72 h after encoding. However, when the reward location changed during the retention interval, birds that had received SR141716A during initial learning showed impairments in recalling the most recent reward location. Thus, blocking CB1-R activity may lead to more robust, long-lasting memories, but these memories may be a source of proactive interference. The relationship between trace strength and interference may be important in understanding neural mechanisms of hippocampal function in general, as well as understanding the enhanced memory of food-storing birds.

Long-term memory for spatial locations in a food-storing bird (Poecile atricapilla) requires activation of NMDA receptors in the hippocampal formation during learning.

Food-storing birds use a form of long-term memory to recover their hidden food caches that depends on the hippocampal formation (HF). The authors assessed whether food-storing birds' long-term memory for spatial locations requires N-methyl-D-aspartate receptor (NMDA-R)-dependent synaptic plasticity. Black-capped chickadees (Poecile atricapilla) were given bilateral infusions of the NMDA-R antagonist AP5 into the hippocampus, and their memory on a spatial reference memory task was assessed. NMDA-R inactivation during learning prevented formation of long-term spatial memories but did not affect short-term memory and retrieval processes. NMDA-R inactivation immediately following learning did not disrupt long-term memory formation. NMDA-R inactivation disrupted the learning of multiple serially encoded reward locations when a 180-min delay separated successive learning episodes, suggesting that NMDA-R activity has a role in the incorporation of new information into existing long-term memory, as well as in forming unitary long-term memories.

A database of self-reported secondary medical problems among VA spinal cord injury patients: its role in clinical care and management.

An interactive data management (IDM) system for the Spinal Cord Injury (SCI) Service was developed to collect self-reported patient data related to secondary medical complications and to provide feedback to the SCI rehabilitation team. The long-term objective is to improve clinical care through a process of staff review of current rehabilitation programs in the areas of prevalence, prevention, and management. Based on data from the first 99 SCI patients visiting the clinic and hospital after the installation of the IDM system, SCI patients reported high rates of current problems with spasticity (53 percent), pain (44 percent), and pressure ulcers (38 percent). Respiratory (12 percent) and bowel (14 percent) problems were less common current problems. The SCI staff questioned the reportedly high spasticity rates. They thought that the patients' answers might have indicated simply the occurrence of spasticity, rather than the more important issue of severe spasticity that interferes with daily activities. The staff suggested several additional spasticity questions to add to the study. In other areas, only a small percentage of patients wanted to talk with a therapist about prevention of pressure ulcers. Patients who had urinary problems consistently reported five urinary signs (e.g., cloudy urine). The clinical staff found these data informative and stated that they should continue to be collected.