Multisensory Stimulation Improves Cognition and Behavior in Adult Male Rats Born to LT4-treated Thyroidectomized Dams

Abstract

Gestational hypothyroidism can impair development, cognition, and mood. Here we tested whether multisensory stimulation (MS) improves the phenotype of rats born to surgically thyroidectomized (Tx) dams suboptimally treated with LT4. 8-week-old female Tx Wistar rats were kept on daily LT4 (0.7ug/100g BW) dosed by gavage (serum TSH and T4 levels indicated moderate hypothyroidism) and 3 weeks later placed for breeding. MS of the litter started at age 60 days and lasted for 8 weeks. It consisted of twice a week of physical, cognitive, sensorial, and food stimuli. The offspring were assessed before and after MS for standardized tests of locomotor activity, cognition, and mood. Gestational hypothyroidism resulted in reduced litter size and increased offspring mortality. The pups exhibited delayed physical development, impairment of short- and long-term memory, anxiety- and depressive-like behaviors. Nonetheless, ambulatory activity, social memory, and social preference were not affected by gestational hypothyroidism. MS restored short-term memory and anxiety while improving depressive like-behaviors. MS did not improve long-term memory. MS also did not modify the performance of control litter born to intact dams. We conclude that cognition and mood impairments caused by moderate gestational hypothyroidism were reversed or minimized in rats through MS. Further studies should define the molecular mechanisms involved.

Multisensory Stimulation Reverses Memory Impairment in Adrβ3KO Male Mice

“…There is extensive evidence that multisensory stimulation (MS) profoundly affects animal behavior. Specifically, heightened sensory stimulation and problem-solving opportunities enhance performance in various learning and memory tasks [ 12 , 13 , 14 ]. MS encompasses different types of stimuli, such as physical, nutritional, sensorial, cognitive and social [ 15 ].…”

“…MS is known to increase neurogenesis [ 16 , 17 ] and has been shown to improve learning and memory consolidation in several animal models [ 18 , 19 , 20 , 21 , 22 ]. Eight weeks of MS was shown to significantly improve impaired mood and cognition and reduce levels of anxiety and depression in adult male offspring of hypothyroid rat dams [ 12 ]. Three years of music training reversed the reduction in the size of the HC in children with congenital hypothyroidism [ 13 ].…”

Multisensory Stimulation Reverses Memory Impairment in Adrβ3KO Mice

“…There is extensive evidence that multisensory stimulation (MS) profoundly affects animal behavior. Specifically, heightened sensory stimulation and problem-solving opportunities enhance performance on various learning and memory tasks [12][13][14]. MS encompasses different types of stimuli, such as physical, nutritional, sensorial, cognitive, and social [15].…”

“…MS is known to increase neurogenesis [16,17] and has been shown to improve learning and memory consolidation in several animal models [18][19][20][21][22]. Male offspring of hypothyroid rat dams exhibited impaired mood and cognition that persisted during adulthood that were significantly improved after 8 weeks of multisensory stimulation [12]. Anxiety, depression, and impaired cognition in the male offspring of hypothyroid dams were significantly improved after 8 weeks of MS [12].…”

“…Male offspring of hypothyroid rat dams exhibited impaired mood and cognition that persisted during adulthood that were significantly improved after 8 weeks of multisensory stimulation [12]. Anxiety, depression, and impaired cognition in the male offspring of hypothyroid dams were significantly improved after 8 weeks of MS [12]. Music training for approximately 3 years reversed the reduction in the size of the HC in children with congenital hypothyroidism [13].…”