Overall, results propose that LIP relies on neuronal pattern separation to facilitate decision-relevant discrimination of sensory stimuli. This hypothesis suggests that LIP alters the representation of ambiguous inputs to reduce their overlap, thus improving sensory discrimination. A combination of computational modeling, theoretical analysis, and electrophysiological data shows that the pattern separation hypothesis links neural activity to behavior and offers novel predictions on the role of LIP during sensory discrimination.
The medial nucleus of the trapezoid body MNTB is an important source of inhibition during the computation of sound location. It transmits fast and precisely timed action potentials at high frequencies; this requires an efficient calcium clearance mechanism, in which plasma membrane calcium ATPase 2 PMCA2 is a key component. The MNTB tonotopic axis encodes high to low sound frequencies across the medial to lateral dimension. We discovered a cell size gradient along this axis: lateral neuronal somata are significantly larger than medially located somata.
The lack of acoustically driven input suggests that sound-evoked activity is required for maintenance of the cell size gradient. This hypothesis was corroborated by selective elimination of auditory hair cell activity with either hair cell elimination in Pou4f3 DTR mice or inner ear tetrodotoxin TTX treatment.
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The change in soma size was reversible and recovered within 7 days of TTX treatment, suggesting that regulation of the gradient is dependent on synaptic activity and that these changes are plastic rather than permanent. The MNTB is topographically organized, with low sound frequencies encoded laterally and high frequencies medially.
We discovered a cell size gradient along this axis: lateral neurons are larger than medial neurons. The absence of this gradient in deaf mice lacking plasma membrane calcium ATPase 2 suggests an activity-dependent, calcium-mediated mechanism that controls neuronal soma size.
Intraspinal microstimulation ISMS using implanted electrodes can evoke locomotor movements after spinal cord injury SCI but has not been explored in the context of respiratory motor output. An advantage over epidural and direct muscle stimulation is the potential of ISMS to selectively stimulate components of the spinal respiratory network. The present study tested the hypothesis that medullary respiratory activity could be used to trigger midcervical ISMS and diaphragm motor unit activation in rats with cervical SCI.
Studies were conducted after acute hours and subacute 5—21 days C 2 hemisection C2Hx injury in adult rats. After both acute and subacute injury, genioglossus EMG activity effectively triggered ISMS and activated diaphragm motor units during the inspiratory phase. The ISMS paradigm also evoked short-term potentiation of spontaneous inspiratory activity in the previously paralyzed hemidiaphragm i.
This proof-of-concept study demonstrated the efficacy of diaphragm activation, using an upper airway respiratory EMG signal to trigger ISMS at the level of the ipsilesional phrenic nucleus during acute and advanced postinjury intervals. The aim of this study was to test the effects of a concurrent cognitive task on the promptness of the sensorimotor integration and reweighting processes following addition and withdrawal of vision. Fourteen subjects stood in tandem while vision was passively added and removed. We also estimated the time constant of the exponential change in body oscillation until the new level of sway was reached, consistent with the current visual state.
Under the mentally idle condition, mean latency was 0. Following addition of vision, counting backward delayed the latency by about ms, without affecting the time constant. Following withdrawal, counting backward had no significant effect on either latency or time constant.
The extension by counting backward of the time interval to stabilization onset on addition of vision suggests a competition for allocation of cortical resources. Conversely, the absence of cognitive task effect on the rapid onset of destabilization on vision withdrawal, and on the relevant reweighting time course, advocates the intervention of a subcortical process.
Diverting attention from a challenging standing task discloses a cortical supervision on the process of sensorimotor integration of new balance-stabilizing information. A subcortical process would instead organize the response to removal of the stabilizing sensory input. Performing such a cognitive task increases the time delay following addition of vision but has no effect on withdrawal dynamics. The translation of brief, millisecond-long pain-eliciting stimuli to the subjective perception of pain is associated with changes in theta, alpha, beta, and gamma oscillations over sensorimotor cortex.
However, when a pain-eliciting stimulus continues for minutes, regions beyond the sensorimotor cortex, such as the prefrontal cortex, are also engaged. Abnormalities in prefrontal cortex have been associated with chronic pain states, but conventional, millisecond-long EEG paradigms do not engage prefrontal regions. In the current study, we collected high-density EEG data during an experimental paradigm in which subjects experienced a 4-s, low- or high-intensity pain-eliciting stimulus. EEG data were analyzed using independent component analyses, EEG source localization analyses, and measure projection analyses.
We report three novel findings. First, an increase in pain perception was associated with an increase in gamma and theta power in a cortical region that included medial prefrontal cortex. Second, a decrease in lower beta power was associated with an increase in pain perception in a cortical region that included the contralateral sensorimotor cortex. Third, we used machine learning for automated classification of EEG data into low- and high-pain classes. Theta and gamma power in the medial prefrontal region and lower beta power in the contralateral sensorimotor region served as features for classification.
We found a leave-one-out cross-validation accuracy of The development of biological markers for pain states continues to gain traction in the literature, and our findings provide new information that advances this body of work.
Our approach represents a novel neurophysiological paradigm that advances the literature on biological markers for pain. Presynaptic inhibition of the sensory input from the periphery to the spinal cord can be evaluated directly by intra-axonal recording of primary afferent depolarization PAD or indirectly by intraspinal microstimulation excitability testing. Excitability testing is superior for use in normal behaving animals, because this methodology bypasses the technically challenging intra-axonal recording.
However, use of excitability testing on the muscle or joint afferent in intact animals presents its own technical challenges. Because these afferents, in many cases, are mixed with motor axons in the peripheral nervous system, it is crucial to dissociate antidromic volleys in the primary afferents from orthodromic volleys in the motor axon, both of which are evoked by intraspinal microstimulation. We have demonstrated in rats that application of a paired stimulation protocol with a short interstimulus interval ISI successfully dissociated the antidromic volley in the nerve innervating the medial gastrocnemius muscle.
By using a 2-ms ISI, the amplitude of the volleys evoked by the second stimulation was decreased in dorsal root-sectioned rats, but the amplitude did not change or was slightly increased in ventral root-sectioned rats. Excitability testing in rats with intact spinal roots indicated that the putative antidromic volleys exhibited dominant primary afferent depolarization, which was reasonably induced from the more dorsal side of the spinal cord. We concluded that excitability testing with a paired-pulse protocol can be used for studying presynaptic inhibition of somatosensory afferents in animals with intact spinal roots.
However, to apply this method to muscle afferents of animals with intact spinal roots, it is crucial to dissociate antidromic and orthodromic volleys induced by spinal microstimulation. We propose a new method to make this dissociation possible without cutting spinal roots and demonstrate that it facilitates excitability testing of muscle afferents.
Humans maintain a stable representation of the visual world effortlessly, despite constant movements of the eyes, head, and body, across multiple planes. Whereas visual stability in the face of saccadic eye movements has been intensely researched, fewer studies have investigated retinal image transformations induced by head movements, especially in the frontal plane. Unlike head rotations in the horizontal and sagittal planes, tilting the head in the frontal plane is only partially counteracted by torsional eye movements and consequently induces a distortion of the retinal image to which we seem to be completely oblivious.
One possible mechanism aiding perceptual stability is an active reconstruction of a spatiotopic map of the visual world, anchored in allocentric coordinates. The aftereffect was shown to have both a retinotopic and spatiotopic component. When tested with unpatterned Gaussian blobs rather than sinusoidal grating stimuli, the retinotopic component was greatly reduced, whereas the spatiotopic component remained.
The results suggest that perceptual stability may be maintained at least partially through mechanisms involving spatiotopic coding. To this end, we measure the strength of the positional motion aftereffect PMAE; previously shown to be largely spatiotopic after saccades after large head tilts. We find that, as with eye movements, the spatial selectivity of the PMAE has a large spatiotopic component after head rotation. Multivariate pattern analysis of functional magnetic resonance imaging fMRI data is widely used, yet the spatial scales and origin of neurovascular signals underlying such analyses remain unclear.
We compared decoding performance for stimulus orientation and eye of origin from fMRI measurements in human visual cortex with predictions based on the columnar organization of each feature and estimated the spatial scales of patterns driving decoding. Both orientation and eye of origin could be decoded significantly above chance in early visual areas V1—V3. Contrary to predictions based on a columnar origin of response biases, decoding performance for eye of origin in V2 and V3 was not significantly lower than that in V1, nor did decoding performance for orientation and eye of origin differ significantly.
Instead, response biases for both features showed large-scale organization, evident as a radial bias for orientation, and a nasotemporal bias for eye preference. To determine whether these patterns could drive classification, we quantified the effect on classification performance of binning voxels according to visual field position.
Consistent with large-scale biases driving classification, binning by polar angle yielded significantly better decoding performance for orientation than random binning in V1—V3. Similarly, binning by hemifield significantly improved decoding performance for eye of origin. Patterns of orientation and eye preference bias in V2 and V3 showed a substantial degree of spatial correlation with the corresponding patterns in V1, suggesting that response biases in these areas originate in V1. Together, these findings indicate that multivariate classification results need not reflect the underlying columnar organization of neuronal response selectivities in early visual areas.
For eye of origin this pattern is a nasotemporal bias; for orientation it is a radial bias. Differences in decoding performance across areas and stimulus features are not well predicted by differences in columnar-scale organization of each feature. Large-scale biases in extrastriate areas are spatially correlated with those in V1, suggesting biases originate in primary visual cortex. Phrenic motor facilitation pMF , a form of respiratory plasticity, can be elicited by acute intermittent hypoxia i.
Our results give insights concerning the differential impact of systemic inflammation and the functional significance of multiple cascades capable of giving rise to phrenic motor plasticity. Small-amplitude, higher frequency oscillations of the body or limb are typically observed when humans attempt to maintain the position of a body or limb in space.
Recent investigations have suggested that these involuntary movements of the body during stance could be used as an exploratory means of acquiring sensory information. In the present study, we wanted to determine whether a similar phenomenon would be observed in an upper limb postural task that does not involve whole body postural control. Participants were placed in a supine position with the arm pointing vertically and were asked to maintain the position of the limb in space with and without visual feedback. From unlocked to locked, angular accelerations increased in the eyes-closed condition and when participants were provided visual feedback of arm angular displacements.
Irrespective of their origin, small displacements of the limb may be used as an exploratory means of acquiring sensory information from the surrounding environment. We tested whether variability remains in the absence of sensory-based error with an apparatus that stabilized the limb without the participant's knowledge during a static postural task.
Increased forces observed during arm stabilization predicted movements greater than those observed when not externally stabilized. These results suggest movement variability during static postures could facilitate the gathering of sensory information from the surrounding environment. Auditory signals that contain coherent level fluctuations of a masker in different frequency regions enhance the detectability of an embedded sinusoidal target signal, an effect commonly known as comodulation masking release CMR. Neural correlates have been proposed at different stages of the auditory system.
While later stages seem to suppress the response to the masker, earlier stages are more likely to enhance their response to the signal when the masker is comodulated. Using a flanking band masking paradigm, the present study investigates how CMR is represented at the level of the inferior colliculus of the Mongolian gerbil. The responses to a target signal at various sound pressure levels in three different masking conditions were compared. In one condition the masker was a Hz amplitude modulated sinusoid centered at the signal frequency while in the other two conditions six off-frequency carriers flanking bands were added.
For 64 of a total of 94 units, the addition of comodulated flanking bands to the on-frequency masker did not change the response to the target signal. The remaining 30 units showed a change that enhanced target detectability if coherent flanking bands were added, indicative of CMR. The current data demonstrate that the response characteristics of these neurons represent an intermediate stage between the representation in the cochlear nucleus and the auditory cortex by increasing the response during the signal intervals and decreasing the response for the following masker portions.
In this study, we demonstrate how the representation of a signal in comodulated masking conditions changes along the auditory pathway by using a stimulus paradigm from the cochlea nucleus for the first time in the inferior colliculus. This happens on a timescale that makes corticocollicular feedback a likely candidate as the source. Horizontal cells HCs are inhibitory interneurons of the vertebrate retina. HCs are especially well characterized in teleost fish and have been used to unlock mysteries of the vertebrate retina for over one century. More recently, mammalian models of the retina have been increasingly informative for HC physiology.
Special attention is given to interactions between ion channels, to differences among species, and in which subtypes of HCs these channels have been found. Standing balance is significantly influenced by postural threat. While this effect has been well established, the underlying mechanisms of the effect are less understood. The involvement of the vestibular system is under current debate, and recent studies that investigated the effects of height-induced postural threat on vestibular-evoked responses provide conflicting results based on kinetic Horslen BC, Dakin CJ, Inglis JT, Blouin JS, Carpenter MG.
Eur J Neurosci —, data. We examined the effect of threat of perturbation, a different form of postural threat, on coupling cross-correlation, coherence, and gain of the vestibulo-muscular relationship in 25 participants who maintained standing balance. Quiet standing immediately before the surface tilts was compared to an equivalent time from the No-Threat conditions.
Surface EMG was recorded from bilateral trunk, hip, and leg muscles. Hip and leg muscles exhibited significant increases in peak cross-correlation amplitudes, coherence, and gain 1. These findings show a clear threat effect on vestibular-evoked responses in muscles in the lower body, with less robust effects of threat on trunk muscles. Combined with previous work, the present results can provide insight into observed changes during balance control in threatening situations.
While robust findings were observed in hip and leg muscles, less consistent results were found in muscles of the trunk. The present findings provide further support in the ongoing debate for arguments that vestibular-evoked balance responses are influenced by fear and anxiety and explain previous threat-related changes in balance. Journal home Ahead of Print Issues. Archive of all online content. January July Articles in Press. Volume Issue 1. Volume Issue 6. Volume Issue 5. Volume Issue 4.
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Volume Issue 2 Feb pages View large image. Journal of Neurophysiology Feb Cover : Electrophysiological and morphological measurements were obtained simultaneously from a single corticospinal neuron. Neuro Forum Free Access. Pathophysiology of affective disorders: functional interaction of stress hormones and hippocampal excitation M. Adrienne McGinn and Amanda R. Abstract Full text PDF References Preview Abstract An important new study by Kvarta, Bradbrook, Dantrassy, Bailey, and Thompson J Neurophysiol —, examined the effects of persistent stress and excessive glucocorticoid levels on hippocampal function and emotional behavior in rodents.
Free Access. Foot placement relies on state estimation during visually guided walking Rodrigo S. Maeda, Shawn M. O'Connor, J. Maxwell Donelan, and Daniel S. Abstract Full text PDF References Preview Abstract As we walk, we must accurately place our feet to stabilize our motion and to navigate our environment. Contrast sensitivity, V1 neural activity, and natural vision James E. Niemeyer and Michael A. Abstract Full text PDF References Preview Abstract Contrast sensitivity is fundamental to natural visual processing and an important tool for characterizing both visual function and clinical disorders.
Gransee, Carlos B. Abstract Full text PDF References Preview Abstract Unilateral C 2 cervical spinal cord hemisection SH disrupts descending excitatory drive to phrenic motor neurons, thereby paralyzing the ipsilateral diaphragm muscle DIAm during ventilatory behaviors. The other parties will ignore this possibility at their peril.
At this rate the whole of Europe will soon be far-right and will be walking in jackboots over any country not keen on joining the EU. Anyway, back to the story. I carried on with emails until just gone About midday I had a text on my new phone from Yvonne asking if they could call in and take me for lunch no prize for guessing where and I said fine as long as I could treat them. Once back I made sure the messages were up to date.
Ugo et al arrived about 1. I was prepared and wasted no time in going out to the car. I pulled my tongue out at Reuben a couple of times much to his delight and got in. Fifteen minutes later we were there. It was crowded again but miraculously my chairs were free. Angie had her hands full but found time to say hello.
Tariq was playing waiter again and was also busy but still found time to say hello to everyone. We all ordered and I settled on a chocolate milkshake and a quarter pounder with chunky chips. It was all great though Reuben felt the floor needed decorating by his. Those feet come down with a wallop. Before we left I got to the counter first and gave Tariq far too much money so I could accept some change but still leave enough for the meal. Then I had to face a barrage from Yvonne about not letting them pay.
We drove home, I had time to pass Yvonne a bag of things I had for her and Ugo before they had to leave so he could work at home. I spent an age getting up to date again before relaxing for a while in the lounge. It was a 4. I came round again about 9. I stayed on the bed relaxing for a while before going through to apologise to the fish and ask them to blow bubbles quietly, take my meds and bring a coffee through to finish the emails off.
When I got back I sat in the lounge with a drink and just fell asleep till lunchtime. Lunch over I managed to clear a few more messages before plonking myself in front of a Homes in the Country and falling straight back to sleep. When I woke up it was to a knock on the door as the chemist delivered a fresh lot of goodies to make me high, low, sugar free or whatever else they do. I watched my antiques programme and then a couple of quizzes, had a little tea to take my second set of food tabs and watched another Antiques Road Trip.
Tonight one of the two experts was an auctioneer I just cannot get on with. He may be one of the nicest people around but his mannerisms are most annoying. Fortunately his opponent was another auctioneer who is a really nice person and a perfect gentleman and their team members were divided the same way so I had no problem egging the nice side on to win…which they did.
I envy them the amount of time they get to spend with antiques, especially art nouveau pieces. I had one and a half hours back on the computer while I watched the season finale of The Mentalist which was not as absorbing as usual. I did nothing of any interest during the day bar sleep and catch up on emails. Lee arrived at about 5. They missed it, arriving at 6. The traffic had been bad it seemed. I made the drinks. Lee and I already had our drinks.
We had two games of scrabble of which I won the first Thanks Elaine for xu and za and Matt won the second. I had to leave the room for a minute and when I returned a decision had been made that we play Balderdash next, my heart soared only to come down to earth with a thus when I was told it was Absolute Balderdash they wanted. Matt ran away with the game tonight. I just seemed to choose his answers constantly. Lee had to leave after that game probably before I killed him so the three of us had our usual game of Nomination Whist at which I excelled tonight.
I confess it was sheer luck but who cares how you reach the end as long as you do. I always wonder how Dil can thank me before he leaves after a win like that. We packed up and they left me to wash the pots and tidy up before heading for the computer to catch up on all the outstanding mail and this blog.
I still might make it to bed before midnight though. It was a funny old night. I managed to get to bed by midnight-just, but wanted to have a read to relax. I turned the light off at I remember seeing 1. This truly awful noise of a bagpipe playing Scotsman being strangled woke me up. It was 2. I nodded off again only for the birds to start their chorus at the ungodly time of 4. They just laughed at my attempts to have another hissy fit.
I was half tempted to give up and start work but I knrw I needed more sleep yet so when the little beggars paused to take a breath I put a pillow over my head and nodded off until 6. I visited the loo then came back and turned the computer on. I emptied my ash tray and lit my first of the morning as I started the mail.
I broke off at 7. So, I fed the fish thinking what a shame I no longer have Big Bill to come greet me. I had my meds then some breakfast and took a coffee back to the messages. There were quite a few to do but there was no rush. My weekly dose of hope. I want a really nice win in order to take a holiday. Back at home the postman called and brought me some stylus pens to use on the new to me touch phone. I worked until just before Within moments I was well away and only woke when I let rip a real snort which scared the life out of me and the window cleaner both.
After all, who sleeps at that time of day. It was time to make some lunch. I decided to settle on pizza and micro chips today. A strawberry yoghurt to follow and I was a happy man. I washed the pots and watched half my antiques programme before going back to the mail. I had a happy time in here until 4.
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See you later. Still, I can go to bed now. The cat must have decided no to face the big snake again and allowed me to sleep this morning until 5. When I did wake there was the sound of birds and the lack of a sound of rain. Perhaps a little early for me to expect sunshine though. After nipping to the loo I turned on the computer and went straight to the forecast. Possible light showers, but for the weekend- sunshine and warmth. I can cope with that. At I had at least got dressed. At midday I had a ham bap for lunch with a packet small of cheddars.
I went through to keep as up to date as possible before he arrived. That event happened at 1. Mike had said he was due to finish at 4. When we arrived at 2. Mike said I had it. I did a little more mail then we watched an Antique Road Trip. I guessed he was probably peckish by then so I made him a meal of new potatoes, lamb shank and petit pois. For some reason we sat chatting and half watching TV until 9. I reached a point where I thought I could risk a short break and while Mike was watching football and went to take a shower.
Before I did Mike broke off from the game kindly I thought as full time had been called and washed my hair. After the shower I came through to get into my lounge lizard pants and a t-shirt and take up where I left off. So I bis you all goodnight and sweet dreams. Look, if you must have a cup of tea get it now. First job turn the light on the fish tank, then turn the kettle on. That had chance to start boiling while I dealt with the chemist shop before me. I went to check. His eyes were open and he was carrying his coffee. He was even wearing clothes so as not to scare the horses.
Perhaps I should have included the car in the discussion as it headed straight for Broughton Park. We managed to knock a fair few things off the list and headed for the tills. We loaded the conveyor, Mike in his OCD lines and me in my more haphazard way of heaviest to the front, lightest to the back. He agreed. I stood by the door for an age till I saw him outside enjoying a cigarette. I left him to finish the ciggie and follow me upstairs which he did and shot past me saying he was headed for the loo.
I headed for the cafe to order the drinks. No joy there either. From there we headed for Flint to restock my ice lollies, the pizzas and the micro chips. It was getting a bit late now at gone 1. When we arrived at the Ivy dear Angie, my sophisticated lady was looking harassed. We begin paying attention only when someone is producing a remarkable performance. Genius followed by mediocrity is a story arc we all notice. Mediocrity followed by genius just looks like genius — assuming the mediocre performer gets a second chance. Not all do. So I wish Mr Woodford well.
Perhaps he has lost his touch, perhaps the world has changed, or perhaps he has simply been unlucky. It would be nice to know which, but in such matters the world does not always satisfy our curiosity. Written for and first published in the Financial Times on 24 May She had hoped to become a ballet dancer. After her leg was shattered in an accident at the age of 15, she took singing lessons instead. It was a striking detail in the obituaries.
If not for that painful setback, the star that was Doris Day would never have risen. Was the car accident that redirected her career an extraordinary twist in the story of an extraordinary life? Or was it typical of some broader truth about life, that frustrations can actually help us? Perhaps it is true that what does not kill us makes us stronger.
It may, in contrast, be that what does not kill us nevertheless slows us down. The conventional wisdom is that initial advantages tend to snowball into an avalanche of privilege. Being a few months older at the age of five means you are stronger and faster, are more likely to be picked for school teams, get more practice and are still reaping the benefits as an adult athlete. The effect is particularly well-studied among boys playing ice hockey in Canada, and football in a variety of countries. At other times, well-deserved acclaim is followed by unearned praise.
If three researchers collaborate on a problem, and one of them already has a Nobel Prize, the laureate tends to earn disproportionate recognition for the joint work. When a teacher and a student work together, the senior researcher is cited because that name is already recognised.
The junior is easily forgotten. In the wider workplace, we have evidence that the luck of graduating in a benign economic climate can lead to a lasting advantage. One researcher, Paul Oyer, found that young PhD and MBA students who started off in favourable job markets were employed in better places with smarter colleagues, and were still doing better a decade later than those who started out in tougher times. All this suggests that setbacks are setbacks: they drag us down, perhaps disproportionately. Doris Day was an exception, not the rule. Yet a striking new study suggests that the Doris Day effect is quite real in one particular group of people: young scientists applying for research grants.
In particular, they focused on borderline decisions, comparing those who scraped through to get a grant with those who just missed out. The near-winners and the near-losers were otherwise indistinguishable before the decision point, but afterwards it was the losers who prospered, publishing substantially more highly cited research papers.
We should remember that anyone in a position to nearly secure a million-dollar research grant has presumably enjoyed a few successes along the way at school and university. Still: this is a counterintuitive finding. Yet I was not entirely surprised to encounter it. It may be that many people respond to a setback by bouncing back with renewed determination. It may also be that the failure provokes a rethink and a fresh course of action. Doris Day, after all, did not respond to a shattered leg by trying even harder to become a dancer.
She changed her goals and prospered as a result. Something as mundane as a strike disrupting regular commuting has been shown to push people towards new habits. Often failure is simply failure, and a setback is exactly what it seems. But sometimes the obstacle that has been placed in our path might provoke us to look around, and perhaps to discover that a better route was there all along. Written for and first published in the Financial Times on 17 May Tension is rising in the Harford household as exams approach and we try to persuade Miss Harford Sr to relax, and Miss Harford Jr to be slightly less relaxed.
In a multiple-choice test, you sometimes write down an answer and then have second thoughts. Is it wise to stay with your first instincts, or better to switch? Most people would advise that the initial answer is usually better than the doubt-plagued second guess. Three-quarters of students think so, according to various surveys over the years. College instructors think so too, by a majority of 55 to 16 per cent. This confidence would be reassuring, were it not utterly erroneous. Researchers have been studying this question since the s. They have overwhelmingly concluded both that individual answer changes are more likely to be from wrong to right, and that students who change their answers tend to improve their scores.
No doubt our first instincts are often right, but when we start to have second thoughts, the second thoughts are usually occurring for a reason. It is better to switch. Justin Kruger, a psychologist at New York University, has been studying this question. Prof Kruger is more famous as co-discoverer of the Dunning-Kruger effect: people who are incompetent are too incompetent to realise how incompetent they are. With his colleagues Derrick Wirtz and Dale Miller he replicated the longstanding findings that college students believe you should trust your first answer in a multiple choice question, and yet that switching to a second answer tends to improve your grades.
Then the trio started to explore why. In the study, both strategies produced identical results, yet subjects watching a switching teammate were more frustrated and critical and had a good memory for the errors. Another study by Prof Kruger and his colleagues showed that we also have a warped recollection of our own errors in multiple choice tests. We have a rosy memory of sticking to our first instincts, forgetting the failures and exaggerating the successes. We vividly recall switching to the wrong answer and overestimate how often we did so. In short, we remember sticking as having been the best tactic, when in fact switching was better.
Our own experiences do indeed tell us that, but only because we misremember the lessons of previous switches.
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If you — or a loved one — are about to enter exam season, perhaps this evidence-based strategy will be of use. How often in life do we make a choice and then stick to it despite mounting doubts? In politics, such questions are aggravated by questions of partisanship and pride. Nobody wants to admit that they were wrong in the face of jeers from those on the opposite side of the political fence. The U-turn is one of the greatest sins in politics, if only because it is so easy to criticise.
Either you were wrong before or you are wrong now. But even in everyday life, we find ourselves clinging to bad choices. Steven Levitt, the co-author of Freakonomics , once conducted a study in which people hesitating over big choices — to leave a spouse, to adopt a child, to quit a job, to start a business — agreed to be guided by a coin toss.
Those who had been nudged to act ended up being happier several months on than those who had been nudged to stick with the status quo. We are prone to cling tightly to the devil we know. The likely explanation is that we are seeking to minimise regret. We starkly remember the times we changed things for the worse, and we more easily forget the times when we failed to change things for the better.
Instead, the lesson is that if you are hesitating over whether to leave things as they are, you probably needed to make a change some time ago. It is dimly remembered as a lament about the mutual incomprehension between arts and sciences, wrapped up with some pompous anecdotes about Oxbridge high table and airy generalisations about the dynamism of scientists. Some of it is absurd. Orwell old chap, relax and enjoy the fruits of technological progress!
Nevertheless, Snow was on to something important. His message was garbled, in fact, because he was on to several important things at once. The first is the challenge of collaboration. If anything, The Two Cultures understates that. Yes, the classicists need to work with the scientists, but the physicists also need to work with the biologists, the economists must work with the psychologists, and everyone has to work with the statisticians.
And the need for collaboration between technical experts has grown over time because, as science advances and problems grow more complex, we increasingly live in a world of specialists. The economist Benjamin Jones has been studying this issue by examining databases of patents and scientific papers. His data show that successful research now requires larger teams filled with more specialised researchers. Scientific and material progress demands complex collaboration. Snow appreciated — in a way that many of us still do not — how profound that progress was.
Had Gould checked the numbers , he would have seen that between and , the proportion of people living in extreme poverty had roughly halved, and it has continued to fall sharply since then.
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But the deepest point of all — buried a little too deep, perhaps — is a practical problem that remains as pressing today as it was in how to reconcile technical expertise with the demands of policy and politics. In short — have we really had enough of experts? There have never been many scientists in politics. The US Congress is packed with lawyers. We need a little more technical expertise close to the levers of power: pithy quotations from Cicero will not do the trick; nor those from Karl Marx. As Snow pointed out in a series of lectures he gave at Harvard in , published as Science and Government, grave mistakes can result not only from a vacuum of technical knowledge in politics, but from a monopoly — the single expert, unchallenged.
He cited the allied bombing of dense urban areas in Germany during the war, which not only took a terrible toll on civilians, but failed in military terms by sparing industrial targets. It is not enough to give political influence to a physicist or an economist. The corridors of power must ring with scientifically informed debate.
Snow quotes another scientist about losing the argument over area-bombing. There is no moral equivalence, but there is an intellectual parallel: we felt that a serious mistake had been made and that it was partly our fault for not being more persuasive. None of this is to assert the superiority of a technical education over a classical, literary or vocational one, although Snow sometimes seemed to yield to that temptation.
We need a mix. Like scientific research, good policymaking is now a team effort. It requires different perspectives and a range of specialist expertise.