1 00:00:01,920 --> 00:00:06,680 Speaker 1: Welcome to Brainstuff, a production of iHeart Radio Pay brain 2 00:00:06,720 --> 00:00:10,239 Speaker 1: Stuff Lauren bog Obam. Here. When you take your dog 3 00:00:10,280 --> 00:00:12,520 Speaker 1: for a walk, you know you're going to stop at 4 00:00:12,520 --> 00:00:16,400 Speaker 1: every bush, fire, hydrant, mailbox, and any other marked item 5 00:00:16,440 --> 00:00:20,520 Speaker 1: along the route. That's because dogs have highly sensitive sniffers. 6 00:00:20,920 --> 00:00:24,759 Speaker 1: Their noses are constantly processing information left by other neighborhood 7 00:00:24,800 --> 00:00:28,840 Speaker 1: dogs or critters that have passed through their turf. Scientists 8 00:00:28,920 --> 00:00:31,560 Speaker 1: say a dog's sense of smell is ten thousand to 9 00:00:31,640 --> 00:00:35,559 Speaker 1: a hundred thousand times more accurate than humans. Dogs have 10 00:00:35,600 --> 00:00:38,600 Speaker 1: been trained to sniff for bombs at airports, to participate 11 00:00:38,640 --> 00:00:41,840 Speaker 1: in search and rescue, and to even detect certain diseases 12 00:00:41,880 --> 00:00:46,919 Speaker 1: like diabetes and possibly the novel coronavirus. But just like 13 00:00:47,040 --> 00:00:50,440 Speaker 1: any other of the senses, including site, hearing, or taste, 14 00:00:50,960 --> 00:00:54,200 Speaker 1: that sense of smell can disappear for a whole host 15 00:00:54,280 --> 00:00:57,640 Speaker 1: of reasons. If it does, it can be confusing for 16 00:00:57,640 --> 00:01:02,640 Speaker 1: the dog and challenging to diagnose. The loss or the 17 00:01:02,800 --> 00:01:06,319 Speaker 1: decreased ability to smell is called a nasmia, and it's 18 00:01:06,360 --> 00:01:09,959 Speaker 1: a fairly common symptom that people experience with illness or trauma. 19 00:01:10,760 --> 00:01:13,800 Speaker 1: We heard about it most recently during the COVID nineteen pandemic. 20 00:01:14,640 --> 00:01:19,040 Speaker 1: When it happens to people, we usually self report it. Unfortunately, 21 00:01:19,200 --> 00:01:22,520 Speaker 1: dogs can't tell their people what's going on. Instead, they 22 00:01:22,560 --> 00:01:26,960 Speaker 1: may pick up their food or otherwise behave strangely. We 23 00:01:27,040 --> 00:01:30,120 Speaker 1: spoke with Dr Sarah Moore, a veterinarian and professor in 24 00:01:30,160 --> 00:01:33,640 Speaker 1: the College of Veterinary Medicine at the Ohio State University. 25 00:01:33,880 --> 00:01:38,200 Speaker 1: More also specializes in veterinary neurology and neurosurgery, and she 26 00:01:38,280 --> 00:01:40,959 Speaker 1: says that it takes a very astute owner to pick 27 00:01:41,000 --> 00:01:45,000 Speaker 1: up a nasmia in dogs. She said, when we diagnosed 28 00:01:45,080 --> 00:01:48,000 Speaker 1: or documented nasmia in a dog, we're doing it based 29 00:01:48,000 --> 00:01:51,000 Speaker 1: on changes in behavior patterns or things they used to 30 00:01:51,000 --> 00:01:55,040 Speaker 1: do that they can't do anymore. It's quite hard, especially 31 00:01:55,040 --> 00:01:57,280 Speaker 1: if it's just one side of the nose, if they 32 00:01:57,280 --> 00:01:59,520 Speaker 1: can still smell out of the other can be really 33 00:01:59,560 --> 00:02:02,400 Speaker 1: difficult for the owner to realize that there's something wrong. 34 00:02:04,280 --> 00:02:07,600 Speaker 1: Owners typically bring dogs in when it's affected their work, 35 00:02:08,120 --> 00:02:11,240 Speaker 1: for example, a police dog doing scentwork, or dogs the 36 00:02:11,240 --> 00:02:15,520 Speaker 1: airport sniffing for explosives or drugs. More head a case 37 00:02:15,560 --> 00:02:18,160 Speaker 1: of an osmia in a dog that was a bedbug sniffer. 38 00:02:18,840 --> 00:02:21,520 Speaker 1: She said, the dog went to people's houses and smelled 39 00:02:21,520 --> 00:02:24,280 Speaker 1: out bedbugs, and the owners noticed a change in the 40 00:02:24,320 --> 00:02:27,600 Speaker 1: way he did his job. That often triggers the visit 41 00:02:27,639 --> 00:02:30,160 Speaker 1: to the vet, and by then it's usually a complete 42 00:02:30,160 --> 00:02:32,920 Speaker 1: loss of smell because those dogs are so good at 43 00:02:33,000 --> 00:02:38,639 Speaker 1: compensating for any loss of smell. But what causes anosmia? 44 00:02:40,000 --> 00:02:42,880 Speaker 1: More said, the list of concerns is going to include 45 00:02:42,880 --> 00:02:45,080 Speaker 1: things like infections of the lining of the nose or 46 00:02:45,160 --> 00:02:48,600 Speaker 1: chemical irritants. Things that can cause inflammation of the nose lining, 47 00:02:48,840 --> 00:02:52,720 Speaker 1: whether that be infectious or otherwise. Also, problems of the 48 00:02:52,760 --> 00:02:57,080 Speaker 1: brain can actually cause issues with smell. A dog's nose 49 00:02:57,160 --> 00:02:59,640 Speaker 1: and the links between it and its brain are nothing 50 00:02:59,680 --> 00:03:04,359 Speaker 1: short of astonishing for starters. When canines inhale, a fold 51 00:03:04,400 --> 00:03:07,440 Speaker 1: of tissue inside the nostrils separates the air flow into 52 00:03:07,480 --> 00:03:11,200 Speaker 1: two paths, one for old faction and one for respiration. 53 00:03:11,840 --> 00:03:14,600 Speaker 1: About fifteen with the air is sent to the olfactory 54 00:03:14,639 --> 00:03:18,680 Speaker 1: area as it's examined, recognized or not, and sorted before 55 00:03:18,680 --> 00:03:23,560 Speaker 1: it's exhaled. That examination happens in the canine nasal cavity 56 00:03:23,720 --> 00:03:28,760 Speaker 1: or olfactory lobe, positioned directly behind the nose itself. This 57 00:03:28,840 --> 00:03:31,960 Speaker 1: lobe is lined with all kinds of tiny nerve cells 58 00:03:32,000 --> 00:03:35,320 Speaker 1: that connect directly to the brain. Dogs have up to 59 00:03:35,400 --> 00:03:39,280 Speaker 1: three hundred million olfactory receptors depending on the breed, compared 60 00:03:39,280 --> 00:03:43,800 Speaker 1: with only about six million in humans. More said, in dogs, 61 00:03:43,880 --> 00:03:46,760 Speaker 1: the olfactory lobe is massive. If you were to look 62 00:03:46,800 --> 00:03:50,000 Speaker 1: at a dog's olfactory lobe compared to a humans, it's huge. 63 00:03:50,000 --> 00:03:52,600 Speaker 1: In a dog, it's because their sense of smell is 64 00:03:52,640 --> 00:03:55,960 Speaker 1: so highly developed. Problems in that area of the brain 65 00:03:56,120 --> 00:04:00,520 Speaker 1: can cause altered smell, so tumors of the brain, strokes, 66 00:04:00,560 --> 00:04:03,640 Speaker 1: head trauma, injury can all impact the sense of smell. 67 00:04:05,080 --> 00:04:08,720 Speaker 1: That's a long list of potential issues. However, once the 68 00:04:08,800 --> 00:04:12,560 Speaker 1: veterinarian knows what's causing the anosmia, it can usually be treated. 69 00:04:13,240 --> 00:04:16,320 Speaker 1: Sinus infection is typically caused by bacteria and thus treated 70 00:04:16,320 --> 00:04:19,280 Speaker 1: with antibiotics. If the problem is brain related, such as 71 00:04:19,279 --> 00:04:22,040 Speaker 1: a tumor, surgery may be an option, or if they 72 00:04:22,040 --> 00:04:26,400 Speaker 1: can try radiation therapy. The loss of smell is temporary 73 00:04:26,440 --> 00:04:29,680 Speaker 1: when caused by an allergic reaction to medication or exposure 74 00:04:29,720 --> 00:04:32,719 Speaker 1: to chemicals or other irritants, and will usually wear off 75 00:04:32,720 --> 00:04:36,599 Speaker 1: with time, though some loss of smell may linger. However, 76 00:04:37,000 --> 00:04:40,120 Speaker 1: viral infections that cause loss of smell could become permanent 77 00:04:40,240 --> 00:04:45,080 Speaker 1: depending on what virus causes it. More says that questions 78 00:04:45,080 --> 00:04:47,640 Speaker 1: about the link between aging and an osmia in dogs 79 00:04:47,800 --> 00:04:50,719 Speaker 1: are fair because there is some evidence that the condition 80 00:04:50,760 --> 00:04:53,760 Speaker 1: is linked with aging in people, though she has yet 81 00:04:53,800 --> 00:04:56,960 Speaker 1: to see studies done linking the condition to aging in dogs. 82 00:04:58,400 --> 00:05:01,640 Speaker 1: For dogs with viral infections or those that can't otherwise 83 00:05:01,680 --> 00:05:04,279 Speaker 1: be treated, the good news is is that if it's 84 00:05:04,320 --> 00:05:07,080 Speaker 1: just a loss of smell, the dogs usually do pretty 85 00:05:07,080 --> 00:05:09,640 Speaker 1: well with their lot in life, though of course, if 86 00:05:09,640 --> 00:05:12,360 Speaker 1: their job utilizes that sense of smell, they may have 87 00:05:12,400 --> 00:05:16,440 Speaker 1: to retire. And for pups with brain tumors or other 88 00:05:16,480 --> 00:05:21,000 Speaker 1: brain related issues, the result is more complicated and unfortunately 89 00:05:21,200 --> 00:05:25,560 Speaker 1: less cheery. More said, the problem with brain tumors is 90 00:05:25,600 --> 00:05:28,000 Speaker 1: that they do get worse and tend to grow and 91 00:05:28,080 --> 00:05:31,479 Speaker 1: cause other problems. Eventually, there is some palliatee of care 92 00:05:31,520 --> 00:05:34,400 Speaker 1: we can provide. Sometimes we can use steroids to help 93 00:05:34,400 --> 00:05:37,040 Speaker 1: with inflammation around the tumor, and that can be helpful 94 00:05:37,080 --> 00:05:39,279 Speaker 1: for a period of time, but it's not a permanent 95 00:05:39,320 --> 00:05:42,400 Speaker 1: fix from a quality of life standpoint. If they're having 96 00:05:42,440 --> 00:05:44,960 Speaker 1: a lot of other problems, owners might need to consider 97 00:05:45,000 --> 00:05:48,520 Speaker 1: putting their dog to sleep, but More said that is 98 00:05:48,600 --> 00:05:51,520 Speaker 1: definitely a worst case scenario and that in the vast 99 00:05:51,600 --> 00:05:54,520 Speaker 1: majority of dogs, anosmia is a conditioned that will not 100 00:05:54,640 --> 00:05:58,200 Speaker 1: limit a dog's quality of life. She said, while it 101 00:05:58,279 --> 00:06:00,640 Speaker 1: might cause a change in the dogs behave hear, the 102 00:06:00,640 --> 00:06:02,920 Speaker 1: good news is that the most common cause of loss 103 00:06:02,920 --> 00:06:05,680 Speaker 1: of smell and dogs is related to sinus infection, so 104 00:06:05,760 --> 00:06:13,440 Speaker 1: most of those are going to be treatable problems. Today's 105 00:06:13,440 --> 00:06:15,600 Speaker 1: episode was written by Patty res Mussin and produced by 106 00:06:15,640 --> 00:06:18,440 Speaker 1: Tyler Clay. For more on listen lots of other curious topics, 107 00:06:18,520 --> 00:06:21,200 Speaker 1: visit how stuff works dot com. Brain Stuff is production 108 00:06:21,240 --> 00:06:23,640 Speaker 1: of I Heart Radio or more podcasts. My heart Radio 109 00:06:23,760 --> 00:06:26,360 Speaker 1: visit the i heart Radio app, Apple Podcasts, or wherever 110 00:06:26,400 --> 00:06:27,719 Speaker 1: you listen to your favorite shows.