Influence of environmental stimulation on neurogenesis in the adult insect brain

Abstract

Mushroom bodies are the main integrative structures of insect brain. They receive sensory information from the eyes, the palps, and the antennae. In the house cricket, Acheta domesticus, a cluster of mushroom body neuroblasts keeps producing new interneurons during an insect's life span. The aim of the present work is to study the impact of environmental stimuli on mushroom body neurogenesis during adulthood. Crickets were reared either in an enriched environment, where they received complex environmental and congeneric stimulations or isolated in small cages and deprived of most visual, auditory, and olfactory stimuli. They then were injected with a S‐phase marker, 5‐bromo, 2′‐deoxyuridine (BrdU) and sacrificed at different periods of their life. Neurogenesis and cell survival were estimated by counting the number of BrdU‐labeled cells in the mushroom bodies. Environmentally enriched crickets were found to have an increased number of newborn cells in their mushroom bodies compared with crickets housed in cages with an impoverished environment. This effect of external factors on neurogenesis seems to be limited to the beginning of imaginal life. Furthermore, no cell loss could be detected among the newborn neurons in either environmental situation, suggesting that cell survival was not affected by the quality of the environment. Considering vertebrate studies which showed that enriched environment increases hippocampal cell survival and improves animal performances in spatial learning tests, we suggest that the increased number of interneurons produced in an integrative brain structure after exposure to enriched environment could contribute to adaptive behavioral performances in adult insects. © 2000 John Wiley & Sons, Inc. J Neurobiol 45: 162–171, 2000

Environmental enrichment and prior experience of live prey improve foraging behaviour in hatchery‐reared Atlantic salmon

“…There is no evidence of an independent effect of prior exposure to live prey. Overall these results are consistent with the recent results from rats and crickets (Park et al, 1992;Gomez-Pinilla et al, 1998;Lomassese et al, 2000Lomassese et al, , 2002 and support the idea that exposure to enriched environments provides increased neural plasticity resulting in improvements in learning ability and behavioural flexibility. It now appears that this process is almost certainly universal amongst all animals (mammals: Gage et al, 1998;birds: Alvarez-Buylla, 1990;insects: Lomassese et al, 2000insects: Lomassese et al, , 2002 and expels the long held belief that brain development ceases long before adulthood (Altman, 1962).…”

Environmental enrichment and prior experience of live prey improve foraging behaviour in hatchery‐reared Atlantic salmon

“…There is no evidence of an independent effect of prior exposure to live prey. Overall these results are consistent with the recent results from rats and crickets (Park et al, 1992;Gomez-Pinilla et al, 1998;Lomassese et al, 2000Lomassese et al, , 2002 and support the idea that exposure to enriched environments provides increased neural plasticity resulting in improvements in learning ability and behavioural flexibility. It now appears that this process is almost certainly universal amongst all animals (mammals: Gage et al, 1998;birds: Alvarez-Buylla, 1990;insects: Lomassese et al, 2000insects: Lomassese et al, , 2002 and expels the long held belief that brain development ceases long before adulthood (Altman, 1962).…”

Environmental Enrichment Increases Brain Volume in Snakes

“…Various species of turtles also display an increase in the diversity of behaviors when exposed to EE in the form of larger space and more stimuli (Turner et al 2022). The increased level of exercise available to snakes in the enriched condition may have been partially responsible for their larger brain volume, consistent with findings in other taxa (Cummins et al 1973;Scotto Lomassese et al 2000;Fong et al 2019;Näslund et al 2012).…”

The Colony Environment, but Not Direct Contact with Conspecifics, Influences the Development of Circadian Rhythms in Honey Bees

“…Similar to our findings, the influence of the colony environment was evident also in bees that were prevented from direct contact with other bees by a double-mesh enclosure (Ichikawa and Sasaki, 2003). In a broader perspective, these findings for bees fit well with studies showing that social isolation has strong effects on the development of brain and behavior in both vertebrates and invertebrates (e.g., Fone and Porkess, 2008; Hall, 1998; Harlow, 1965; Heisenberg et al, 1995; Scotto Lomassese et al, 2000; Technau, 2007).…”

Environmental enrichment and prior experience of live prey improve foraging behaviour in hatchery‐reared Atlantic salmon

“…There is no evidence of an independent effect of prior exposure to live prey. Overall these results are consistent with the recent results from rats and crickets (Park et al, 1992;Gomez-Pinilla et al, 1998;Lomassese et al, 2000Lomassese et al, , 2002 and support the idea that exposure to enriched environments provides increased neural plasticity resulting in improvements in learning ability and behavioural flexibility. It now appears that this process is almost certainly universal amongst all animals (mammals: Gage et al, 1998;birds: Alvarez-Buylla, 1990;insects: Lomassese et al, 2000insects: Lomassese et al, , 2002 and expels the long held belief that brain development ceases long before adulthood (Altman, 1962).…”

Environmental Enrichment Increases Brain Volume in Snakes

“…Various species of turtles also display an increase in the diversity of behaviors when exposed to EE in the form of larger space and more stimuli (Turner et al 2022). The increased level of exercise available to snakes in the enriched condition may have been partially responsible for their larger brain volume, consistent with findings in other taxa (Cummins et al 1973;Scotto Lomassese et al 2000;Fong et al 2019;Näslund et al 2012).…”

The Colony Environment, but Not Direct Contact with Conspecifics, Influences the Development of Circadian Rhythms in Honey Bees

“…Similar to our findings, the influence of the colony environment was evident also in bees that were prevented from direct contact with other bees by a double-mesh enclosure (Ichikawa and Sasaki, 2003). In a broader perspective, these findings for bees fit well with studies showing that social isolation has strong effects on the development of brain and behavior in both vertebrates and invertebrates (e.g., Fone and Porkess, 2008; Hall, 1998; Harlow, 1965; Heisenberg et al, 1995; Scotto Lomassese et al, 2000; Technau, 2007).…”

Environmental enrichment and prior experience of live prey improve foraging behaviour in hatchery‐reared Atlantic salmon

“…There is no evidence of an independent effect of prior exposure to live prey. Overall these results are consistent with the recent results from rats and crickets (Park et al, 1992;Gomez-Pinilla et al, 1998;Lomassese et al, 2000Lomassese et al, , 2002 and support the idea that exposure to enriched environments provides increased neural plasticity resulting in improvements in learning ability and behavioural flexibility. It now appears that this process is almost certainly universal amongst all animals (mammals: Gage et al, 1998;birds: Alvarez-Buylla, 1990;insects: Lomassese et al, 2000insects: Lomassese et al, , 2002 and expels the long held belief that brain development ceases long before adulthood (Altman, 1962).…”

Environmental Enrichment Increases Brain Volume in Snakes

“…Various species of turtles also display an increase in the diversity of behaviors when exposed to EE in the form of larger space and more stimuli (Turner et al 2022). The increased level of exercise available to snakes in the enriched condition may have been partially responsible for their larger brain volume, consistent with findings in other taxa (Cummins et al 1973;Scotto Lomassese et al 2000;Fong et al 2019;Näslund et al 2012).…”

The Colony Environment, but Not Direct Contact with Conspecifics, Influences the Development of Circadian Rhythms in Honey Bees

“…Similar to our findings, the influence of the colony environment was evident also in bees that were prevented from direct contact with other bees by a double-mesh enclosure (Ichikawa and Sasaki, 2003). In a broader perspective, these findings for bees fit well with studies showing that social isolation has strong effects on the development of brain and behavior in both vertebrates and invertebrates (e.g., Fone and Porkess, 2008; Hall, 1998; Harlow, 1965; Heisenberg et al, 1995; Scotto Lomassese et al, 2000; Technau, 2007).…”