G. Hajak

2.2k total citations
37 papers, 1.2k citations indexed

About

G. Hajak is a scholar working on Neurology, Cognitive Neuroscience and Experimental and Cognitive Psychology. According to data from OpenAlex, G. Hajak has authored 37 papers receiving a total of 1.2k indexed citations (citations by other indexed papers that have themselves been cited), including 15 papers in Neurology, 12 papers in Cognitive Neuroscience and 9 papers in Experimental and Cognitive Psychology. Recurrent topics in G. Hajak's work include Transcranial Magnetic Stimulation Studies (12 papers), Sleep and related disorders (6 papers) and Hearing, Cochlea, Tinnitus, Genetics (5 papers). G. Hajak is often cited by papers focused on Transcranial Magnetic Stimulation Studies (12 papers), Sleep and related disorders (6 papers) and Hearing, Cochlea, Tinnitus, Genetics (5 papers). G. Hajak collaborates with scholars based in Germany, Switzerland and Australia. G. Hajak's co-authors include Berthold Langguth, P. Eichhammer, Tobias Kleinjung, Arne May, Thomas Steffens, TC Britton, C. Idzikowski, Derk‐Jan Dijk, Hugh Selsick and Chris Alford and has published in prestigious journals such as American Journal of Psychiatry, Cerebral Cortex and British Journal of Pharmacology.

In The Last Decade

G. Hajak

37 papers receiving 1.2k citations

Peers — A (Enhanced Table)

Peers by citation overlap · career bar shows stage (early→late) cites · hero ref

Name h Career Trend Papers Cites
G. Hajak Germany 13 744 571 311 217 182 37 1.2k
J Grünberger Austria 25 907 1.2× 346 0.6× 141 0.5× 156 0.7× 525 2.9× 163 2.2k
Philippe Hubain Belgium 19 527 0.7× 511 0.9× 68 0.2× 225 1.0× 209 1.1× 54 1.3k
Kenichi Kuriyama Japan 19 799 1.1× 663 1.2× 41 0.1× 230 1.1× 83 0.5× 98 1.4k
Joseph P. Schacht United States 21 712 1.0× 200 0.4× 83 0.3× 75 0.3× 178 1.0× 45 1.9k
Robert Göder Germany 27 1.3k 1.8× 966 1.7× 171 0.5× 443 2.0× 434 2.4× 68 2.2k
Matthew Hughes Australia 23 775 1.0× 221 0.4× 117 0.4× 43 0.2× 303 1.7× 57 1.4k
Stefan Bleich Germany 25 254 0.3× 191 0.3× 118 0.4× 68 0.3× 216 1.2× 71 1.6k
Darragh Downey United Kingdom 20 548 0.7× 399 0.7× 66 0.2× 66 0.3× 219 1.2× 33 1.4k
Bernadette M. Cortese United States 16 280 0.4× 163 0.3× 45 0.1× 47 0.2× 204 1.1× 35 1.0k
Arnd Barocka Germany 17 386 0.5× 531 0.9× 72 0.2× 111 0.5× 425 2.3× 34 1.5k

Countries citing papers authored by G. Hajak

Since Specialization
Citations

This map shows the geographic impact of G. Hajak's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by G. Hajak with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites G. Hajak more than expected).

Fields of papers citing papers by G. Hajak

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by G. Hajak. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by G. Hajak. The network helps show where G. Hajak may publish in the future.

Co-authorship network of co-authors of G. Hajak

This figure shows the co-authorship network connecting the top 25 collaborators of G. Hajak. A scholar is included among the top collaborators of G. Hajak based on the total number of citations received by their joint publications. Widths of edges represent the number of papers authors have co-authored together. Node borders signify the number of papers an author published with G. Hajak. G. Hajak is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

20 of 20 papers shown
1.
Zunhammer, Matthias, P. Eichhammer, Jason R. Franz, G. Hajak, & V Busch. (2012). Effects of acupuncture needle penetration on motor system excitability. Neurophysiologie Clinique. 42(4). 225–230. 11 indexed citations
2.
Wilson, SJ, DJ NUTT, Chris Alford, et al.. (2010). British Association for Psychopharmacology consensus statement on evidence-based treatment of insomnia, parasomnias and circadian rhythm disorders. Journal of Psychopharmacology. 24(11). 1577–1601. 467 indexed citations
3.
Dreiseitel, Andrea, B. Oosterhuis, Peter Schreier, et al.. (2009). Berry anthocyanins and anthocyanidins exhibit distinct affinities for the efflux transporters BCRP and MDR1. British Journal of Pharmacology. 158(8). 1942–1950. 63 indexed citations
4.
Riemann, Dieter & G. Hajak. (2009). Insomnien. Der Nervenarzt. 80(11). 1327–1340. 2 indexed citations
5.
Schmitz, Gerd, et al.. (2009). Frontotemporale Demenz im Zusammenhang mit Familienanamnese Demenz und ApoE-Genotyp. Der Nervenarzt. 81(1). 75–78. 4 indexed citations
6.
Cordes, Joachim, Peter Falkai, Birgit Guse, et al.. (2009). Repetitive transcranial magnetic stimulation for the treatment of negative symptoms in residual schizophrenia: rationale and design of a sham-controlled, randomized multicenter study. European Archives of Psychiatry and Clinical Neuroscience. 259(S2). 189–197. 13 indexed citations
7.
Langguth, Berthold, P. Eichhammer, Marc Zowe, et al.. (2008). Modulating cerebello-thalamocortical pathways by neuronavigated cerebellar repetitive transcranial stimulation (rTMS). Neurophysiologie Clinique. 38(5). 289–295. 34 indexed citations
8.
Langguth, Berthold, Rainer Wiegand, Alexander Kharraz, et al.. (2007). Pre-treatment anterior cingulate activity as a predictor of antidepressant response to repetitive transcranial magnetic stimulation (rTMS).. PubMed. 28(5). 633–8. 55 indexed citations
9.
Eichhammer, P., Tobias Kleinjung, Michael Landgrebe, G. Hajak, & Berthold Langguth. (2007). TMS for treatment of chronic tinnitus — neurobiological effects. Progress in brain research. 166. 369–375. 34 indexed citations
10.
Kleinjung, Tobias, Thomas Steffens, J. Strutz, et al.. (2006). Transkranielle Magnetstimulation zur Behandlung von Tinnitus. HNO. 54(9). 665–666. 7 indexed citations
11.
May, Arne, G. Hajak, Thomas Steffens, et al.. (2006). Structural Brain Alterations following 5 Days of Intervention: Dynamic Aspects of Neuroplasticity. Cerebral Cortex. 17(1). 205–210. 253 indexed citations
12.
Hajak, G., Jörg Marienhagen, Berthold Langguth, et al.. (2004). High-frequency repetitive transcranial magnetic stimulation in schizophrenia: a combined treatment and neuroimaging study. Psychological Medicine. 34(7). 1157–1163. 65 indexed citations
13.
Eichhammer, P., Berthold Langguth, Marc Zowe, & G. Hajak. (2004). Cortical excitability in neuroleptic-naive first-episode schizophrenic patients. Pharmacopsychiatry. 36(5). 2 indexed citations
14.
Eichhammer, P., Alexander Kharraz, Rainer Wiegand, et al.. (2002). Sleep deprivation in depression. Life Sciences. 70(15). 1741–1749. 28 indexed citations
15.
Hajak, G.. (2000). Insomnia in primary care.. PubMed. 23 Suppl 3. S54–63. 36 indexed citations
16.
Adler, L., G. Hajak, K. A. Lehmann, et al.. (1997). On the Problems of Switching from Intravenous to Oral Administration in Drug Treatment of Endogenous Depression. Pharmacopsychiatry. 30(2). 62–69. 6 indexed citations
17.
Staedt, J., et al.. (1995). Schlafstörungen - Was tun, wenn Schlafmittel nicht mehr helfen?. Fortschritte der Neurologie · Psychiatrie. 63(9). 368–372. 3 indexed citations
18.
Bandelow, Borwin, et al.. (1995). Panikstörung und Agoraphobie: Was wirkt?. Fortschritte der Neurologie · Psychiatrie. 63(11). 451–464. 2 indexed citations
19.
Hajak, G., J. Klingelhöfer, M. Schulz-Varszegi, & E. Rüther. (1993). [Blood circulation and energy metabolism of the brain in healthy sleep].. PubMed. 64(7). 456–67. 2 indexed citations
20.
Haase, W., et al.. (1992). Problems in performing a double-blind multicenter study using a hypnotic in private practice.. PubMed. 30(11). 474–474. 2 indexed citations

Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive bibliographic database. While OpenAlex provides broad and valuable coverage of the global research landscape, it—like all bibliographic datasets—has inherent limitations. These include incomplete records, variations in author disambiguation, differences in journal indexing, and delays in data updates. As a result, some metrics and network relationships displayed in Rankless may not fully capture the entirety of a scholar's output or impact.

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