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This page is alzhub.org's plain-English summary of a published study, not the paper itself. It is generated from the record we hold for this study, sourced and linked below — check the original for the full text and methods.

✓ Peer-reviewed alzhub usefulness score 38 out of 100. Brain scans and imaging

Topic: Brain proteins, microglia and lab models

The neurotrophin hypothesis proposes that repetitive neuronal activity enhances the expression, secretion and actions of neurotrophins to modify synaptic transmission and connectivity thereby providing a connection between neuronal activity and synaptic plasticity. Moreover, there is ample evidence that neurotrophins have numerous neuroprotective effects under pathological conditions, which might be important in particular for neurodegenerative diseases such as Alzheimer' disease. Current research postulates that effects during brain development lead to defective neural connectivity and altered biochemical functioning resulting in cognitive, emotional and intentional dysfunction later in life. This implicates a possible role in most psychiatric diseases including affective and schizophrenic disorders. This hypothesis is mainly based on new experimental evidence showing that psychiatric disorders are associated with neuronal atrophy and cell loss, impairments of structural plasticity and cellular resilience due to neurodevelopmental disturbances and morphological abnormalities of the brain. Thus, the potential role of neurotrophins in psychiatric disorders has been studied in different ways. Animal studies indicate the involvement of neurotrophins in psychopharmacological therapies and they show that gene expression of cerebral neurotrophins is changed in animal models of several psychiatric disorders. Whether such alterations are causatively associated with increased neural plasticity, improved cognitive function and decreased depressive mood states remains to be elucidated in further studies including man (e.g. in postmortem studies of patients). Association studies tried to link different variants in genes coding for neurotrophins, they have not been conclusive however. They partially allow to separate different subgroups of patients with differing therapy response profiles or indicate an increased vulnerability for a specific disorder. Finally, neurotrophin serum changes have been observed in most psychiatric disorders. The question remains though whether these alterations represent primary-causal or secondary-reactive changes.In conclusion, the issue of neuroprotection and neurotrophins is recognised as an important new lead in the quest for a deeper understanding of psychiatric disorders and the mechanisms of action of psychopharmacological interventions.

Key findings

Why it matters

This review discusses the neurotrophin hypothesis, which proposes that neurotrophins link neuronal activity to synaptic plasticity and may have neuroprotective effects relevant to neurodegenerative diseases such as Alzheimer's disease. It is a discussion of a hypothesis and does not show that any treatment, cure or prevention works.

Study details

How this study scored 38/100
How this study's score is builtJournal tier 7 of 10; Journal's citation record 2 of 4; Study design 0 of 12; Strength of evidence 1 of 5; Peer-review validation 10 of 10; How recent 1 of 5; Sample size 0 of 4; Effect reported 0 of 3; Studied in people 0 of 3; Randomised / blinded 0 of 2; Times cited 5 of 7; Citations per year 2 of 5; Impact for its field and year 3 of 6; Cited by studies here 1 of 6; Still being cited 0 of 4; Senior author's track record 3 of 4; Institution's track record 1 of 3; Multi-centre collaboration 0 of 3; Indexed in PubMed 2 of 2; Free to read 0 of 2. Total 38 of 100.38 of 100 points earned62 not earned

Published in a peer-reviewed journal. Scored zero for study design, sample size, effect reported, studied in people and randomised / blinded because the record does not state it.

ComponentPointsWhy
Journal tier 7 / 10 Tier 3 — peer-reviewed journal (Journal of neural transmission (Vienna, Austria : 1996))
Journal's citation record 2 / 4 Journal of Neural Transmission: journal h-index 167 (OpenAlex, 2026-10-29)
Study design 0 / 12 No study design recorded — scores zero, not guessed (not stated in the record — scored 0)
Strength of evidence 1 / 5 Rated “low” in our summary
Peer-review validation 10 / 10 Peer-reviewed. Published as an article in a named peer-reviewed journal.
How recent 1 / 5 2004 — older than 20 years, still counted
Sample size 0 / 4 Participant count not stated — scores zero (not stated in the record — scored 0)
Effect reported 0 / 3 No effect size reported — scores zero (not stated in the record — scored 0)
Studied in people 0 / 3 Not stated whether this was studied in people — scores zero (not stated in the record — scored 0)
Randomised / blinded 0 / 2 No randomisation or blinding stated — scores zero (not stated in the record — scored 0)
Times cited 5 / 7 Cited 116 times (OpenAlex, 2026-10-10)
Citations per year 2 / 5 4.8 citations a year over 24 year(s) since 2004
Impact for its field and year 3 / 6 Cited 3.6× the average for papers of its field and year (OpenAlex FWCI)
Cited by studies here 1 / 6 Cited by 1 other studies in this library
Still being cited 0 / 4 Cited 1 times in 2024–2026 (2026 still in progress; OpenAlex)
Senior author's track record 3 / 4 Last-listed author Rainer Hellweg: h-index 56 (OpenAlex, whole career)
Institution's track record 1 / 3 Charité - Universitätsmedizin Berlin: institution h-index 1,116 (OpenAlex)
Multi-centre collaboration 0 / 3 OpenAlex lists 1 institution(s) in 1 country — scores zero (affiliation lists can be incomplete)
Indexed in PubMed 2 / 2 Indexed in PubMed (PMID 14991461)
Free to read 0 / 2 Behind a paywall — scores zero
Total 38 / 100 —

What each of these 20 components measures, and what this score is not →

Read the original

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Cite this study APA, Vancouver, BibTeX · download .bib or .ris

Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. Check the citation against the original before you use it.

APA 7th

Lang, U. E., Jockers-Scherübl, M. C., & Hellweg, R. (2004). State of the art of the neurotrophin hypothesis in psychiatric disorders: implications and limitations. Journal of neural transmission (Vienna, Austria : 1996). https://doi.org/10.1007/s00702-003-0100-0

Vancouver

Lang UE, Jockers-Scherübl MC, Hellweg R. State of the art of the neurotrophin hypothesis in psychiatric disorders: implications and limitations. Journal of neural transmission (Vienna, Austria : 1996). 2004. doi:10.1007/s00702-003-0100-0. PMID: 14991461.

BibTeX

@article{lang2004-14991461,
  author  = {Lang, U. E. and Jockers-Scherübl, M. C. and Hellweg, R.},
  title   = {{State of the art of the neurotrophin hypothesis in psychiatric disorders: implications and limitations}},
  journal = {Journal of neural transmission (Vienna, Austria : 1996)},
  year    = {2004},
  doi     = {10.1007/s00702-003-0100-0},
  pmid    = {14991461},
  url     = {https://doi.org/10.1007/s00702-003-0100-0}
}

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