title: Stress inhibits psychomotor performance differently in simple and complex open field environments.
abstract: Stress affects psychomotor profiles and exploratory behavior in response to environmental features. Here we investigated psychomotor and exploratory patterns induced by stress in a simple open-field arena and a complex, multi-featured environment. Groups of rats underwent seven days of restraint stress or no-stress conditions and were individually tested in three versions of the ziggurat task (ZT) that varied according to environmental complexity. The hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis due to stress procedure was evaluated by the pre- and post-stress levels of circulating corticosterone (CORT). Horizontal activity, exploration, and motivation were measured by the number of fields entered, the time spent in the central fields, path length and speed, and stop duration. In addition, vertical exploratory behavior was measured by the times rats climbed onto ziggurats. Stress-induced psychomotor changes were indicated by reduced path length and path speed and increased duration of stops only within the complex arena of the ZT. Rats in stress groups also showed a significant decline in the vertical movements as measured by the number of climbing onto ziggurats. No stress-induced changes were revealed by the simple open-field arena. The exploratory patterns of stressed animals suggest psychomotor inhibition and reduced novelty-seeking behaviors in an environment-dependent manner. Thus, multi-featured arenas that require complex behavioral strategies are ideally suited to reveal the inhibitory effects of stress on psychomotor capabilities in rodents.
authors: Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB, Canada; Golestan University of Medical Sciences, Faculty of Nursing & Midwifery, Gorgan, Islamic Republic of Iran. Electronic address: jamshid.faraji@uleth.ca.
authors: Jamshid
authors: J
authors: Faraji
authors: Department of Anatomy, Biology and Molecular Research Center, Babol University of Medical Sciences, Babol, Islamic Republic of Iran.
authors: Nabiollah
authors: N
authors: Soltanpour
authors: Golestan University of Medical Sciences, Faculty of Nursing & Midwifery, Gorgan, Islamic Republic of Iran.
authors: Seyed Yaghoob
authors: SY
authors: Jafari
authors: Avicenna Institute of Neuroscience, Department of Behavioural Studies, Yazd, Islamic Republic of Iran.
authors: Reza
authors: R
authors: Moeeini
authors: Avicenna Institute of Neuroscience, Department of Behavioural Studies, Yazd, Islamic Republic of Iran.
authors: Shiva
authors: S
authors: Pakdel
authors: Golestan University of Medical Sciences, Department of Anatomy, Gorgan, Islamic Republic of Iran.
authors: Alireza
authors: A
authors: Moharreri
authors: Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB, Canada.
authors: Gerlinde A S
authors: GA
authors: Metz
mesh_terms: D000818:Animals; D004777:Environment; D005106:Exploratory Behavior / Q000502:physiology; D006854:Hydrocortisone / Q000097:blood; D008297:Male; D009042:Motivation; D009043:Motor Activity / Q000502:physiology; D011597:Psychomotor Performance / Q000502:physiology*; D051381:Rats; D020318:Rats, Long-Evans; D012149:Restraint, Physical; D013315:Stress, Psychological / Q000523:psychology*
chemical_list: D006854:Hydrocortisone
keywords: Corticosterone; Environment; Exploration; Motor behavior; Novelty-seeking; Open field; Restraint stress; Ziggurat task