Stress before training alters memory retrieval of a non-declarative memory in .

Stress alters both memory formation and its retrieval. Here, we show that a combination of stressors before an associative learning event alters memory retrieval of a non-declarative memory in an invertebrate model system. Previously, two combinations of stressors were purported to prevent long-term memory (LTM) formation in 'smart' and this inability to form LTM was considered to be a cost of being smart.

Configural learning: a higher form of learning in .

Events typically occur in a specific context and the ability to assign importance to this occurrence plays a significant role in memory formation and recall. When the scent of a crayfish predator (CE) is encountered in strains known to be predator experienced (e.g.

Green tea and cocoa enhance cognition in .

A flavonoid, (-)-epicatechi (Epi), enhances long-term memory (LTM) formation in and reverses memory obstruction caused by stress. Many foods contain substantial amounts of Epi, (e.g.

Propranolol disrupts consolidation of emotional memory in Lymnaea.

The therapeutic efficacy of the synthetic β-adrenergic receptor blocker, propranolol, for the treatment of post-traumatic stress disorder (PTSD) is currently being debated. Mixed results have been published regarding propranolol's ability to disrupt the consolidation and reconsolidation of memories. Here, we use the invertebrate model Lymnaea to study propranolol's ability to disrupt consolidation of memories formed under varying various types of stress which cause differing degrees of emotional memory.

Strain-specific differences of the effects of stress on memory in .

Stress alters the ability to form, recall and maintain memory according to the Yerkes-Dodson/Hebb (YDH) law. The effects of environmentally relevant stressors, such as low environmental calcium and crowding, on learning and memory have previously been described in a laboratory-reared 'average' strain of (i.e.

Juveniles of Lymnaea 'smart' snails do not perseverate and have the capacity to form LTM.

Previously, it was concluded that the nervous systems of juvenile snails were not capable of mediating long-term memory (LTM). However, exposure and training of those juvenile snails in the presence of a predator cue significantly altered their ability to learn and form LTM. In addition, there are some strains of Lymnaea which have been identified as 'smart'.

Qualitatively different memory states in Lymnaea as shown by differential responses to propranolol.

Mixed results with the synthetic β-adrenergic receptor blocker, propranolol, have been reported in human populations with regards to its therapeutic efficacy for PTSD treatments targeting the memory reconsolidation process. Stress alters the ability to form and maintain memory, but whether the causal neuronal mechanisms underling memory formation in PTSD are similar to normal memory is not clear. Here, we use Lymnaea to study the effects of combinations of stressors on the quality of the formed memory state.

Heat stress enhances LTM formation in Lymnaea: role of HSPs and DNA methylation.

Environmentally relevant stressors alter the memory-forming process in Lymnaea following operant conditioning of aerial respiration. One such stressor is heat. Previously, we found that following a 1 h heat shock, long-term memory (LTM) formation was enhanced.