maverickLA
Never get comfortable
Types of aggression
Aggression is a complex phenomenon that is composed of a number of more specific types of behavior. Moyer (1968)[1] presented an early and influential classification of seven different forms of aggression, from a biological and evolutionary point of view.
1. Predatory aggression: attack on prey by a predator.
2. Inter-male aggression: competition between males of the same species over access to resources such as females, dominance, status, etc.
3. Fear-induced aggression: aggression associated with attempts to flee from a threat.
4. Irritable aggression: aggression induced by frustration and directed against an available target.
5. Territorial aggression: defence of a fixed area against intruders, typically conspecifics.
6. Maternal aggression: a female's aggression to protect her offspring from a threat. Paternal aggression also exists.
7. Instrumental aggression: aggression directed towards obtaining some goal, considered to be a learned response to a situation.
Currently, there is a consensus for at least two broad categories of aggression, variously known as hostile, affective, or retaliatory aggression, versus instrumental, predatory, or goal-oriented aggression[2][3][4][5]. Empirical research indicates that this is a critical difference, both psychologically and physiologically. Some research indicates that people with tendencies toward affective aggression have lower IQs than those with tendencies toward predatory aggression [2].
[edit] Biology of aggression
Aggression is directed to and often originates from outside stimuli, but has a very distinct internal character. Using various techniques and experiments, scientists have been able to explore the relationships between various parts of the body and aggression.
[edit] Aggression in the brain
The area from which all emotion originates is the brain. While scientists continue to test various areas of the brain for their effects on aggression, two areas that directly regulate or affect aggression have been found. The amygdala has been shown to be an area that causes aggression. Stimulation of the amygdala results in augmented aggressive behavior [6][7], while lesions of this area greatly reduce one's competitive drive and aggression [8](Bauman et al 2006). Another area, the hypothalamus, is believed to serve a regulatory role in aggression. The hypothalamus has been shown to cause aggressive behavior when electrically stimulated [9] but more importantly has receptors that help determine aggression levels based on their interactions with the neurotransmitters serotonin and vasopressin [10].
[edit] Neurotransmitters and hormones
Various neurotransmitters and hormones have been shown to correlate with aggressive behavior. The most often mentioned of these is the hormone testosterone. Testosterone has been shown to correlate with aggressive behavior in mice and in some humans [11], but in contrast to some long-standing theories, various experiments have not shown a relationship between testosterone levels and aggression in humans [12][13][14]. The possible correlation between testosterone and aggression could explain the "roids rage" that results from anabolic steroid use [15][16].
Another chemical messenger with implications for aggression is the neurotransmitter serotonin. In various experiments, and serotonin was shown to have a negative correlation with aggression [17](Delville et al. 1997). This correlation with aggression helps to explain the aggression-reducing effects of selective serotonin reuptake inhibitors such as fluoxetine (Delville et al. 1997), aka prozac.
While serotonin and testosterone have been the two most researched chemical messengers with regards to aggression, other neurotransmitters and hormones have been shown to relate to aggressive behavior. The neurotransmitter vasopressin causes an increase in aggressive behavior when present in large amounts in the anterior hypothalamus (Delville et al. 1997). The effects of norepinephrine, cortisol, and other neurotransmitters are still being studied.
References
1. ^ Moyer, KE. 1968. Kinds of aggression and their physiological basis. Communications in Behavioral Biology 2A:65-87.
2. ^ a b Behar, D., J. Hunt, A. Ricciuti, D. Stoff, and B. Vitiello. "Subtyping Aggression in Children and Adolescents." The Journal of Neuropsychiatry & Clinical Neurosciences 2 (1990): 189-192. 7 Dec. 2006 <http://neuro.psychiatryonline.org/cgi/content/abstract/2/2/189>.
3. ^ Berkowitz, L. (1993). Aggression: Its causes, consequences, and control. New York, NY: McGraw-Hill.
4. ^ Bushman, B.J. & Anderson, C. A. (2001) Is it time to pull the plug on the hostile versus instrumental aggression dichotomy? Psychological Review 108:273-279.
5. ^ McElliskem, Joseph E. "Affective and Predatory Violence: a Bimodal Classification System of Human Aggression and Violence." Aggression & Violent Behavior 10 (2004): 1-30. 7 Dec. 2006 <http://cat.inist.fr/?aModele=afficheN&cpsidt=16141579>.
6. ^ Decoster, M, M Herbert, J L. Meyerhoff, and M Potegal. "Brief, High-Frequency Stimulation of the Corticomedial Amygdala Induces a Delayed and Prolonged Increase of Aggressiveness in Male Syrian Golden Hamsters." Behavioral Neuroscience 110 (1996): 401-412. 7 Dec. 2006 <http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8731066&dopt=Citation>.
7. ^ Ferris, C F., M Herbert, J Meyerhoff, M Potegal, and L Skaredoff. "Attack Priming in Female Syrian Golden Hamsters is Associated with a C-Fos-Coupled Process Within the Corticomedial Amygdala." Neuroscience 75 (1996): 869-880. 7 Dec. 2006 <http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8951880&dopt=Citation>.
8. ^ Crews, D, N Greenberg, and M Scott. "Role of the Amygdala in the Reproductive and Aggressive Behavior of the Lizard, Anolis Carolinensis." Physiology & Behavior 32 (1984): 147-151.<http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6538977&dopt=Citation>.
9. ^
* Hermans, J, M R. Kruk, A H. Lohman, W Meelis, J Mos, P G. Mostert, and A M. Van Der Poel. "Discriminant Analysis of the Localization of Aggression-Inducing Electrode Placements in the Hypothalamus of Male Rats." Brain Research 260 (1983): 61-79.<http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6681724&dopt=Citation>.
10. ^ Delville, Yvon, Craig F. Ferris, Ray W. Fuler, Gary Koppel, Richard H. Melloni Jr, and Kenneth W. Perry. "Vasopressin/Serotonin Interactions in the Anterior Hypothalamus Control Aggressive Behavior in Golden Hamsters." The Journal of Neuroscience 17 (1997): 4331-4340. 7 Dec. 2006 <http://www.jneurosci.org/cgi/content/abstract/17/11/4331>
11. ^ Gerra, Gilberto, Amir Zaimovic, Paola Avanzini, Beatrice Chittolini, Giuliano Giucastro, Rocco Caccavari, Mariella Palladino, Dante Maestri, Cesare Monica, Roberto Delsignore, and Francesca Brambilla. "Neurotransmitter-Neuroendocrine Responses to Experimentally Induced Aggression in Humans: Influence of Personality Variable." Psychiatry Research 66 (1997): 33-43.<http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TBV-3W3FJMB-4&_coverDate=01%2F15%2F1997&_alid=480296893&_rdoc=1&_fmt=&_orig=search&_qd=1&_cdi=5152&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=30cd1028c2cb69ebf7f2d4662a2aa0d5>.
12. ^ Albert, D.J., M L. Walsh, and R H. Jonik. "Aggression in Humans: What is Its Biological Foundation?" Neuroscience and Biobehavioral Reviews 4 (1993): 405-425.<http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8309650&dopt=Abstract>.
13. ^ Beresford, B., E F. Coccaro, T. Geracioti, J. Kaskow, and P. Minar. "CSF Testosterone: Relationship to Aggression, Impulsivity, and Venturesomeness in Adult Males with Personality Disorder." Journal of Psychiatric Research (2006).<http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=16765987&itool=iconabstr&query_hl=4&itool=pubmed_docsum>.
14. ^ Chandler, D W., J N. Constantino, F J. Earls, D Grosz, R Nandi, and P Saenger. "Testosterone and Aggression in Children." Journal of the American Academy of Child and Adolescent Psychology 32 (1993): 1217-1222.<http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8282667&dopt=Abstract>.
15. ^ Carboni, G, M Nelson, F Pibiri, and Geoffrey Pinna. "Neurosteroids Regulate Mouse Aggression Induced by Anabolic Androgenic Steroids." Neuroreport 17 (2006): 1537-1541.<http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=16957604&query_hl=20&itool=pubmed_docsum>.
16. ^ Choi, P.y. L., D Cowan, and A C. Parrott. "High-Dose Anabolic Steroids in Strength Athletes: Effects Upon Hostility and Aggression." Human Psychopharmacology: Clinical and Experimental 5 (2004): 3497-356.<http://www3.interscience.wiley.com/cgi-bin/abstract/109710653/ABSTRACT>.
17. ^ Cherek, D. R., D. Collins, C. M. Davis, D M. Dougherty, F G. Moeller, and A C. Swann. "Tryptophan Depletion and Aggressive Responding in Healthy Males." Psychopharmacology 126 (1996): 97-103.<http://www.springerlink.com/content/f5k100123937x60x/>.
18. ^ GariepyL., P L. Gendreau, M H. Lewis, D T. Lysle, J M. Petitto, and R Rodriguiz. "Differences in NK Cell Function in Mice Bred for High and Low Aggression: Genetic Linkage Between Complex Behavioral and Immunological Traits?." Brain, Behavior, and Immunity 132 (1999): 175-186.<http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10373280&dopt=Citation>.
19. ^ Buss, D. M. (2005). The murderer next door: Why the mind Is designed to kill. New York: Penguin Press.
20. ^ Tanner, C J. "Numerical Assessment Affects Aggression and Competitive Ability: a Team-Fighting Strategy for the Ant Formica Xerophila." Proceedings. Biological Sciences / the Royal Society (2006).<http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=17015327&query_hl=5&itool=pubmed_docsum>.
So what do you think guys. A lot of talk has been done with steroids and the iimpact they have on aggression. Do you think this is caused by actual chemical changes by your hormones or just due to the fact that you feel stronger and better about yourself - so your aggression can increase because of confidence?
