TY - JOUR
T1 - Acute and non-acute Effects of Cannabis on Human Memory Function
T2 - a Critical Review of Neuroimaging Studies
AU - Bossong, Matthijs
AU - Jager, Gerry
AU - Bhattacharyya, Sagnik
AU - Allen, Paul
PY - 2014/4
Y1 - 2014/4
N2 - Smoking cannabis produces a diverse range of effects, including impairments in learning and memory. These effects are exerted through action on the endocannabinoid system, which suggests involvement of this system in human cognition. Learning and memory deficits are core symptoms of psychiatric and neurological disorders such as schizophrenia and Alzheimer's disease, and may also be related to endocannabinoid dysfunction in these disorders. However, before new research can focus on potential treatments that work by manipulating the endocannabinoid system, it needs to be elucidated how this system is involved in symptoms of psychiatric disorders. Here we review neuroimaging studies that investigated acute and non-acute effects of cannabis on human learning and memory function, both in adults and in adolescents. Overall, results of these studies show that cannabis use is associated with a pattern of increased activity and a higher level of deactivation in different memory-related areas. This could reflect either increased neural effort ('neurophysiological inefficiency') or a change in strategy to maintain good task performance. However, the interpretation of these findings is significantly hampered by large differences between study populations in cannabis use in terms of frequency, age of onset, and time that subjects were abstinent from cannabis. Future neuroimaging studies should take these limitations into account, and should focus on the potential of cannabinoid compounds for treatment of cognitive symptoms in psychiatric disorders.
AB - Smoking cannabis produces a diverse range of effects, including impairments in learning and memory. These effects are exerted through action on the endocannabinoid system, which suggests involvement of this system in human cognition. Learning and memory deficits are core symptoms of psychiatric and neurological disorders such as schizophrenia and Alzheimer's disease, and may also be related to endocannabinoid dysfunction in these disorders. However, before new research can focus on potential treatments that work by manipulating the endocannabinoid system, it needs to be elucidated how this system is involved in symptoms of psychiatric disorders. Here we review neuroimaging studies that investigated acute and non-acute effects of cannabis on human learning and memory function, both in adults and in adolescents. Overall, results of these studies show that cannabis use is associated with a pattern of increased activity and a higher level of deactivation in different memory-related areas. This could reflect either increased neural effort ('neurophysiological inefficiency') or a change in strategy to maintain good task performance. However, the interpretation of these findings is significantly hampered by large differences between study populations in cannabis use in terms of frequency, age of onset, and time that subjects were abstinent from cannabis. Future neuroimaging studies should take these limitations into account, and should focus on the potential of cannabinoid compounds for treatment of cognitive symptoms in psychiatric disorders.
KW - Brain function
KW - Cannabis
KW - Cognition
KW - Endocannabinoid system
KW - Memory
KW - Neuroimaging
KW - Psychiatric disorders
KW - δ9-tetrahydrocannabinol (THC)
UR - http://www.scopus.com/inward/record.url?scp=84903700524&partnerID=8YFLogxK
U2 - 10.2174/13816128113199990436
DO - 10.2174/13816128113199990436
M3 - Literature review
C2 - 23829369
AN - SCOPUS:84903700524
SN - 1381-6128
VL - 20
SP - 2114
EP - 2125
JO - Current Pharmaceutical Design
JF - Current Pharmaceutical Design
IS - 13
ER -
